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Cryogenic Processing Equipment

Related Companies

When it comes to thermal processing equipment, AFC-Holcroft has one of the most diversified product lines in the heat treat equipment industry. We are fully equipped to design, manufacture, ship, install, and service all types of custom and standard heat treat systems. We've been making high quality thermal processing equpiment since 1916. Find out why some of the best-known names in manufacturing trust AFC-Holcroft equipment for their production. ISO 9001:2008 certified.

All Metals & Forge Group, LLC
All Metals & Forge produces rings, flanges, gear blanks, single and double hubs, trunnions, bevel gear blanks, couplings, seamless rolled rings, rims, center hubs, sleeves, gear blanks, discs (pancake forgings), pinion shafts, step-downs, spindles, rack forgings in gear quality carbon and alloy steels with through-hardening, carburizing and bearing quality grades with forged-in steps to save on machining. Shafts are available up to 45-feet-long and 50,000 pounds and the company can produce part weights from under 100 pounds to more than 30 tons for the gear industry.

Applied Process
Applied Process is a world leader in austempering technology.

ECM Technologies started manufacturing heat-treatment furnaces in 1928. Since that time, ECM personnel have always been completely committed to extending their knowledge in the field of temperature control, high pressures, vacuum and the behavior of materials. This expertise, on an industrial scale, has always been enriched by our close partnership with furnace users, engineers, heat treat engineers and developers. Today, our knowledge base is at the core of all our customers' production lines. It is this concern for caring and listening, combined with our passion for our profession, which has forged ECM Technology and ECM USA’s recognized spirit of innovation.

Gear Resource Technologies Inc.
Gear Resource Technologies, Inc. (GRT) has focused directly upon precision tooling needs of gear manufacturers, since 1997. We provide a highly-responsive engineering, analytical, and manufacturing resource, for the many specific tooling needs of the industry.

Inductoheat Inc.
Inductoheat is the largest global manufacturer of induction heating equipment. We are part of the Inductotherm Group of some 40 companies worldwide. We design & build heat treating equipment & power supplies for heating a wide range of parts including gears & sprockets.

Involute Simulation Softwares Inc.
Involute Simulation Softwares specializes in the development of gear calculation and manufacturing software. The main product, HyGEARS™ V 4.0, offers gear designers and manufacturers a standalone software package providing all the design, analysis and manufacturing tools needed from idea to production.

Ipsen, Inc.
Ipsen, Inc. designs and manufactures thermal processing systems (vacuum heat treat furnaces and atmosphere heat treat furnaces) for a wide variety of markets, including Aerospace, Medical, Energy, Chemical and Automotive. With thousands of installed systems worldwide, whether it's innovative titanium knee implants, making cars more efficient, developing new jet engines or going to the moon, Ipsen delivers quality.

The KISSsoft calculation program has been developed to focus on the needs of mechanical engineers and power transmission profes

Liebherr America
Liebherr Gear Technology Co. is your North American access point to a broad range of technically advanced gear manufacturing technologies and processes.

McInnes Rolled Rings
McInnes Rolled Rings manufactures seamless rolled ring forgings from 4" - 144" OD. Offering quick quotes and fast, reliable deliveries. ISO9001 & AS9100 Certified.

Solar Atmospheres
Solar Atmospheres specializes in vacuum heat treating, vacuum nitriding, vacuum brazing as well as vacuum carburizing services. With processing expertise and personalized service, Solar will process your small or large parts efficiently with our unique range of 40 vacuum furnaces. Sizes range from lab furnaces to the world's largest commercial vacuum furnace.

Stresstech Oy
Stresstech provides products and services for process control and quality inspection of gears, camshafts,crankshafts, bearings, valves, etc. Applications for monitoring various manufacturing processes, such as grinding, super finishing, shot peening, heat treatment, case depth after case hardening, etc. Turnkey solutions, instruments and measurement services based on Barkhausen Noise (BN), X-ray Diffraction (XRD) and hole-drilling for studying residual stresses, retained austenite contents, grinding burns, heat treat defects, and hardness changes, welding stresses, etc. Applications for the automotive, machine and aerospace industries.

Bodycote Thermal Processing - Highland Heights
Bodycote Thermal Processing - Melrose Park
C & B Machinery
Controlled Thermal Processing, Inc.
Drake Manufacturing Services Co. Inc.
Drewco Workholding
Fässler by Daetwyler Industries
Flame Metals Processing Corporation
Ingersoll Cutting Tools
J. L. Becker Co.
Kleiss Gears, Inc.
Klingelnberg GmbH
Metallurgical Processing, Inc.
MPT Manufacturing Process Technologies
Precision Thermal Processing
Roto-Flo / U.S. Gear Tools
Sandvik Coromant
Seco/Warwick Corp.
Spectrum Thermal Processing
U.S. Gear Tools

Related Power Transmission Companies

Arrow Gear Co.
Since its inception in 1947, Arrow Gear Company has continued to build a solid reputation for quality, service and reliability. From the very beginning, Arrow has provided high precision spur, helical and bevel gears that meet the rapidly changing and the demanding requirements of many industries.

BRECOflex CO., L.L.C.
BRECOflex CO., L.L.C. ? The world leader in the polyurethane timing belt industry sets higher standards with new state-of-the-art products. BRECOflex timing belts, pulleys and accessories are scientifically designed and manufactured for undeviatin...

Circle Gear & Machine Co.
Quality Custom Gearing Complete Machine Shop ? Reverse Engineering ? Breakdown Service Available

Cone Drive
Cone Drive Gearing Solutions, based in Traverse City, Michigan, is an industry leader in motion control and industrial power transmission solutions. Cone Drive has extensive experience in many industries; including solar, metals, mining, defense, oil & gas, food packaging & process, pulp & paper, plastics, entertainment and more. Cone Drive is the world leader in double enveloping worm gear technology, which delivers solutions with the highest torque and shock load capacity in the smallest amount of space. Cone Drive's products are renowned for their durability and precision.

Gleason K2 Plastics
Gleason-K2 Plastics is in the business of plastic gear design and injection molding precision plastic components with a focus on precision plastic gears. Our lights-out automation enables production of the most cost effective, custom molded gears (spur gears, helical gears, bevel gears, planetary gears, internal gears), pulleys, bushings, rotary air motor rotors and vanes, along with plastic nozzle assemblies, at unmatched quality levels

IDC-USA is a cooperative partnering with independent distributors to improve the MRO solutions in their communities. Many IDC Distributors are 2nd and 3rd generation in their business and well respected in the industry. With more than 280 IDC Distributor locations across the United States, IDC Distributors help their customers stay up and running by providing the right product and expertise when they need it.

Lafert North America
Your best source for metric motors, gearboxes and coolant pumps, by providing quality products with the highest level of service in the industry.

Luoyang SBI Special Bearing Co. Ltd.
With highly advanced technology, Luoyang SBI Special Bearing Co., Ltd. has been dedicated to providing a wide variety of bearing solutions for industries all around the world since its establishment in 1989.

Mach III Clutch Inc.
Mach III Clutch designs and manufactures air and spring set industrial friction clutches and brakes, clutch-brakes, clutch couplings, clutch mechanisms and mechanical torque limiters (slip clutches). All products made in the USA.

New Power Electric (USA) LLC
Whatever your needs in variable speed applications, you can trust our 200/300/400/500 series PMDC motors. Designed and built under the highest quality process for general industrial needs, our products are there to provide reliable performance for a long time.

NSK Corporation
NSK is a global manufacturer of bearings and other motion & control products. It operates 51 manufacturing facilities worldwide and 12 global technology centers of excellence that draw from world-leading industry knowledge and manufacturing experience. NSK's dedication to engineering innovation results in state-of-the-art products designed to improve performance and extend service life. NSK's unique Asset Improvement Program helps customers improve productivity and efficiency to significantly reduce operating costs. The company’s industry and process-specific expertise and solutions are applied to identify and solve problems that are limiting productivity. This enables customers to achieve improved performance, enhanced competitiveness and increased profitability.

RJ Link International, Inc.
We design and manufacture custom gearboxes, provide precision machined components and perform contract machining services - including gear grinding.

Ronson Gears Pty. Ltd.
Established in 1954 Ronson Gears, is your English speaking and English thinking Asia-Pacific alternative for Precision Gears and Gear Assemblies. Doing business internationally for almost 60 years, Ronson Gears has garnered a reputation for quality, delivery and first-class customer service.

Smalley Steel Ring Company
Smalley Steel Ring Company manufactures Spirolox® Retaining Rings and Smalley Wave Springs. Spiral/Spirolox rings are interchangeable with stamped ring grooves; require no special tooling for removal. Wave springs reduce heights by 50%, with equal force/deflection as standard coil springs. Fit in tight radial/axial spaces. 10,000 stock parts, carbon/stainless steel. Specials from .200"- 120"; No-Tooling-Charges.

Taiwan Precision Gear Corp.
TPG is one professional factory who manufactures all kinds motors, gear box, PMDC motor, drive, clutch, brake, coupling, vibration motor, variable speed drive, disco, right angle worm gear, other power transmission parts.

Articles About process

1 An Innovative Way of Designing Gear Hobbing Processes (May 2012)

In today’s manufacturing environment, shorter and more efficient product development has become the norm. It is therefore important to consider every detail of the development process, with a particular emphasis on design. For green machining of gears, the most productive and important process is hobbing. In order to analyze process design for this paper, a manufacturing simulation was developed capable of calculating chip geometries and process forces based on different models. As an important tool for manufacturing technology engineers, an economic feasibility analysis is implemented as well. The aim of this paper is to show how an efficient process design—as well as an efficient process—can be designed.

2 Applying Process Control to Gear Manufacturing (March/April 1992)

A common goal of gear manufacturers is to produce gearing that is competitively priced, that meets all quality requirements with the minimum amount of cost in a timely manner, and that satisfies customers' expectations. In order to optimize this goal, the gear manufacturer must thoroughly understand each manufacturing process specified, the performance capability of that process, and the effect of that particular process as it relates to the quality of the manufactured gear. If the wrong series of processes has been selected or a specific selected process is not capable of producing a quality part, manufacturing costs are greatly increased.

3 Optimization of a Process Chain for Gear Shaft Manufacturing (March/April 2013)

The research presented here is part of an ongoing (six years to date) project of the Cluster of Excellence (CoE). CoE is a faculty-wide group of researchers from RWTH Aachen University in Aachen (North Rhine-Westphalia). This presentation is a result of the group’s examination of "integrative production technology for high-wage countries," in which a shaft for a dual-clutch gearbox is developed.

4 Comparative Load Capacity Evaluation of CBN-Finished Gears (May/June 1990)

Cubic boron nitride (CBN) finishing of carburized gearing has been shown to have certain economic and geometric advantages and, as a result, it has been applied to a wide variety of precision gears in many different applications. In critical applications such as aerospace drive systems, however, any new process must be carefully evaluated before it is used in a production application. Because of the advantages associated with this process, a test program was instituted to evaluate the load capacity of aerospace-quality gears finished by the CBN process as compared to geometrically identical gears finished by conventional grinding processes. This article presents a brief description of the CBN process, its advantages in an aerospace application, and the results of an extensive test program conducted by Boeing Helicopters (BH) aimed at an evaluation of the effects of this process on the scoring, surface durability, and bending fatigue properties of spur gears. In addition, the results of an x-ray diffraction study to determine the surface and subsurface residual stress distributions of both shot-peened and nonshot-peened CBN-ground gears as compared to similar conventionally ground gears are also presented.

