These specification guidelines for automated assembly systems will give you more consistency where consistency is beneficial, and more variety where variety can help you take your business to the next level.

In my last posting, I wrote about the differences between companies that are happy with their automation suppliers and those that aren’t. One of the big differences between those two groups is how they write specifications, so I thought I’d throw my two cents in on what makes a good specification from an equipment builder’s perspective.

I cannot overstate enough how important it is to have a good understanding of the product that is being assembled or tested. Concurrent engineering has significantly reduced the amount of hard information that’s provided in an RFQ package. As a result, equipment builders are forced to draw their own conclusions about the product design and make their own assumptions when developing station concepts.

Whether this is a strategy to tip responsibility for mistakes toward suppliers, or whether customers simply don’t have enough resources to make the assumptions themselves, it is one of the biggest sources of variation in quotation content during pre-award evaluations, and it’s a huge lightning rod of contention that saps project flow and hurts relationships after the contract is awarded. While you may argue that you are opening yourselves up for change orders by listing product design and process assumptions, you’ll have the same risk if the suppliers document their assumptions. At least if it comes from you, everyone is quoting to the same (and likely more reasonable) set of information, and you can better evaluate the proposed solutions.

Similarly, it’s also important to clarify tolerance assumptions for any part feature that affects a process being quoted. Almost all customers require a CpK or gauge R&R compliance statement, yet they supply virtually no tolerances on the product design. Since machine builders must have that information to determine what equipment is needed to meet the required statistical quality level, the quoting process becomes a contest of risk tolerance between suppliers, rather than a true test of their process understanding. This discrepancy could literally cause a line to be built that will never meet your needs.

Don’t specify what the equipment looks like. Instead, specify the outcomes you expect and the constraints your company operates under. Specify in terms of throughput, model mix, batch size, changeover times, shift patterns, equipment efficiencies, quality factors, labor costs, floor space constraints, current technologies, and the skill levels of operators and maintenance personnel.

Armed with that information, equipment suppliers can take advantage of their creativity and experience to give you the best system possible. You’ll get a more varied set of quotations, and the differences between the possible solutions will make a competitive evaluation more difficult. In the end, however, you’ll raise the bar on your operations by allowing for a step change in the way you do things.

There are exceptions. You may not want to take this approach if:
* your product families share a lot of commonality.
* your products are made at similar volumes.
* you already have a common assembly or test platform that you’re happy with.
* you’re a profitable market leader.

In that case, stick with what’s been working and specify equipment content. Even so, it wouldn’t hurt to open things up once in a while to see what other ideas are out there. And please, resist the urge to ask suppliers to quote both a required content solution and a secondary solution with their own ideas-unless you have six or seven weeks for the quoting cycle. Writing two full quotes in a “normal” cycle will only dilute the quality of both.

While we’re on the subject of time to do a quote, the quality of the quote you receive is directly proportional to the time we have to quote it. There is no magic bullet to change that equation. While the time between the initial RFQ and order placement has stretched out over the years (three to six months in many cases), the time that we have to provide most quotations has shrunk. Two-week requests are routine, and often they are even shorter than that. We cannot adequately come up with a sound concept, chase down vendor quotes, create costing, and produce a well-written document in that amount of time. The quality of the offering suffers to meet the deadline. Four weeks would allow for more creativity and better thoroughness. It may even reduce the overall time, because there will be fewer requotes and misunderstandings. This is a case where more is always better.

Provide a list of components (valves, PLCs, robots, etc.) that you are comfortable using. Identify those components that can’t be substituted due to spare parts inventories or in-house expertise, and those for which you might accept less expensive or more capable replacements.

Consolidate your specifications. Many companies have general company specifications, plant specifications, and sometimes even department specifications. Then, they add specifications for the program being quoted, to boot. When you have too many specifications for things like preferred components, safety, ergonomics, drawing standards, build standards, controls standards and mechanical standards, equipment suppliers quickly find themselves digging through a mountain of conflicting and confusing information with little hope of deciphering it all in the time allotted. (Back in the printed specification days, stack of papers could literally reach three or four feet high!) Again, this adds to uncertainty and variability in the quotations, and it creates conflicts during the project. More importantly, it costs you money for us to ensure compliance to standards that are only selectively enforced in most cases.

These guidelines will give you more consistency where consistency is beneficial, and more variety where variety can help you take your business to the next level. I welcome comments and other suggestions on the topic.

A 20-year veteran of the assembly automation industry, Bill Budde is regional director for corporate business development at Assembly & Test Worldwide Inc. in Dayton, OH. He holds a bachelor’s degree in electrical engineering from Kettering University and a master’s degree in international business and finance from Wright State University.

Editor’s note: “Budde on Assembly Automation” is one of a series of guest spots by industry experts that will appear regularly on ASSEMBLY’s blog page. Check back frequently to read more commentaries from Bill, as well as contributions on vision systems, leak testing, robotics and ergonomics.