Gear Design: Defining the Goal

A critical step to having a successful project is defining the objective. Seems like a simple concept, but it is often overlooked or so poorly executed that the product is disowned long before it gets completed. I was not a true believer in ISO 9000 systems at first and only complied because the boss required participation. With the benefit of hindsight, I now see the wisdom of having written procedures and checklists along with periodic audits to keep you on track. Setting a goal, defining your inputs, establishing “rules,” and then making certain that the rules are followed insures that the entire team is pulling in the same direction and making efficient use of the organization’s resources. One of the best things we added to our gearbox catalog was a page full of questions about the gearbox to be built. It was a shorter version of the one we required customers to fill out and sign before we gave them a formal proposal drawing to kick off a project. I am not sure if it is still available, but the American Petroleum Institute [API] had a wonderful three-page document [SP-613-1, -2, & -3] that allowed you to accurately define an entire drive system including the prime mover, couplings, and driven equipment. A complete system description protects all parties from misunderstandings later. The designers get enough information to check for system dynamics issues, develop a duty cycle, and define the interface requirements. The customer gets assurance that their requirements are fully disclosed and can assess the experience level of the designers by the questions they ask. Everyone is protected from the dreaded “mission creep.” Mission creep is when one of the parties decides a few new requirements have been added after the project has started. If it was not in the product specification each party signed, then re-negotiation of the purchase order has to be completed before work can proceed. We’ll look at some key items for product specifications next week.