5 Gear Hardness Technology (March/April 1992)

In a very general sense, increasing the hardness of a steel gear increases the strength of the gear. However, for each process there is a limit to its effectiveness. This article contains background information on each of the processes covered. In each section what is desired and what is achievable is discussed. Typical processes are presented along with comments on variables which affect the result. By reviewing the capabilities and processes, it is possible to determine the limits to each process.

6 Gear Shaving - Process Simulation Helps to Comprehend an Incomprehensible Process (September/October 2006)

Due to its economical efficiency, the gear shaving process is a widely used process for soft finishing of gears. A simulation technique allows optimization of the process.

7 Bevel Gear Manufacturing Troubleshooting (March/April 1991)

The quality of gearing is a function of many factors ranging from design, manufacturing processes, machine capability, gear steel material, the machine operator, and the quality control methods employed. This article discusses many of the bevel gear manufacturing problems encountered by gear manufacturers and some of the troubleshooting techniques used.

8 Practical Magic - Metrology Products Keep Pace with Machine Technology (July 2009)

Gear metrology is a revolving door of software packages and system upgrades. It has to be in order to keep up with the productivity and development processes of the machines on the manufacturing floor. Temperature compensation, faster inspection times and improved software packages are just a few of the advancements currently in play as companies prepare for new opportunities in areas like alternative energy, automotive and aerospace/defense.

9 Innovative Induction Hardening Process with Pre-heating for Improved Fatigue Performance of Gear Component (July 2014)

Contact fatigue and bending fatigue are two main failure modes of steel gears, while surface pitting and spalling are two common contact fatigue failures -- caused by alternating subsurface shear stresses from the contact load between two gear mates. And when a gear is in service under cyclic load, concentrated bending stresses exist at the root fillet -- the main driver of bending fatigue failures. Induction hardening is becoming an increasingly popular response to these problems, due to its process consistency, reduced energy consumption, clean environment and improved product quality -- but not without issues of its own (irregular residual stresses and bending fatigue). Thus a new approach is proposed here that flexibly controls the magnitude of residual stress in the regions of root fillet and tooth flank by pre-heating prior to induction hardening. Using an external spur gear made of AISI 4340 as an example, this new concept/process is demonstrated using finite element modeling and DANTE commercial software.

10 Optimum Shot Peening Specification - I (November/December 1991)

Shot peening is widely recognized as a prove, cost-effective process to enhance the fatigue characteristics of metal parts and eliminate the problems of stress corrosion cracking. Additional benefits accrue in the areas of forming and texturizing. Though shot peening is widely used today, the means of specifying process parameters and controlling documents for process control are not widely understood. Questions regarding shot size, intensity, and blueprint specification to assure a high quality and repeatable shot peening process are continually asked by many design and materials engineers. This article should answer many of the questions frequently asked by engineering professionals and to further assist companies interested in establishing a general shot peening specification.

11 18 Things You Should Know About SPC for Gears (November/December 1996)

Statistical Precess Control (SPC) and statistical methods in general are useful techniques for identifying and solving complex gear manufacturing consistency and performance problems. Complex problems are those that exist in spite of our best efforts and the application of state-of-the-art engineering knowledge.

12 Heat Treat 2013 (March/April 2013)

An overview of the latest technology and trends in heat treating.

13 User-Friendly Gear Measurement (July 2010)

Good timing leads to partnership between Process Equipment and Schafer Gear.

14 Industry News (July 2014)

The complete Industry News section from the July 2014 issue of Gear Technology.

15 Industry News (March/April 2013)

The complete Industry News section from the March/April 2013 issue of Gear Technology.

16 Dry Hobbing Proess Technology Road Map (March/April 2001)

Recent trends in gear cutting technology have left process engineers searching for direction about which combination of cutting tool material, coating, and process technology will afford the best quality at the lowest total cost. Applying the new technologies can have associated risks that may override the potential cost savings. The many interrelated variables to be considered and evaluated tend to cloud the issue and make hobbing process development more difficult.

17 Experimental Characterization of Bending Fatigue Strength in Gear Teeth (January/February 2003)

The effort described in this paper addresses a desire in the gear industry to increase power densities and reduce costs of geared transmissions. To achieve these objectives, new materials and manufacturing processes, utilized in the fabrication of gears, and being evaluated. In this effort, the first priority is to compare the performance of gears fabricated using current materials and processes. However, once that priority is satisfied, it rapidly transforms to requiring accurate design data to utilize these novel materials and processes. This paper describes the effort to address one aspect of this design data requirement.

18 The Submerged Induction Hardening of Gears (March/April 2001)

The tooth-by-tooth, submerged induction hardening process for gear tooth surface hardening has been successfully performed at David Brown for more than 30 years. That experience - backed up by in-depth research and development - has given David Brown engineers a much greater understanding of, and confidence in, the results obtainable from the process. Also, field experience and refinement of gear design and manufacturing procedures to accommodate the induction hardening process now ensure that gears so treated are of guaranteed quality.

19 Low Pressure Carburizing of Large Transmission Parts (September/October 2009)

Often, the required hardness qualities of parts manufactured from steel can only be obtained through suitable heat treatment. In transmission manufacturing, the case hardening process is commonly used to produce parts with a hard and wear-resistant surface and an adequate toughness in the core. A tremendous potential for rationalization, which is only partially used, becomes available if the treatment time of the case hardening process is reduced. Low pressure carburizing (LPC) offers a reduction of treatment time in comparison to conventional gas carburizing because of the high carbon mass flow inherent to the process (Ref. 1).

20 New Approaches to Nitriding (March/April 1997)

The process of nitriding has been used to case harden gears for years, but the science and technology of the process have not remained stagnant. New approaches have been developed which are definitely of interest to the gear designer. These include both new materials and new processing techniques.

21 Heat Treat Process and Material Selection for High Performance Gears (March/April 2003)

The selection of the heat treat process and the congruent material required for high performance gears can become very involved.

22 Gear Heat Treating in the 90s: Beyond Black Magic (March/April 1995)

Heat Treating - The evil twin of the gear processing family. Heat treating and post-heat treating corrective processes can run up to 50% or more of the total gear manufacturing cost, so it's easy to see why, in these days when "lean and mean" production is the rage, and every part of the manufacturing process is under intense scrutiny, some of the harshest light falls on heat treating.

23 Improved Ion Bond Recoating for the Gear Manufacturing Industry (January/February 1997)

This article summarizes the development of an improved titanium nitride (TiN) recoating process, which has, when compared to conventional recoat methods, demonstrated tool life increases of up to three times in performance testing of hobs and shaper cutters. This new coating process, called Super TiN, surpasses the performance of standard TiN recoating for machining gear components. Super TiN incorporates stripping, surface preparation, smooth coating techniques and polishing before and after recoating. The combination of these improvements to the recoating process is the key to its performance.

24 Powder Metallurgy Innovations (September/October 1999)

Powder metal. To gear makers today, the phrase conjures images of low power applications in non-critical systems. As powder metal technology advances, as the materials increase in density and strength, such opinions are changing. It is an ongoing, evolutionary process and one that will continue for some time. According to Donald G. White, the executive director of the Metal Powder Industries Federation, in his State-of-the-P/M Industry - 1999 report. "The P/M world is changing rapidly and P/M needs to be recognized as a world-class process - national, continental and even human barriers and prejudices must be eliminated - we must join forces as a world process - unified in approach and goals."

25 Ferritic Nitrocarburizing Gears to Increase Wear Resistance and Reduce Distortion (March/April 2000)

Quality gear manufacturing depends on controlled tolerances and geometry. As a result, ferritic nitrocarburizing has become the heat treat process of choice for many gear manufacturers. The primary reasons for this are: 1. The process is performed at low temperatures, i.e. less than critical. 2. the quench methods increase fatigue strength by up to 125% without distorting. Ferritic nitrocarburizing is used in place of carburizing with conventional and induction hardening. 3. It establishes gradient base hardnesses, i.e. eliminates eggshell on TiN, TiAIN, CrC, etc. In addition, the process can also be applied to hobs, broaches, drills, and other cutting tools.

26 Hob Tool Life Technology Update (March/April 2009)

The method of cutting teeth on a cylindrical gear by the hobbing process has been in existence since the late 1800s. Advances have been made over the years in both the machines and the cutting tools used in the process. This paper will examine hob tool life and the many variables that affect it. The paper will cover the state-of-the-art cutting tool materials and coatings, hob tool design characteristics, process speeds and feeds, hob shifting strategies, wear characteristics, etc. The paper will also discuss the use of a common denominator method for evaluating hob tool life in terms of meters (or inches) per hob tooth as an alternative to tool life expressed in parts per sharpening.

27 New Vacuum Processes (August 2007)

This paper introduces new process developments in low-pressure carburizing and carbonitriding using either high-pressure gas quenching or interrupted gas quenching.

28 Hard Gear Processing with Skiving Hobs (March/April 1985)

As we approach the problem of hard gear processing, it is well to take a look at the reason for discussing it at this time. In our present economic atmosphere throughout the world, more and more emphasis is being placed upon efficiency which is dictated by higher energy costs.

29 Hard Cutting - A Competitive Process in High Quality Gear Production (May/June 1987)

The higher load carrying capacities, compact dimensions and longer life of hardened gears is an accepted fact in industry today. However, the costs involved in case hardening and subsequent finishing operations to achieve these advantages are considerable. For example, in order to achieve desired running properties on larger gears, it has been necessary to grind the tooth flanks. This costly operation can now be replaced, in many cases, by a new Hard Cutting (HC) process which permits the cutting of hardened gears while maintaining extremely low tooling costs.

30 Optimization of the Gear Profile Grinding Process Utilizing an Analogy Process (November/December 2006)

In order to grind gears burn-free and as productively as possible, a better understanding of the process is required.

31 American Wera Profilator Introduces Scudding Process (January/February 2008)

Rolled out at EMO 2007, the Scudding process is a continuous cutting operation that uses a tool design similar to a helical shaper cutter. It can be used for a wide range of gear applications...

32 The Effects of Pre-Rough Machine Processing on Dimensional Distortion During Carburizing (September/October 2006)

A study was conducted to isolate the influence of pre-rough machine processing on final dimensional distortion.

33 Minimization of In-Process Corrosion of Aerospace Gears (July/August 2002)

Carbon steels have primarily been used to manufacture aerospace gears due to the steels' mechanical characteristics. An alloyed low carbon steel is easily case-hardened to obtain a hard wear surface while maintaining the ductile core characteristics. The microstructure achieved will accept the heavy loading, shocks, and elevated temperatures that gears typically experience in applications. The carbon steel machinability allows for general machining practices to be employed when producing aerospace gears versus the more advanced metal removal processes required by stainless and nickel-based alloys.

34 Cutting Fluid Selection and Process Controls for the Gear Manufacturing Industry (July/August 1987)

The last decade has been a period of far-reaching change for the metal working industry. The effect of higher lubricant costs, technical advances in machine design and increasing competition are making it essential that manufacturers of gears pay more attention to testing, selecting and controlling cutting fluid systems. Lubricant costs are not a large percentage of the process cost relative to items such as raw materials, equipment and labor, and this small relative cost has tended to reduce the economic incentive to evaluate and to change cutting fluids.

35 The Process of Gear Shaving (January/February 1986)

Gear shaving is a free-cutting gear finishing operation which removes small amounts of metal from the working surfaces of the gear teeth. Its purpose is to correct errors in index, helical angle, tooth profile and eccentricity. The process can also improve tooth surface finish and eliminate, by crowned tooth forms, the danger of tooth end load concentrations in service. Shaving provides for form modifications that reduce gear noise. These modifications can also increase the gear's load carrying capacity, its factor of safety and its service life.

