Home | Advertise | Subscribe

Magazine | Newsletter | Product Alerts | Blog

How to Conduct a Heat Treat Audit

by Daniel H. Herring

Daniel H. Herring

Daniel H. Herring,
"The Heat Treat Doctor."

This article first appeared in Industrial Heating magazine

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.

The audit process should be designed to ask basic questions, e.g.:

What Constitutes a Good Audit?
Most audits that "fail" do so because they do not reveal the true nature of what is happening within the heat treatment operation. Care must be taken to look at both the quality aspects (forms, instructions, compliance) and the performance aspects (process control, work handling, etc.). Too often, audits focus their attention on the former and give a cursory look at the latter. This disconnect is the reason many organizations are confused as to why their departments or suppliers fail to achieve continuous improvement.

To be useful, heat treat audits need to ask tough and realistic questions—not just be forms in which the auditor fills in the blanks. The true story is revealed only in the details. It is critical that audits "drill down" to the level that the work is being done; meaning, a good heat treat audit spends less time in the office than on the shop floor. Finally, auditors must reward well-run operations and not hesitate to give them top scores when deserved. Here's a look at some of the critical information necessary for conducting a meaningful, comprehensive audit.

General (company/department profile)

Capabilities (general requirements)

Instructions (for auditors)

Sample Rating Guidelines (for audit questions)

Continuous Improvement Program (areas to review)

Audit FAQs

Non-Conformance (document, in detail)

Corrective Action (for each supplier location)

A Look at CQI-9
A new automotive industry action group (AIAG) heat treat audit guideline—CQI-9, Special Process: Heat Treat System Assessment—was released in March 2006. It is intended to help standardize the heat treat audit process. The HTSA supports the automotive process approach as described in ISO/TS 16949:2002.

Within each audit area, the major sections covered are: (1) process and test equipment requirements; (2) pyrometry; (3) process monitoring frequencies; (4) in-process/final test frequencies; and (5) quenchant and solution test frequencies.

Summing Up
Heat treat audits are so important that, in this writer's opinion, they need to be conducted by trained and certified heat treat personnel—not just auditors skilled in the procedures involved. Both captive and commercial heat treatment organizations should demand that this aspect of their business be given the attention and respect it deserves. A standardized audit guideline with fixed frequency of compliance is long overdue. With ever-increasing product performance demands from our customers, only continuous improvement will assure the heat treatment industry of continued growth and prosperity.

For more information:
Daniel H. Herring
The Herring Group Inc.
(630) 834-3017