36 The Frugal Certification Process (July/August 1994)

Much about ISO 9000 is the subject of noisy debate. But on one thing almost everyone, true believers and critics alike, agrees: Getting ISO 9000 certification can be expensive. Companies can expect to spend at least $35,000 for basic certification and six-month checkup fees over a three-year period. These figures do not include hidden costs like time and money spent on internal improvements required to meet ISO 9000 certification. But the really big-ticket items in the process are employee time and the cost of bringing in outside consultants. Many ISO 9000 consultants charge upwards of $1,800 a day.

37 The Gear Hobbing Process (January/February 1994)

Gear hobbing is a generating process. The term generating refers to the fact that the gear tooth form cut is not the conjugate form of the cutting tool, the hob. During hobbing both the hob and the workpiece rotate in a continuous rotational relationship. During this rotation, the hob is typically fed axially with all the teeth being gradually formed as the tool traverses the work face (see Fig. 1a).

38 Gear Blanking (May/June 1992)

The term "blanking" refers to the initial metal cutting operations in the process planning sequence which produce the contour of a part starting from rough material. The scope of blanking is: To remove the excess material To machine the part to print specifications, except for those surfaces with subsequent finishing operations. To leave adequate machining stock for finishing operations. To prepare good quality surfaces for location and clamping of the part throughout the process.

39 Dearborn Precision Puts Dual Purpose Zeiss CMM to the Task (May 2011)

When parts you manufacture pass through numerous processes such as deep hole drilling, machining, hobbing and grinding, a CMM is essential when your customers require 100 percent in-process and final inspection.

40 Using Hobs for Skiving; A Pre-Finish and Finishing Solution (May/June 1993)

Our company manufactures a range of hardened and ground gears. We are looking into using skiving as part of our finishing process on gears in the 4-12 module range made form 17 CrNiMO6 material and hardened to between 58 and 62 Rc. Can you tell us more about this process?

41 Dual Frequency Induction Gear Hardening (March/April 1993)

In the typical gear production facility, machining of gear teeth is followed by hear treatment to harden them. The hardening process often distorts the gear teeth, resulting in reduced and generally variable quality. Heat treating gears can involve many different types of operations, which all have the common purpose of producing a microstructure with certain optimum properties. Dual frequency induction hardening grew from the need to reduce cost while improving the accuracy (minimizing the distortion) of two selective hardening processes: single tooth induction and selective carburizing.

42 Low-Distortion Heat Treatment of Transmission Components (October 2011)

This paper presents how low pressure carburizing and high pressure gas quenching processes are successfully applied on internal ring gears for a six-speed automatic transmission. The specific challenge in the heat treat process was to reduce distortion in such a way that subsequent machining operations are entirely eliminated.

43 Design Guidelines for High-Capacity Bevel Gear Systems (January/February 1992)

The design of any gearing system is a difficult, multifaceted process. When the system includes bevel gearing, the process is further complicated by the complex nature of the bevel gears themselves. In most cases, the design is based on an evaluation of the ratio required for the gear set, the overall envelope geometry, and the calculation of bending and contact stresses for the gear set to determine its load capacity. There are, however, a great many other parameters which must be addressed if the resultant gear system is to be truly optimum. A considerable body of data related to the optimal design of bevel gears has been developed by the aerospace gear design community in general and by the helicopter community in particular. This article provides a summary of just a few design guidelines based on these data in an effort to provide some guidance in the design of bevel gearing so that maximum capacity may be obtained. The following factors, which may not normally be considered in the usual design practice, are presented and discussed in outline form: Integrated gear/shaft/bearing systems Effects of rim thickness on gear tooth stresses Resonant response

44 CBN Gear Grinding - A Way to Higher Load Capacity (November/December 1993)

Because of the better thermal conductivity of CBN abrasives compared to that of conventional aluminum oxide wheels, CBN grinding process, which induces residual compressive stresses into the component, and possibly improves the subsequent stress behavior. This thesis is the subject of much discussion. In particular, recent Japanese publications claim great advantages for the process with regard to an increased component load capacity, but do not provide further details regarding the technology, test procedures or components investigated. This situation needs clarification, and for the this reason the effect of the CBN grinding material on the wear behavior and tooth face load capacity of continuously generated ground gears was further investigated.

45 Simulation of Deviations in Hobbing and Generation Grinding (September/October 2014)

The hobbing and generation grinding production processes are complex due to tool geometry and kinematics. Expert knowledge and extensive testing are required for a clear attribution of cause to work piece deviations. A newly developed software tool now makes it possible to simulate the cutting procedure of the tool and superimpose systematic deviations on it. The performance of the simulation software is illustrated here with practical examples. The new simulation tool allows the user to accurately predict the effect of errors. With this knowledge, the user can design and operate optimal, robust gearing processes.

46 Improved Gear Life Through Controlled Shot Peening (September/October 1986)

The search for greater gear life involves improvement in cost, weight and increased power output. There are many events that affect gear life, and this paper addresses those relating to fatigue, gear tooth pitting, fatigue strength losses due to the heat treating processes and shot peening technique. The capability of shot peening to increase fatigue strength and surface fatigue life eliminate machine marks which cause stress risers, and to aid in lubrication when properly controlled, suggests increased use and acceptance of the process.

47 Manufacturing of Forged and Extruded Gears (July/August 1990)

Traditional methods of manufacturing precision gears usually employ either hobbing or shaper cutting. Both of these processes rely upon generating the conjugate tooth form by moving the work-piece in a precise relation to the tool. Recently, attention has been given to forming gear teeth in a single step. Advantages to such a process include reduced production time, material savings, and improved performance characteristics. Drawbacks include complicated tool designs, non-uniformity of gears produced throughout the life of the tooling, and lengthy development times.

48 Controlling Gear Distortion and Residual Stresses During Induction Hardening (March/April 2012)

Induction hardening is widely used in both the automotive and aerospace gear industries to minimize heat treat distortion and obtain favorable compressive residual stresses for improved fatigue performance. The heating process during induction hardening has a significant effect on the quality of the heat-treated parts. However, the quenching process often receives less attention even though it is equally important.

49 Fundamentals of Bevel Gear Hard Cutting (November/December 1990)

Some years back, most spiral bevel gear sets were produced as cut, case hardened, and lapped. The case hardening process most frequently used was and is case carburizing. Many large gears were flame hardened, nitrided, or through hardened (hardness around 300 BHN) using medium carbon alloy steels, such as 4140, to avoid higher distortions related to the carburizing and hardening process.

50 Shaper Cutters-Design & Applications Part 1 (March/April 1990)

Gear shaping is one of the most popular production choices in gear manufacturing. While the gear shaping process is really the most versatile of all the gear manufacturing methods and can cut a wide variety of gears, certain types of gears can only be cut by this process. These are gears closely adjacent to shoulders; gears adjacent to other gears, such as on countershafts; internal gears, either open or blind ended; crown or face gears; herringbone gears of the solid configuration of with a small center groove; rack; parts with filled-in spaces or teeth, such as are used in some clutches.

51 Mechanical Behavior and Microstructure of Ausrolled Surfaces in Gear Steels (March/April 1995)

Ausforming, the plastic deformation of heat treatment steels in their metastable, austentic condition, was shown several decades ago to lead to quenched and tempered steels that were harder, tougher and more durable under fatigue-type loading than conventionally heat-treated steels. To circumvent the large forces required to ausform entire components such as gears, cams and bearings, the ausforming process imparts added mechanical strength and durability only to those contact surfaces that are critically loaded. The ausrolling process, as utilized for finishing the loaded surfaces of machine elements, imparts high quality surface texture and geometry control. The near-net-shape geometry and surface topography of the machine elements must be controlled to be compatible with the network dimensional finish and the rolling die design requirements (Ref. 1).

52 New Developments in Gear Hobbing (March/April 2010)

Several innovations have been introduced to the gear manufacturing industry in recent years. In the case of gear hobbing—the dry cutting technology and the ability to do it with powder-metallurgical HSS—might be two of the most impressive ones. And the technology is still moving forward. The aim of this article is to present recent developments in the field of gear hobbing in conjunction with the latest improvements regarding tool materials, process technology and process integration.

53 The XL Gears Project (January/February 2014)

Much of the existing guidelines for making large, high-performance gears for wind turbine gearboxes exhibit a need for improvement. Consider: the large grinding stock used to compensate for heat treatment distortion can significantly reduce manufacturing productivity; and, materials and manufacturing processes are two other promising avenues to improvement. The work presented here investigates quenchable alloy steels that, combined with specifically developed Case-hardening and heat treatment processes, exhibits reduced distortion and, in turn, requires a smaller grinding stock.

54 Cutting Tools Roundup (May/June 1999)

The cutting tool industry has undergone some serious changes in the last couple of years in both technology and the way the industry does business. The emerging technology today, as well as for the foreseeable future, is dry cutting, especially in high volume production settings. Wet cutting continues to be as popular as ever with lubrication advances making it more economical and environmentally friendly. There has also developed a process called "near dry cutting." this process offers many of the benefits of fluids while eliminating many of hte associated problems.

55 Net-Shape Forged Gears - The State of the Art (January/February 2002)

Traditionally, high-quality gears are cut to shape from forged blanks. Great accuracy can be obtained through shaving and grinding of tooth forms, enhancing the power capacity, life and quietness of geared power transmissions. In the 1950s, a process was developed for forging gears with teeth that requires little or no metal to be removed to achieve final geometry. The initial process development was undertaken in Germany for the manufacture of bevel gears for automobile differentials and was stimulated by the lack of available gear cutting equipment at that time. Later attention has turned to the forging of spur and helical gears, which are more difficult to form due to the radial disposition of their teeth compared with bevel gears. The main driver of these developments, in common with most component manufacturing, is cost. Forming gears rather than cutting them results in increased yield from raw material and also can increase productivity. Forging gears is therefore of greater advantage for large batch quantities, such as required by the automotive industry.

56 Cleaner, More Energy Efficient: Trends in the Heat Treat Industry (March/April 2002)

an advancing technology and higher energy costs appear to be leading heat-treating companies in the gear industry toward cleaner, more energy-efficient processes. These processes may offer some relief to heat treaters through cooler factories and some relief to their companies through reduced energy usage.

57 Spiral Bevel Gear Development: Elminiating Trial and Erroe with Computer Technology (January/February 2003)

Computer technology has touched all areas of our lives, impacting how we obtain airline tickets, purchase merchandise and receive medical advice. This transformation has had a vast influence on manufacturing as well, providing process improvements that lead to higher quality and lower costs. However, in the case of the gear industry, the critical process of tooth contact pattern development for spiral bevel gears remains relatively unchanged.

58 Predicting the Heat-Treat Response of a Carburized Helical Gear (November/December 2002)

Using the DANTE software, a finite element simulation was developed and executed to study the response of a carburized 5120 steel helical gear to quenching in molten salt. The computer simulation included heat-up, carburization, transfer and immersion in a molten salt bath, quenching, and air cooling. The results of the simulation included carbon distribution of phases, dimensional change, hardness, and residual stress throughout the process. The predicted results were compared against measured results for hardness, dimensions and residual stress. The excellent agreement between predictions and measured values for this carburized 5120 steel gear provides a basis for assessing the various process parameters and their respective importance in the characteristics of not only these heat-treated parts, but of other compositions and shapes.

59 An Experimental Study on the Effect of Power Honing on Gear Surface Topography (January/February 1999)

Gear noise associated with tooth surface topography is a fundamental problem in many applications. Operations such as shaving, gear grinding and gear honing are usually used to finish the gear surface. Often, gears have to be treated by a combination of these operations, e.g. grinding and honing. This is because gear honing operations do not remove enough stock although they do create a surface lay favorable for quiet operation. See Fig. 1 for typical honing process characteristics. Gear grinding processes, on the other hand, do remove stock efficiently but create a noisy surface lay.

60 Automated Inspection Systems: The Whole Picture (January/February 1998)

No one (not even you and I) consistently makes parts with perfect form and dimensions, so we must be able to efficiently check size and shape at many stages in the manufacturing and assembly process to eliminate scrap and rework and improve processes and profits. Automated inspection systems, which are widely used in all kinds of manufacturing operations, provide great efficiencies in checking individual features, but may not be as effective when asked to evaluate an entire part. You need to know why this is true and what you can do to improve your part yields.

61 Gear Hobbing Without Coolant (November/December 1994)

For environmental and economic reasons, the use of coolant in machining processes is increasingly being questioned. Rising coolant prices and disposal costs, as well as strains on workers and the environment, have fueled the debate. The use of coolant has given rise to a highly technical system for handling coolant in the machine (cooling, filtering) and protecting the environment (filter, oil-mist collector). In this area the latest cutting materials - used with or without coolant - have great potential for making the metal-removal process more economical. The natural progression to completely dry machining has decisive advantages for hobbing.

62 The Fundamentals of Gear Press Quenching (March/April 1994)

Most steel gear applications require appreciable loads to be applied that will result in high bending and compressive stresses. For the material (steel) to meet these performance criteria, the gear must be heat treated. Associated with this thermal processing is distortion. To control the distortion and achieve repeatable dimensional tolerances, the gear will be constrained during the quenching cycle of the heat treatment process. This type of fixture quenching is the function of gear quench pressing equipment.

63 Avoiding Interference In Shaper-Cut Gears (January/February 1996)

In the process of developing gear trains, it occasionally occurs that the tip of one gear will drag in the fillet of the mating gear. The first reaction may be to assume that the outside diameter of the gear is too large. This article is intended to show that although the gear dimensions follow AGMA guidelines, if the gear is cut with a shaper, the cutting process may not provide sufficient relief in the fillet area and be the cause of the interference.

64 Gear Noise As a Result of Nicks, Burrs and Scale - What Can Be Done (July/August 1996)

There are many different causes of gear noise, all of them theoretically preventable. Unfortunately, the prevention methods can be costly, both in equipment and manpower. If the design of the gear and its application are appropriate, in theory all that is necessary is to have a tight control on the process of producing the finished gear. In reality, there are many variables that can cause a process, no matter how well-controlled, to deteriorate, and thus cause errors, some of which will cause a gear to produce unwanted noise when put to use.

65 Induction Heat Trating: Things Remembered, Things Forgotten (March/April 1997)

Many potential problems are not apparent when using new induction heat treating systems. The operator has been trained properly, and setup parameters are already developed. Everything is fresh in one's mind. But as the equipment ages, personnel changes or new parts are required to be processed on the old equipment ages, personnel changes or new parts are required to b processed on the old equipment, important information can get lost in the shuffle.

66 PPD Wear Protection Treatment for Large Parts Opens New Horizons (March/April 2014)

Environmentally friendly, highly efficient and lasting a product's lifetime. With characteristics like this, Pulsed-Plasma Diffusion (PPD) technology from Oerlikon Balzers has established itself as an industry standard for the treatment of large automotive press tooling. Now the technology specialists are targeting new applications with this advanced process, offering an alternative to traditional hard-chrome processes.

67 What is ISO 9000 and Why Should I Care (March/April 1994)

What follows is the first of three articles we will be running on ISO 9000 and what it means for the gear industry. This first article will cover what ISO 9000 is, what some of its benefits - and problems - are, and whether your company should be a candidate for this certification process. In our next issue, we will consider the important question of how, when, and if to hire an ISO 9000 consultant. The final article in this series will discuss ways to save money while streamlining the certification process in your company.

68 Gear Noise and the Making of Silent Gears (March/April 1990)

Our research group has been engaged in the study of gear noise for some nine years and has succeeded in cutting the noise from an average level to some 81-83 dB to 76-78 dB by both experimental and theoretical research. Experimental research centered on the investigation into the relation between the gear error and noise. Theoretical research centered on the geometry and kinematics of the meshing process of gears with geometric error. A phenomenon called "out-of-bound meshing of gears" was discovered and mathematically proven, and an in-depth analysis of the change-over process from the meshing of one pair of teeth to the next is followed, which leads to the conclusion we are using to solve the gear noise problem. The authors also suggest some optimized profiles to ensure silent transmission, and a new definition of profile error is suggested.

69 Software-Based Process Design in Gear Finish Hobbing (May 2010)

In this paper, the potential for geometrical cutting simulations—via penetration calculation to analyze and predict tool wear as well as to prolong tool life—is shown by means of gear finish hobbing. Typical profile angle deviations that occur with increasing tool wear are discussed. Finally, an approach is presented here to attain improved profile accuracy over the whole tool life of the finishing hob.

70 The Process of Gear Shaving (May/June 1984)

Gear shaving is a free-cutting gear finishing operation which removes small amounts of metal from the working surfaces of the gear teeth. Its purpose is to correct errors in index, helical angle, tooth profile and eccentricity.

71 Hobbing Precise, Uniform End Chamfers (March/April 2004)

The seemingly simple process of placing a uniform chamfer on the face ends of spur and helical gears, at least for the aerospace industry, has never been a satisfactory or cost effective process.

72 Low Pressure Carburizing with High Pressure Gas Quenching (March/April 2004)

High demands for cost-effectiveness and improved product quality can be achieved via a new low pressure carburizing process with high pressure gas quenching. Up to 50% of the heat treatment time can be saved. Furthermore, the distortion of the gear parts could be reduced because of gas quenching, and grinding costs could be saved. This article gives an overview of the principles of the process technology and the required furnace technology. Also, some examples of practical applications are presented.

73 Influence of Coatings and Surface Improvements on the Lifetime of Gears (July/August 2004)

Surface coatings or finishing processes are the future technologies for improving the load carrying capacity of case hardened gears. With the help of basic tests, the influence of different coatings and finishing processes on efficiency and resistance to wear, scuffing, micropitting, and macropitting is examined.

74 Gear Corrosion During the Manufacturing Process (September/October 2009)

No matter how well gears are designed and manufactured, gear corrosion can occur that may easily result in catastrophic failure. Since corrosion is a sporadic and rare event and often difficult to observe in the root fillet region or in finely pitched gears with normal visual inspection, it may easily go undetected. This paper presents the results of an incident that occurred in a gear manufacturing facility several years ago that resulted in pitting corrosion and intergranular attack (IGA).

75 Repair via Isotropic Superfinishing of Aircraft Transmission Gears (May 2009)

The objective of this paper is to demonstrate that transmission gears of rotary-wing aircraft, which are typically scrapped due to minor foreign object damage (FOD) and grey staining, can be repaired and re-used with signifi cant cost avoidance. The isotropic superfinishing (ISF) process is used to repair the gear by removing surface damage. It has been demonstrated in this project that this surface damage can be removed while maintaining OEM specifications on gear size, geometry and metallurgy. Further, scrap CH-46 mix box spur pinions, repaired by the ISF process, were subjected to gear tooth strength and durability testing, and their performance compared with or exceeded that of new spur pinions procured from an approved Navy vendor. This clearly demonstrates the feasibility of the repair and re-use of precision transmission gears.

76 Kinematical Simulation of Face Hobbing Indexing and Tooth Surface Generation of Spiral Bevel and Hypoid Gears (January/February 2006)

In addition to the face milling system, the face hobbing process has been developed and widely employed by the gear industry. However, the mechanism of the face hobbing process is not well known.

77 Issues of Gear Design Using 3D Solid Modeling Systems (January/February 1999)

More and more gear shops are wrestling with the issue of whether or not solid modeling is right for their gear design work. The Q & A Page of The Gear Industry Home Page has had numerous questions asking how to model gears in solid modeling applications such as AutoCAD, Solidworks and Pr/Engineer. Given the problems people have been having, we are presenting the step-by-step process for modeling gears in Pr/Engineer, but first we thought it would be a good idea to explore the question of whether or not you should even try to design gears using Pro/Engineer or any other 3D solid modeling program.

78 Dry Cutting of Bevel and Hypoid Gears (May/June 1998)

High-speed machining using carbide has been used for some decades for milling and turning operations. The intermittent character of the gear cutting process has delayed the use of carbide tools in gear manufacturing. Carbide was found at first to be too brittle for interrupted cutting actions. In the meantime, however, a number of different carbide grades were developed. The first successful studies in carbide hobbing of cylindrical gears were completed during the mid-80s, but still did not lead to a breakthrough in the use of carbide cutting tools for gear production. Since the carbide was quite expensive and the tool life was too short, a TiN-coated, high-speed steel hob was more economical than an uncoated carbide hob.

79 Choosing the Right Heat Treater (March/April 1998)

Heat treating is a critical operation in gear manufacturing. It can make or break the quality of your final product. Yet it is one that frequently gear manufacturers outsource to someone else. Then the crucial question becomes, how do you know you're getting the right heat treater? How can you guarantee your end product when you have turned over this important process to someone else?

80 Gear Failure Analysis Involving Grinding Burn (January/February 2009)

When gears are case-hardened, it is known that some growth and redistribution of stresses that result in geometric distortion will occur. Aerospace gears require post case-hardening grinding of the gear teeth to achieve necessary accuracy. Tempering of the case-hardened surface, commonly known as grinding burn, occurs in the manufacturing process when control of the heat generation at the surface is lost.

81 Production Increase When Hobbing with Carbide Hobs (January/February 1998)

We are all looking for ways to increase production without sacrificing quality. One of the most cost-effective ways is by improving the substrate material of your hob. Solid carbide hobs are widely used in many applications throughout the world. LMT-Fette was the first to demonstrate the use of solid carbide hobs in 1993 on modern high-speed carbide (HSC) hobbing machines. Since then the process of dry hobbing has been continuously improving through research and product testing. Dry hobbing is proving to be successful in the gear cutting industry as sales for dry hobbing machines have steadily been rising along with the dramatic increase in sales of solid carbide hobs.

82 Bigger and Better Than Ever (July/August 1999)

Gear Expo 99, AGMA's biennial showcase for the gear industry, has left the Rust Belt this year and landed in Music City U.S.A., Nashville, Tennessee. The event, with exhibitors from around the globe showing off the latest in gear manufacturing as well as metal working processes, will be held at the Nashville Convention Center, October 24-27, 1999. According to Kurt Medert, AGMA vice president and Gear Expo show manager, "In choosing Nashville, AGMA;s Trade Show Advisory Council found a city that is an excellent trade show site. It has the right mix of convention center, nearby hotels, and a clean downtown area with entertainment readily available for the exhibitors and visitors alike. Nashville is in the heart of southern industry, which we see as a focus of growth for the gear industry and its customers."

83 Hard Gear Finishing with a Geometrically Defined Cutting Edge (November/December 1999)

The market demand for gear manufacturers to transmit higher torques via smaller-sized gear units inevitably leads to the use of case-hardened gears with high manufacturing and surface quality. In order to generate high part quality, there is an increasing trend towards the elimination of the process-induced distortion that occurs during heat treatment by means of subsequent hard finishing.

84 Reducing Production Costs in Cylindrical Gear Hobbing and Shaping (March/April 2000)

Increased productivity in roughing operations for gear cutting depends mainly on lower production costs in the hobbing process. In addition, certain gears can be manufactured by shaping, which also needs to be taken into account in the search for a more cost-effective form of production.

85 Thermal Effects on CMMs (September/October 1997)

The trend toward moving coordinate measuring machines to the shop floor to become an integral part of the manufacturing operations brings real time process control within the reach of many companies. Putting measuring machines on the shop floor, however, subjects them to harsh environmental conditions. Like any measuring system, CMMs are sensitive to any ambient condition that deviates from the "perfect" conditions of the metrology lab.

86 The Gear Industry's Information Source (September/October 2004)

Since our founding in 1984, Gear Technology’s goal has been to educate and inform our readers of the technologies, products, processes, services and news of importance to the gear industry and to provide our advertisers with the most complete and current circulation of gear industry professionals available anywhere!

87 Fatigue Aspects of Case Hardened Gears (March/April 1999)

The efficient and reliable transmission of mechanical power continues, as always, to be a central area of concern and study in mechanical engineering. The transmission of power involves the interaction of forces which are transmitted by specially developed components. These components must, in turn, withstand the complex and powerful stresses developed by the forces involved. Gear teeth transmit loads through a complex process of positive sliding, rolling and negative sliding of the contacting surfaces. This contact is responsible for both the development of bending stresses at the root of the gear teeth and the contact stresses a the contacting flanks.

88 A New Approach to Heat Treating Parts Washing (March/April 1999)

New innovations in the management of hear treating parts washers and yielding powerful, unexpected benefits. Simply, cost effective shop floor practices are being combined in new ways to deliver big quality improvements and significant help to the bottom line. Employing these steps early in the process can dramatically cut waste hauling expenses and greatly reduce environmental liabilities while continuously producing cleaner parts.

89 Tooth Forms for Hobs (March/April 1985)

The gear hobbing process is a generating type of production operation. For this reason, the form of the hob tooth is always different from the form of the tooth that it produces.

90 Standard Issues (November/December 1996)

Standards are unlike gears themselves: mundane, but complex, ubiquitous and absolutely vital. Standards are a lingua franca, providing a common language with reference points for evaluating product reliability and performance for manufacturers and users. The standards development process provides a scientific forum for discussion of product design, materials and applications, which can lead to product improvement. Standards can also be a powerful marketing tool for either penetrating new markets or protecting established ones.

91 Chamfering and Deburring External Parallel Axis Gears (November/December 1996)

The chamfering and deburring operations on gear teeth have become more important as the automation of gear manufacturing lines in the automotive industry have steadily increased. Quieter gears require more accurate chamfers. This operation also translates into significant coast savings by avoiding costly rework operations. This article discusses the different types of chamfers on gear teeth and outlines manufacturing methods and guidelines to determine chamfer sizes and angles for the product and process engineer.

92 Powder Metal Gear Design and Inspection (September/October 1996)

Powder metallurgy (P/M) is a precision metal forming technology for the manufacture of parts to net or near-net shape, and it is particularly well-suited to the production of gears. Spur, bevel and helical gears all may be made by made by powder metallurgy processing.

93 Gear Wear Caused By Contaminated Oils (September/October 1996)

The diagnosis and prevention of gear tooth and bearing wear requires the discovery and understanding of the particular mechanism of wear, which in turn indicates the best method of prevention. Because a gearbox is a tribologically dependent mechanism, some understanding of gear and bearing tribology is essential for this process. Tribology is the general term for the study and practice of lubrication, friction and wear. If tribology is neglected or considered insignificant, poor reliability and short life will result.

94 Heat Treating Challenges for the Future (March/April 1996)

The heat treating of gears presents a difficult challenge to both the heat treater and the gear manufacturer. The number and variety of variables involved in the manufacturing process itself and the subsequent heat treating cycle create a complex matrix of factors which need to be controlled in order to produce a quality product. A heat treater specializing in gears or a gear manufacturer doing his own heat treating must have a clear understanding of these issues in order to deliver a quality product and make a profit at the same time. The situation also presents a number of areas that could benefit greatly from continued research and development.

95 EDM Specialty Gears (May/June 1996)

The capabilities and limitations of manufacturing gears by conventional means are well-known and thoroughly documented. In the search to enhance or otherwise improve the gear-making process, manufacturing methods have extended beyond chip-cutting - hobbing, broaching, shaping, shaving, grinding, etc. and their inherent limitations based on cutting selection and speed, feed rates, chip thickness per tooth, cutting pressure, cutter deflection, chatter, surface finish, material hardness, machine rigidity, tooling, setup and other items.

96 Austempered Nodular Cast Irons (March/April 1985)

Austempering heat treatments (austenitizing followed by rapid cooling to the tempering temperature) have been applied to nodular irons on an experimental basis for a number of years, but commercial interest in the process has only recently come to the surface.

97 Gear Software You Didn't Know About (January/February 1997)

Designing and manufacturing gears requires the skills of a mathematician, the knowledge of an engineer and the experience of a precision machinist. For good measure, you might even include the are of a magician, because the formulas and calculations involved in gear manufacturing are so obscure and the processes so little known that only members of an elite cadre of professionals can perform them.

98 Microsecond Heat Treatment of Gears (March/April 2000)

The performance of metal surfaces can be dramatically enhanced by the thermal process of rapid surface melting and re-solidification (RMRS). When the surface of a metal part (for instance, a gear) is melted and re-solidified in less than one thousandth of a second, the resulting changes in the material can lead to: Increased wear and corrosion resistance, Improved surface finish and appearance, Enhanced surface uniformity and purity, and Sealing of surface cracks and pores.

99 Detroit in 97 - the Biggest Gear Expo Ever (July/August 1997)

"A Decade of Performance" is the theme of the American Gear Manufacturers Association Gear Expo 97, to be held October 19-22 at Detroit's Cobo Hall. Products and services related to every aspect of the gear manufacturing process, from turning and grinding the blanks to coating and inspection of the gears,will be represented at the show.

100 The Broaching of Gears (March/April 1997)

Broaching is a process in which a cutting tool passes over or through a part piece to produce a desired form. A broach removes part material with a series of teeth, each one removing a specified amount of stock.

101 Inreasing Hardness Through Cryogenics (March/April 1997)

The Instrumented Factory for Gears (INFAC) conducted a metallurgical experiment that examined the effects of carburizing process variables and types of cryogenic treatments in modifying the microstructure of the material. The initial experiment was designed so that, following the carburizing cycles, the same test coupons could be used in future experiment.

102 Composite Electroless Nickel Coatings for the Gear Industry (January/February 1997)

Electroless Nickel (EN) plating, a process dating back to the 1940s, is one of the predominant metal finishing methods today. It is especially suitable for the gear industry, whose end uses span innumerable other industries, providing an endless assortment of requirements, environments, materials and specifications. EN plating has a broad array of functional features, which include:

103 Comparison of PM-HSS and Cemented Carbide Tools in High-Speed Gear Hobbing (September/October 2009)

This article examines the dry hobbing capabilities of two cutting tool materials—powder metallurgical high-speed steel (PM-HSS) and cemented carbide. Cutting trials were carried out to analyze applicable cutting parameters and possible tool lives as well as the process reliability. To consider the influences of the machinability of different workpiece materials, a case hardening steel and a tempered steel were examined.

104 Basic Honing & Advanced Free-Form Honing (July/August 1997)

Rotary gear honing is a crossed-axis, fine, hard finishing process that uses pressure and abrasive honing tools to remove material along the tooth flanks in order to improve the surface finish (.1-.3 um or 4-12u"Ra), to remove nicks and burrs and to change or correct the tooth geometry. Ultimately, the end results are quieter, stronger and longer lasting gears.

105 Austempered Gears and Shafts: Tough Solutions (March/April 2001)

Aurstempered irons and steels offer the design engineer alternatives to conventional material/process combinations. Depending on the material and the application, austempering may provide the producers of gear and shafts with the following benefits: ease of manufacturing, increased bending and/or contact fatigue strength, better wear resistance or enhanced dampening characteristics resulting in lower noise. Austempered materials have been used to improve the performance of gears and shafts in many applications in a wide range of industries.

106 How Gear Hobbing Works (March/April 2013)

Hobbing is one of the most fundamental processes in gear manufacturing. Its productivity and versatility make hobbing the gear manufacturing method of choice for a majority of spur and helical gears.

107 Reinventing Cutting Tool Production at Gleason (May 2013)

Investment in advanced new manufacturing technologies is helping to reinvent production processes for bevel gear cutters and coarse-pitch hobs at Gleason - delivering significant benefits downstream to customers seeking shorter deliveries, longer tool life and better results.

108 Light Weight Assembled Gears - A Green Design Solution (May 2013)

It is widely recognized that the reduction of CO2 requires consistent light-weight design of the entire vehicle. Likewise, the trend towards electric cars requires light-weight design to compensate for the additional weight of battery systems. The need for weight reduction is also present regarding vehicle transmissions. Besides the design of the gearbox housing, rotating masses such as gear wheels and shafts have a significant impact on fuel consumption. The current technology shows little potential of gear weight reduction due to the trade-off between mass optimization and the manufacturing process. Gears are usually forged followed or not by teeth cutting operation.

109 How to Conduct a Heat Treat Audit (March/April 2013)

Audits of the heat treating department are a vital part of any good quality program - either as part of a self-assessment or ISO program for a captive shop or - of equal importance - as part of an evaluation of the capabilities of a commercial heat treat supplier. In either case, the audit process needs to be formal in nature and follow specific guidelines.

110 DFM Crucial for Gear Industry Success (March/April 2013)

"Design for manufacturability" (DFM) is a well-established practice, essential to realizing the successful transformation of concepts into mass-produced gears and motion control devices. And yet, all too often issues that could have been avoided are identified very late in the process that impact production costs and schedules. This suggests that key DFM principles are often underutilized in practice and are not applied consistently - or to the degree necessary - to avoid these negative results.

111 Romax Technology Launches Gearbox and Driveline Design Software Package (November/December 2012)

Romax Technology, the gearbox, bearing and driveline engineering specialist, has launched a new design software package that will increase speed, quality, creativity and innovation when designing gearboxes and drivelines. Called Concept, the new product delivers on the Romax vision of streamlining the end-to-end, planning-to-manufacture process with open, easy to use software solutions. It has been developed in close collaboration with engineers in the largest ground vehicle, wind energy and industrial equipment companies around the globe.

112 Gear Shaving Basics - Part I (November/December 1997)

Gear shaving is a free-cutting gear finishing operation which removes small amounts of metal from the working surfaces of gear teeth. Its purpose is to correct errors in index, helix angle, tooth profile and eccentricity. The process also improves tooth surface finish and eliminates by means of crowned tooth forms the danger of tooth end load concentrations in service.

113 Design of a Flexible and Lean Machining Cell, Part I (June/July 2013)

Although a cell is dedicated to produce a single part family, it must have the requisite equipment capabilities, routing flexibility, cross-trained employees and, to the extent possible, minimal external process dependencies. Cells are often implemented in job shops since they provide the operational benefits of flowline production.

114 How Gear Standards are Written (September 2013)

The new chairman of the AGMA Technical Division Executive Committee explains what's involved in the process of developing technical standards at the AGMA.

115 Cracking the WIP (September/October 2014)

Over the past few months I've talked with several different gear manufacturers who are in the process of upgrading their gear making equipment with modern CNC machine tools. Each of these manufacturers has come to the realization that in order to stay competitive, he needs to streamline operations and become more efficient...

116 Getting the Right Tools (September/October 2014)

So there is little chance that they need the same software to assist with their work. Gone are the days when companies wrote their own code and process engineers thumbed the same tattered reference book.

117 Honing of Gears (August 2014)

The honing of gears - by definition - facilitates ease of operation, low noise and smoother performance in a transmission. Honing also contributes to reduced friction in the powertrain. Both the intense cutting (roughing process) as well as the functionally fine- finishing of transmission gears can be performed in one setup, on one machine.

118 New ECM Furnace Improves Manufacture Efficiency of PM Components (March/April 2014)

The heat treatment processing of powder metal (PM) materials like Astaloy requires four steps -- de-waxing, HT sintering, carburizing and surface hardening -- which are usually achieved in dedicated, atmospheric furnaces for sintering and heat treat, respectively, leading to intermediate handling operations and repeated heating and cooling cycles. This paper presents the concept of the multi-purpose batch vacuum furnace, one that is able to realize all of these steps in one unique cycle. The multiple benefits brought by this technology are summarized here, the main goal being to use this technology to manufacture high-load transmission gears in PM materials.

119 Power Skiving of Cylindrical Gears on Different Machine Platforms (January/February 2014)

It has long been known that the skiving process for machining internal gears is multiple times faster than shaping, and more flexible than broaching, due to skiving's continuous chip removal capability. However, skiving has always presented a challenge to machines and tools. With the relatively low dynamic stiffness in the gear trains of mechanical machines, as well as the fast wear of uncoated cutters, skiving of cylindrical gears never achieved acceptance in shaping or hobbing, until recently.

120 Hardening Technology Focuses on Dimensional Accuracy (March/April 2014)

New technology from Eldec/EMAG helps control the induction hardening process.

121 Repair of High-Value, High-Demand Spiral Bevel Gears by Superfinishing (October 2012)

Following is a report on the R&D findings regarding remediation of high-value, high-demand spiral bevel gears for the UH–60 helicopter tail rotor drivetrain. As spiral bevel gears for the UH–60 helicopter are in generally High-Demand due to the needs of new aircraft production and the overhaul and repair of aircraft returning from service, acquisition of new spiral bevel gears in support of R&D activities is very challenging. To compensate, an assessment was done of a then-emerging superfinishing method—i.e., the micromachining process (MPP)—as a potential repair technique for spiral bevel gears, as well as a way to enhance their performance and durability. The results are described in this paper.

122 Case Study Involving Surface Durability and Improved Surface Finish (August 2012)

Gear tooth wear and micropitting are very difficult phenomena to predict analytically. The failure mode of micropitting is closely correlated to the lambda ratio. Micropitting can be the limiting design parameter for long-term durability. Also, the failure mode of micropitting can progress to wear or macropitting, and then go on to manifest more severe failure modes, such as bending. The results of a gearbox test and manufacturing process development program will be presented to evaluate super-finishing and its impact on micropitting.

123 Properties of Tooth Surfaces due to Gear Honing with Electroplated Tools (November/December 2001)

In recent years, the demands for load capacity and fatigue life of gears constantly increased while weight and volume had to be reduced. To achieve those aims, most of today's gear wheels are heat treated so tooth surfaces will have high wear resistance. As a consequence of heat treatment, distortion unavoidably occurs. With the high geometrical accuracy and quality required for gears, a hard machining process is needed that generates favorable properties on the tooth surfaces and the near-surface material with high reliability.

124 Sigma Pool Encourages Collaboration at 2009 U.S. Gear Seminar (July 2009)

In the past, the coffee breaks and dinner events at Sigma Pool’s gear seminars have often triggered future process development and product improvements. This was still the case during the 2009 installment where customers and suppliers talked shop inside and outside the banquet hall on the new market and technology challenges currently facing the gear industry.

125 Technology Tidbits (January/February 2002)

New Technique for Forging Crowned Helical Gears Createch Co. Ltd., a forging die manufacturer from Shizuoka, Japan, has developed a net-shape cold-forging process for forming helical gears and splines with crowned teeth.

126 Dry Machining for Gear Shaping (November/December 2001)

Economic production is one of the main concerns of any manufacturing facility. In recent years, cost increases and tougher statutory requirements have increasingly made cutting fluids a problematic manufacturing and cost factor in metalworking. Depending on the cutting fluid, production process and supply unit, cutting-fluid costs may account for up to 16% of workpiece cost. In some cases, they exceed tool cost by many times (Ref. 1). The response by manufacturers is to demand techniques for dry machining (Ref. 2).

127 Technological Fundamentals of CBN Bevel Gear Finish Grinding (November/December 1985)

The bevel gear grinding process, with conventional wheels, has been limited to applications where the highest level of quality is required.

128 Hob Length Effects (September/October 1985)

Hobbing is probably the most popular gear manufacturing process. Its inherent accuracy and productivity makes it a logical choice for a wide range of sizes.

129 The Effect of Metallurgy on the Performance of Carburized Gears (March/April 1996)

Gears are designed to be manufactured, processed and used without failure throughout the design life of the gear. One of INFAC's objectives (*see p.24) is to help manufacture of gears to optimize performance and life. One way to achieve this is to identify failure mechanisms and then devise strategies to overcome them by modifying the manufacturing parameters.

130 Green Heat Treating - No Sweat (November/December 2009)

Bob McCulley of Comprehensive Heat Treat Specialists describes how even the most energy intensive industrial processes can be made "green."

131 Atmospher vs. Vacuum Carburizing (March/April 2002)

In recent years, improvements in the reliability of the vacuum carburizing process have allowed its benefits to be realized in high-volume, critical component manufacturing operations. The result: parts with enhanced hardness and mechanical properties.

132 Effects of Axle Deflection and Tooth Flank Modification on Hypoid Gear Stress Distribution and Contact Fatigue Life (August 2009)

As is well known in involute gearing, “perfect” involute gears never work perfectly in the real world. Flank modifications are often made to overcome the influences of errors coming from manufacturing and assembly processes as well as deflections of the system. The same discipline applies to hypoid gears.

133 Spiral Bevel and Hypoid Gear Cutting Technology Update (July 2007)

Spiral bevel and hypoid gear cutting has changed significantly over the years. The machines, tools, processes and coatings have steadily advanced.

134 Cutting Hardened Gears (November/December 2002)

The need for improved power transmissions that use gears and gearboxes with smaller overall dimensions and with lower noise generation has left manufacturing engineers searching for different methods of gear processing. This search has led to the requirement of hardened gears.

135 Engineered Gear Steels: A Review (November/December 2002)

The selection of the proper steel for a given gear application is dependent on many factors. This paper discusses the many aspects related to material, design, manufacture, and application variables. The results of several studies on the optimization of alloy design for gas- and plasma- carburization processing and reviewed.

136 Gear Surface Durability Development to Enhance Transmission Power Density (July/August 2002)

Gear pitting is one of the primary failure modes of automotive transmission gear sets. Over the past years, many alternatives have been intended to improve their gear surface durability. However, due to the nature of new process development, it takes a length of time and joint efforts between the development team and suppliers to investigate and verify each new approach.

137 Gear Grinding 2003 (November/December 2003)

The benefits of ground gears are well known. They create less noise, transmit more power and have longer lives than non-ground gears. But grinding has always been thought of as an expensive process, one that was necessary only for aerospace or other high-tech gear manufacturing.

138 Don't Panic (July/August 2000)

I'm a big believer in the value of IMTS as a marketplace where gear manufacturers can go and look at the latest machine tools and processes; compare hobbing machines, gear grinders and inspection equipment; see turning, milling or grinding machines in action; and ask questions of the various vendors all in one place. This year's IMTS promised to be the biggest ever, and I have no doubt that it will be a valuable experience to those who go there looking for ways to improve the way they manufacture products.

139 The Next Step in Bevel Gear Metrology (January/February 1996)

In recent years, gear inspection requirements have changed considerably, but inspection methods have barely kept pace. The gap is especially noticeable in bevel gears, whose geometry has always made testing them a complicated, expensive and time-consuming process. Present roll test methods for determining flank form and quality of gear sets are hardly applicable to bevel gears at all, and the time, expense and sophistication required for coordinate measurement has limited its use to gear development, with only sampling occurring during production.

140 Checking Large Gears (March/April 1987)

Gear manufacturing schedules that provide both quality and economy are dependent on efficient quality control techniques with reliable measuring equipment. Given the multitude of possible gear deviations, which can be found only by systematic and detailed measuring of the gear teeth, adequate quality control systems are needed. This is especially true for large gears, on which remachining or rejected workpieces create very high costs. First, observation of the gears allows adjustment of the settings on the equipment right at the beginning of the process and helps to avoid unproductive working cycles. Second, the knowledge of deviations produced on the workpiece helps disclose chance inadequacies on the production side: e.g., faults in the machines and tools used, and provides an opportunity to remedy them.

141 Rotary Gear Honing (May/June 1987)

Rotary gear honing is a hard gear finishing process that was developed to improve the sound characteristics of hardened gears by: Removing nicks and burrs; improving surface finish; and making minor corrections in tooth irregularities caused by heat-treat distortion.

142 Hard Gear Finishing (March/April 1988)

Hard Gear Finishing (HGF), a relatively new technology, represents an advance in gear process engineering. The use of Computer Numerical Controlled (CNC) equipment ensures a high precision synchronous relationship between the tool spindle and the work spindle as well as other motions, thereby eliminating the need for gear trains. A hard gear finishing machine eliminates problems encountered in two conventional methods - gear shaving, which cannot completely correct gear errors in gear teeth, and gear rolling, which lacks the ability to remove stock and also drives the workpiece without a geared relationship to the master rolling gear. Such a machine provides greater accuracy, reducing the need for conventional gear crowning, which results in gears of greater face width than necessary.

143 Distortion Control by Innovative Heat Treating Technologies in the Automotive Industry (August 2008)

The proper control of distortion after thermal treatment of powertrain components in the automotive industry is an important measure in ensuring high-quality parts and minimizing subsequent hard machining processes in order to reduce overall production costs.

144 Selection of Material and Compatible Heat Treatments for Gearing (May/June 1986)

The manufacturing process to produce a gear essentially consist of: material selection, blank preshaping, tooth shaping, heat treatment, and final shaping. Only by carefully integrating of the various operations into a complete manufacturing system can an optimum gear be obtained. The final application of the gear will determine what strength characteristics will be required which subsequently determine the material and heat treatments.

145 Economics of CNC Gear Gashing vs. Large D.P. Hobbing (August/September 1984)

Gear gashing is a gear machining process, very much like gear milling, utilizing the principle of cutting one or more tooth (or tooth space) at a time. The term "GASHING" today applies to the roughing, or roughing and finishing, of coarse diametral pitch gears and sprockets. Manufacturing these large coarse gears by conventional methods of rough and finish hobbing can lead to very long machining cycles and uneconomical machine utilization.

146 CNC Gear Shaping (March/April 1986)

Two major processes used for cutting gears, hobbing and shaping. This article describes advanced machine design and cutter materials for gear shaping.

147 Enhanced Product Performance--Through CBN Grinding (September/October 1988)

Modern manufacturing processes have become an ally of the product designer in producing higher quality, higher performing components in the transportation industry. This is particularly true in grinding systems where the physical properties of CBN abrasives have been applied to improving cycle times, dimensional consistency, surface integrity and overall costs. Of these four factors, surface integrity offers the greatest potential for influencing the actual design of highly stressed, hardened steel components.

148 Crowned Spur Gears: Optimal Geometry and Generation (September/October 1988)

Involute spur gears are very sensitive to gear misalignment. Misalignment will cause the shift of the bearing contact toward the edge of the gear tooth surfaces and transmission errors that increase gear noise. Many efforts have been made to improve the bearing contact of misaligned spur gears by crowning the pinion tooth surface. Wildhaber(1) had proposed various methods of crowning that can be achieved in the process of gear generation. Maag engineers have used crowning for making longitudinal corrections (Fig. 1a); modifying involute tooth profile uniformly across the face width (Fig. 1b); combining these two functions in Fig. 1c and performing topological modification (Fig. 1d) that can provide any deviation of the crowned tooth surface from a regular involute surface. (2)

149 Achievable Carburizing Specifications (January/February 1990)

A widespread weakness of gear drawings is the requirements called out for carburize heat treating operations. The use of heat treating specifications is a recommended solution to this problem. First of all, these specifications guide the designer to a proper callout. Secondly, they insure that certain metallurgical characteristics, and even to some extent processing, will be obtained to provide the required qualities in the hardened gear. A suggested structure of carburizing specifications is give.

150 Guidelines for Modern Bevel Gear Grinding (August 2008)

This paper acknowledges the wide variety of manufacturing processes--especially in grinding--utlized in the production of bevel gears...

151 Compter-Aided Spur Gear Tooth Design: An Application-Driven Approach (November/December 1989)

This article discusses an application driven approach to the computer-aided sizing of spur gear teeth. The methodology is bases on the index of tooth loading and environment of application of the gear. It employs handbook knowledge and empirical information to facilitate the design process for a novice. Results show that the approach is in agreement with the textbook data. However, this technique requires less expert knowledge to arrive at the conclusion. The methodology has been successfully implemented as a gear tooth sizing module of a parallel axis gear drive expert system.

152 Systematic Approach to Desinging Plastic Spur and Helical Gears (November/December 1989)

Plastic gears are being used increasingly in applications, such as printers, cameras, small household appliances, small power tools, instruments, timers, counters and various other products. Because of the many variables involved, an engineer who designs gear trains on an occasional basis may find the design process to be somewhat overwhelming. This article outlines a systematic design approach for developing injection molded plastic spur and helical gears. The use of a computer program for designing plastic gears is introduced as an invaluable design tool for solving complex gearing equations.

153 Calculation of Optimum Tooth Flank Corrections for Helical Gears (September/October 1988)

The load carrying behavior of gears is strongly influenced by local stress concentrations in the tooth root and by Hertzian pressure peaks in the tooth flanks produced by geometric deviations associated with manufacturing, assembly and deformation processes. The dynamic effects within the mesh are essentially determined by the engagement shock, the parametric excitation and also by the deviant tooth geometry.

154 Estimating Hobbing Times (July/August 1989)

Hobbing is a continuous gear generation process widely used in the industry for high or low volume production of external cylindrical gears. Depending on the tooth size, gears and splines are hobbed in a single pass or in a two-pass cycle consisting of a roughing cut followed by a finishing cut. State-of-the-art hobbing machines have the capability to vary cutting parameters between first and second cut so that a different formula is used to calculate cycle times for single-cut and double-cut hobbing.

155 CNC Controlled CBN Form Grinding (May/June 1984)

Borazon is a superabrasive material originally developed by General Electric in 1969. It is a high performance material for machining of high alloy ferrous and super alloy materials. Borazon CBN - Cubic Born Nitride - is manufactured with a high temperature, high pressure process similar to that utilized with man-made diamond. Borazon is, next to diamond, the hardest abrasive known; it is more than twice as hard as aluminum oxide. It has an extremely high thermal strength compared to diamond. It is also much less chemically reactive with iron, cobalt or nickel alloys.

156 Advantages of Titanium Nitride Coated Gear Tools (May/June 1984)

A brief introduction to the subject of Thin Film Coatings and their application to gear hobs and shaper cutters is followed by a detailed description of the Chemical Vapor Deposition Process and the Physical Vapor Deposition Process. Advantages and disadvantages of each of these processes is discussed. Emphasis is placed upon: application engineering of coated gear tools based on laboratory and field test results. Recommendations are suggested for tool design improvements and optimization of gear cutting operations using coated tools. Productivity improvements potentially available by properly utilizing coated tools are considered in terms of both tool cost and machining cost.

157 Zerol Bevel Gears: Tribology Aspects in Angular Transmission Systems, Part III (November/December 2010)

Zerol bevel gears are the special case of spiral bevel gears with a spiral angle of 0°. They are manufactured in a single-indexing face milling process with large cutter diameters, an extra deep tooth profile and tapered tooth depth.

158 Carl Zeiss CMM Guides Andrew Tool with Complex Mars Rover Project (March/April 2011)

At Andrew Tool, CMMs have been an integral part of their manufacturing processes for years, but they had never faced a project with such intricate measurements, tight tolerances, heat treatments and a very short time frame requirement.

159 Induction Heat Treating Gains Ground through Advances in Technology (March/April 2011)

In recent years, there has been significant interest in expanding the use of induction hardening in gear manufacturing operations. Over the past several years, many of the limits to induction hardening have shrunk, thanks to recent advances in technology, materials and processing techniques.

160 Heller Introduces Gear Manufacturing on Five-Axis Milling Machines (August 2010)

In co-operation with Voith, a major transmission manufacturer in Germany, Heller has developed a process that significantly enhances the productivity of pre-milling and gear milling operations performed on a single 5-axis machining center.

161 Raising the Standards (August 2010)

Dr. Phil Terry, chairman of the AGMA Technical Division Executive Committee, talks about the standards-making process.

162 Single-Pass Honing Holds the Line on PM Sprockets (June 2010)

Bore finishing system from Sunnen helps Cloyes Gear and Products achieve high accuracy, productivity and process capability.

163 Bending Fatigue, Impact and Pitting Resistance of Ausform-Finished PM Gears (June 2010)

The powder metal (P/M) process is making inroads in automotive transmission applications due to substantially lower costs of P/M-steel components for high-volume production, as compared to wrought or forged steel parts. Although P/M gears are increasingly used in powered hand tools, gear pumps and as accessory components in automotive transmissions, P/M-steel gears are currently in limited use in vehicle transmission applications. The primary objective of this project was to develop high-strength P/M-steel gears with bending fatigue, impact resistance and pitting fatigue performance equivalent to current wrought steel gears.

164 Lapping and Superfinishing Effects on Surface Finish of Hypoid Gears and Transmission Errors (September/October 2008)

This presentation is an expansion of a previous study (Ref.1) by the authors on lapping effects on surface finish and transmission errors. It documents the effects of the superfinishing process on hypoid gears, surface finish and transmission errors.

165 Manufacturing Method of Large-Sized Spiral Bevel Gears in Cyclo-Palloid System Using Multi-Axis Control and Multi-Tasking Machine Tool (August 2011)

In this article, the authors calculated the numerical coordinates on the tooth surfaces of spiral bevel gears and then modeled the tooth profiles using a 3-D CAD system. They then manufactured the large-sized spiral bevel gears based on a CAM process using multi-axis control and multi-tasking machine tooling. The real tooth surfaces were measured using a coordinate measuring machine and the tooth flank form errors were detected using the measured coordinates. Moreover, the gears were meshed with each other and the tooth contact patterns were investigated. As a result, the validity of this manufacturing method was confirmed.

166 Liebherr's LDF350 Offers Complete Machining in New Dimension (November/December 2011)

The objective, according to Dr.- Ing. Hansjörg Geiser, head of development and design for gear machines at Liebherr, was to develop and design a combined turning and hobbing machine in which turning, drilling and hobbing work could be carried out in the same clamping arrangement as the hobbing of the gearings and the subsequent chamfering and deburring processes.

167 The Staying Power of Low-Pressure Carburizing (September/October 2008)

Open any heat treating journal today and you’re certain to find multiple references (articles, technical papers and/or advertisements) promoting low-pressure carburizing (LPC). The uninformed might breeze by these references thinking it’s the next flash-in-the-pan, but unlike in the past, this time the process has legs.

168 Induction Hardening of Gears and Critical Components - Part I (September/October 2008)

Induction hardening is a heat treating technique that can be used to selectively harden portions of a gear, such as the flanks, roots and tips of teeth, providing improved hardness, wear resistance, and contact fatigue strength without affecting the metallurgy of the core and other parts of the component that don’t require change. This article provides an overview of the process and special considerations for heat treating gears. Part I covers gear materials, desired microsctructure, coil design and tooth-by-tooth induction hardening.

169 Comparison of Test Rig and Field Measurement Results on Gearboxes for Wind Turbines (October 2011)

This article describes some of the most important tests for prototypes conducted at Winergy AG during the product development process. It will demonstrate that the measurement results on the test rig for load distribution are in accordance with the turbine measurements.

170 State-of-the-Art Broaching (August 2011)

There are a number of companies working to change the way broaching is perceived, and over the past 10 years, they’ve incorporated significant technological changes to make the process more flexible, productive and accurate.

171 2011 AGMA Fall Technical Meeting (September 2011)

The AGMA Fall Technical Meeting provides an opportunity to share ideas with others on the design, analysis, manufacturing and application of gears, gear drives, and related products, as well as associated processes and procedures.

172 Manufacturing Net-Shaped, Cold-Formed Gears (May 2008)

A net-shaped metal forming process has been developed for manufacturing quality, durable, high-yield and cost-efficient gears for high-volume production.

173 Material Integrity in Molded Plastic Gears and its Dependence on Molding Practices (June 2008)

The quality of molded plastic gears is typically judged by dimensional feature measurements only. This practice overlooks potential deficiencies in the molding process.

174 Carbide Rehobbing A New Technology That Works! (May/June 1994)

Many people in the gear industry have heard of skiving, a process wherein solid carbide or inserted carbide blade hobs with 15 - 60 degrees of negative rake are used to recut gears to 62 Rc. The topic of this article is the use of neutral (zero) rake solid carbide hobs to remove heat treat distortion, achieving accuracies of AGMA 8 to AGMA 14, DIN 10-5 and improving surface finish on gears from 8 DP - 96 DP (.3 module - .26 m.).

175 Choosing An ISO 9000 Consultant: Why, When & How (May/June 1994)

On of the key questions confronting any company considering ISO 9000 certification is, how much is this going to cost? The up-front fees are only the beginning. Dissect the ISO 9000 certification procedure with an eye for hidden costs, and two segments of the process will leap out - the cost of consultants and the cost of making in-house improvements for the sake of passing certification. Most of these costs can be controlled by careful selection f the right consultant in the first place.

176 New Innovations in Hobbing - Part I (September/October 1994)

Prior to the introduction of titanium nitride to the cutting tool industry in the early 1980s, there was very little progress in the general application of hobbing in the gear cutting industry. The productivity gains realized with this new type of coating initiated a very active time of advancement in the gear manufacturing process.

177 Investigation of Surface Layer and Wear Behavior of Nitrided Gear Drives (March/April 1994)

In this article we will characterize the nitride layers that are generated by different nitriding processes and compare their respective wear characteristics.

178 Captive vs. Commercial Heat Treaters? A Split Decision (August 2007)

Heat treating is a vital step in the gear making process—that’s a given. But how that step is taken can happen in a number of ways.

179 Hob Basics Part I (September/October 1993)

The Hobbing Process The hobbing process involves a hob which is threaded with a lead and is rotated in conjunction with the gear blank at a ratio dependent upon the number of teeth to be cut. A single thread hob cutting a 40-tooth gear will make 40 revolutions for each revolution of the gear. The cutting action in hobbing is continuous, and the teeth are formed in one passage of the hob through the blank. See Fig. 1 for a drawing of a typical hob with some common nomenclature.

180 Innovative CNC Gear Shaping (January/February 1994)

The Shaping Process - A Quick Review of the Working Principle. In the shaping process, cutter and workpiece represent a drive with parallel axes rotating in mesh (generating motion) according to the number of teeth in both cutter and workpiece (Fig. 1), while the cutter reciprocates for the metal removal action (cutting motion).

181 Optimal Choice of the Shaft Angle for Involute Gear Hobbing (November/December 2007)

With reference to the machining of an involute spur or helical gear by the hobbing process, this paper suggests a new criterion for selecting the position of the hob axis relative to the gear axis.

182 Quality Gear Inspection - Part I (September/October 1994)

Quality gear inspection means doing the "right" inspections "right." A lot of time and money can be spent doing the wrong types of inspections related to function and doing them incorrectly. As we will discover later, such things as runout can creep into the manufacturing and inspection process and completely ruin any piece of data that is taken. this is one of the most important problems to control for quality inspection.

183 Computer Aided Design (CAD) of Forging and Extrusion Dies for the Production of Gears by Forming (January/February 1985)

Material losses and long production times are two areas of conventional spur and helical gear manufacturing in which improvements can be made. Metalforming processes have been considered for manufacturing spur and helical gears, but these are costly due to the development times necessary for each new part design. Through a project funded by the U.S. Army Tank - Automotive Command, Battelle's Columbus Division has developed a technique for designing spur and helical gear forging and extrusion dies using computer aided techniques.

184 The Shape of Things to Come (July/August 1995)

An engineer's responsibility for verifying a new design or product concept as manufacturable early in the development cycle is a tough challenge. What appears to work on a blueprint or in a three-dimensional CAD file on a computer screen many not work on the factory floor; and the downstream impact on the manufacturing process of an undetected design flaw can be enormous. Costs can run into the millions.

185 Drivetrain Research An Idea Whose Time is Overdue (July/August 1995)

The popular perception today is that technological advancement is an engine running almost out of control. New products and processes are developing faster than we can keep up with them, as anyone who has had a new computer system crash into obsolescence practically before it's out of the box can tell you. But that's not the case everywhere. Transmission technology, for example.

186 Producing Profile and Lead Modifications in Threaded Wheel and Profile Grinding (January/February 2010)

Modern gearboxes are characterized by high torque load demands, low running noise and compact design. In order to fulfill these demands, profile and lead modifications are being applied more often than in the past. This paper will focus on how to produce profile and lead modifications by using the two most common grinding processes—threaded wheel and profile grinding. In addition, more difficult modifications—such as defined flank twist or topological flank corrections—will also be described in this paper.

187 Surface Damage Caused by Gear Profile Grinding and its Effects on Flank Load Carrying Capacity (September/October 2004)

Instances of damage to discontinuous form ground and surface-hardened gears, especially of large scale, have recently increased. This may be attributed partly to a faulty grinding process with negative effects on the surface zones and the surface properties.

188 How to Carburize a Finished Gear (March/April 1995)

Precise heat treatment plays an essential role in the production of quality carburized gears. Seemingly minor changes in the heat treating process can have significant effects on the quality, expense and production time of a gear, as we will demonstrate using a case study from one of our customer's gears.

189 Heat Treating Equipment Selection (March/April 1995)

For heat treatment of tool and alloy steels, the end-user has a wide range of basic types of heat treating equipment to choose from. This article reviews them and details the criteria that must be considered in selecting equipment for a specific application. In making this choice, the most important criterion must be the quality of the tool or part after processing.

190 Got Lean, Six Sigma - Here's Another Theory (March/April 2009)

Most readers are at least familiar with continuous improvement programs such as lean and six sigma. Perhaps your shop or company is well along in the implementation of one or the other—if not both. But what about theory of constraints (TOC), introduced in Dr. Eliyahu Goldratt’s 1984 book, The Goal? Despite its rather negative-sounding name, this continuous improvement process has much to offer manufacturers of all stripes. And when combined with lean and six sigma, the results can be dramatic. Dr. Lisa Lang, a TOC consultant and speaker, explains why and how in the following Q&A session with Gear Technology.

191 Shorter Cycle Times for Carburizing (March/April 2006)

Dana Corp. is developing a process that carburizes a straight bevel gear to a carbon content of 0.8% in 60 fewer minutes than atmosphere carburizing did with an identical straight bevel.

192 Robust Transmission Design Through Automated Optimization of Virtual Prototypes (January/February 2005)

Romax Technology is automating the design iteration process to allow companies to be faster to market with the highest quality, most robust gear products.

193 Influence of CBN Grinding on Quality and Endurance of Drive Train Components (January/February 1991)

The merits of CBN physical characteristics over conventional aluminum oxide abrasives in grinding performance are reviewed. Improved surface integrity and consistency in drive train products can be achieved by the high removal rate of the CBN grinding process. The influence of CBN wheel surface conditioning procedure on grinding performance is also discussed.

194 SPC Acceptance of Hobbing & Shaping Machines (September/October 1991)

Today, as part of filling a typical gear hobbing or shaping machine order, engineers are required to perform an SPC acceptance test. This SPC test, while it is contractually necessary for machine acceptance, is not a machine acceptance test. It is a process capability test. It is an acceptance of the machine, cutting tool, workholding fixture, and workpiece as integrated on the cutting machine, using a gear measuring machine, with its work arbor and evaluation software, to measure the acceptance elements of the workpiece.

195 Methodology for Translating Single-Tooth Bending Fatigue Data to be Comparable to Running Gear Data (March/April 2008)

A method to extrapolate running gear bending strength data from STF results for comparing bending performance of different materials and processes.

196 Operational Condition and Superfinishing Effect on High-Speed Helical Gearing System Performance (March/April 2008)

An experimental effort has been conducted on an aerospace-quality helical gear train to investigate the thermal behavior of the gear system. Test results from the parametric studies and the superfinishing process are presented.

197 Shaper Cutters - Design & Application - Part 2 (May/June 1990)

Cutter Sharpening Cutter sharpening is very important both during manufacturing and subsequently in resharpening after dulling. Not only does this process affect cutter "over cutting edge" quality and the quality of the part cut, but it can also affect the manner in which chip flow takes place on the cutter face if the surface finished is too rough or rippled.

198 Gear Finishing with a Nylon Lap (September/October 2005)

The objective of this research is to develop a new lapping process that can efficiently make tooth flanks of hardened steel gears smooth as a mirror.

199 What to Know About Bevel Gear Grinding (September/October 2005)

Guidelines are insurance against mistakes in the often detailed work of gear manufacturing. Gear engineers, after all, can't know all the steps for all the processes used in their factories.

200 A Study on Reducing Gear Tooth Profile Error by Finish Roll Forming (July/August 2005)

The authors have developed a rack-type rolling process in which a rack tool is used to roll gear teeth. The results and analysis show that the proposed method reduces errors.

201 New Approach to Computerized Design of Spur and Helical Gears (January/February 2005)

Applying "Dynamic Block Contours" allows the designer to predict gear quality at the earliest stage of the design process.

202 CNC Technology and the System-Independent Manufacture of Spiral Bevel Gears (September/October 1992)

CNC technology offers new opportunities for the manufacture of bevel gears. While traditionally the purchase of a specific machine at the same time determined a particular production system, CNC technology permits the processing of bevel gears using a wide variety of methods. The ideological dispute between "tapered tooth or parallel depth tooth" and "single indexing or continuous indexing" no longer leads to an irreversible fundamental decision. The systems have instead become penetrable, and with existing CNC machines, it is possible to select this or that system according to factual considerations at a later date.

203 Improving Gear Manufacturing Quality With Surface Texture Measurement (March/April 1993)

The working surfaces of gear teeth are often the result of several machining operations. The surface texture imparted by the manufacturing process affects many of the gear's functional characteristics. To ensure proper operation of the final assembly, a gear's surface texture characteristics, such as waviness and roughness, can be evaluated with modern metrology instruments.

204 Grinding of Spur and Helical Gears (July/August 1992)

Grinding is a technique of finish-machining, utilizing an abrasive wheel. The rotating abrasive wheel, which id generally of special shape or form, when made to bear against a cylindrical shaped workpiece, under a set of specific geometrical relationships, will produce a precision spur or helical gear. In most instances the workpiece will already have gear teeth cut on it by a primary process, such as hobbing or shaping. There are essentially two techniques for grinding gears: form and generation. The basic principles of these techniques, with their advantages and disadvantages, are presented in this section.

205 Technical Calendar (July/August 1986)

October 5-8, 1986 AGMA Fall technical Conference & Gearing Exhibit September 17-19, 1986 Ohio State University Gear Noise Seminar November 11-13, 1986 SME Gear Processing and Manufacturing Clinic November 19-21, 1986 Seminar: Gear System Design for Minimum Noise

206 Technical Calendar (November/December 1988)

November 1-3. SME Gear Processing and Manufacturing Clinic, Sheraton Meridian, Indianapolis, IN. November 5-10. international Conference on Gearing, Zhengzhou, China

207 Revolutions (March/April 2004)

"Gears of Gold" and "Process Equipment's Virtual ND430."

208 Technical Calendar (September/October 1988)

September 27-29. American Society for Metals 11th Annual Heat Treating Conference October 10-12. AGMA Fall Technical Meeting. Fairmont Hotel, New Orleans, LA November 1-3. SME Gear Processing and Manufacturing Clinic, Sheraton Meridian, Indianapolis, IN

209 The Winds of Change (January/February 1991)

Nashville - One of the highlights of this year's SME Advanced Gear Processing and Manufacturing Clinic was a tour of the new GM Saturn automobile manufacturing plant outside the city. There in the Tennessee hills is a hopeful vision of the future of the American automobile industry. It may well be the future of American large-scale manufacturing in general.

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Larry Ewald announced his retirement after 27 years at Process Equipment Co. In 1978, he succeeded the company's founder, Emmert Stud... Read News

16 Process Equipment Sold, President Retires (April 19, 2005)
Larry Ewald announced his retirement after 27 years at Process Equipment Co. In 1978, he succeeded the company’s founder, Emmert Stu... Read News

17 Cowley Hired as Sales Manager of Process Equipment (April 12, 2005)
Bruce Cowley was hired as sales manager for the metrology systems division of Process Equipment Co. According to the company's p... Read News

18 Nitrex Partners with Process Electronic (December 14, 2003)
Nitrex Metal, a supplier of nitriding and nitrocarburizing technologies, has entered into a partnership with Process Electronic GmbH, a G... Read News

19 Process Equipment Announces Partnerships (August 30, 2007)
Process Equipment Announces PartnershipsProcess Equipment Co. announced a distributorship agreement with Arthur Klick Co. for distributio... Read News

20 Applied Process Hosts First AP University (January 28, 2013)
More than 30 designers and engineers went “back to college” to learn how Austempered Ductile Iron (ADI) could work in their m... Read News

21 Applied Process Announces Promotions (February 20, 2013)
A new year and new titles have brought new opportunities and responsibilities for employees at Applied Process, Inc. as three senior staf... Read News

22 EMAG Offers Heat Shrink Assembly Process (July 17, 2013)
The composite camshaft is still gaining ground in the marketplace. The main reason for this is the considerable weight reduction it bring... Read News

23 U.S. Gear Contracts United Process Controls (July 6, 2010)
New furnace controls and data acquisition from United Process Controls have been ordered by U.S. Gear, a division of AxleTech Internation... Read News

24 Combined Process Machine Completes Cylindrical Gears (January 26, 2010)
The Agilus 180TH multi-functional machine from Gleason performs turning, drilling, milling, hobbing and chamfering/deburring operatio... Read News

25 Holroyd?s Plated CBN on High-Rigidity Edgetek Machines Reduces Process Times with Single Lift and Setup (February 14, 2007)
Holroyd's Edgetek machines are produced with high-power/high-speed spindles that optimize the use of plated CBN wheels at surface spe... Read News

26 Applied Process Commissions Heat Treating Facility in China (February 19, 2007)
Applied Process CEO John Keough recently commissioned AP Suzhou as the newest member of the Applied Process family of companies. The... Read News

27 Applied Process Takes on Majority Interest Partner (September 23, 2014)
Applied Process Inc. (AP) has taken on High Street Capital (HSC), Chicago, Ill., as a majority interest equity partner. This move adds es... Read News

28 Applied Process Chinese Operation Sets an Opening Date (April 14, 2006)
John Keough, CEO of Applied Process, announced that AP Suzhou, located in Suzhou, Jiangsu Province, China, will commence commercial auste... Read News