Among the various day-to-day tasks for purchasing personnel are meetings with vendors and manufacturer's reps. Occasionally, the buyer will be asked by the vendor or rep for an opportunity to provide a second source for the parts that are on the company's Approved Vendors List (AVL) or Approved Manufacturers List (AML).
Given that it is always good discipline to have alternate sources for as many parts as possible in the Item Master, these few minutes with the potential second-source vendor have a very real potential for saving the company time and money, specifically in the instance where the original part on the AVL cannot be sourced when needed.
However, there are dangers to consider. The vendor wants to win any additional business, so unless you are on your technical toes, the possibility of getting incorrect "alternate" parts is high. The vendor may truly believe its parts are identical substitutes, but because it's not intimate with your designs or any of the electrical and physical parameters of your circuit requirements, the suggested alternates may be unsuitable.
Think of a PC mount, right angle, 9-Pin, male D-sub connector. Well, we all have them on our home computer, modem, or some other piece of common electronic equipment, so we are tempted to think, "You've seen one, and you've seen them all!" This is not the case. Usually the connector protrudes through a back panel at a specific height off the PCB. What if the standard D-sub has no standard height measurement from manufacturer to manufacturer? Obviously, there is a high possibility that the board stuffers won't catch the measurement difference, but as soon as the back panel is included in the assembly, you find the D-sub connector opening is misaligned and the connector cannot protrude through. I have seen this time and again with connectors from offshore manufacturers.
So, what happened? Your visiting vendor didn't do this on purpose. Obviously, some people did not do their homework. The purchasing person may not have the background knowledge or experience to look at all the part details and compare them with the AVL-listed part specifications, and because this second-source checking can become fairly involved, someone in the company has to be responsible for every part's approval before admittance to the AVL as an alternate part. This can be a very time-consuming process, so the more specific the work that can be pushed back to the vendor, the more efficient the internal qualification process becomes.
One standard operating procedure that I have used is to ask the vendor to download and complete this Sample Part Request form and attach one copy to every part being submitted for AVL qualification. I usually have all the candidate parts and forms in-house within two weeks after the initial meeting with the vendor. As you might imagine, the fields on the form for each part give a very early indication whether the parts would make suitable substitutes and warrant further investigation.
Let's look at what part specifications and requirements the form fields cover.
- Contact information: This includes representative/vendor name, company, address, phone, fax, email address, and who they made contact with in my company along with the date of this submittal.
- Part identification: Manufacturer's name, part number, description, and package case style.
- My company's internal part number: Manufacturer's name and part number the vendor is trying to match.
- Quality assurance issues: Temperature grade (commercial, military, or industrial), FIT/MTBF (reliability), and other -- specify.
- Availability: Current lead-time, sole source (yes/no), production quantities available now, how long the part has been in production, anticipated end-of-life, availability through factory/distributor, name and phone numbers of distributors also carrying this part.
- Cost information at quantities: Budgetary – 100-250-500-1000-2500-5000-25,000, 50,000, and 100,000 plus.
- Literature: Attach data sheet and any application notes.
- Sample count: How many parts they are submitting for qualification, recommended handling procedures.
Now, you can quickly review the form and see if there is a business case for spending the time to qualify the parts.
With the specification sheets attached to the parts, you are now ready to forward this to component engineering to begin the internal process for tracking and testing the vendor's samples. Also, if you have assigned these forms and parts to a numbered Components Evaluation Request form, when the vendor calls you can quickly update him or her on the status of the qualification activities. All the preliminary verification work was performed by the vendor on his nickel and time.
You now have a hard copy record of critical business data for each part. You now have a means for quickly analyzing cost, availability, and lead-times. And, you now have an auditable, time- and resource-sensitive process underway with engineering because your accompanying CER form has a requested "complete by" date. When the vendor calls, you can quickly call engineering and ask for a progress report on CER #XXX and assess the progress quickly.
My next article will discuss the CER form and how to use it for maximum benefit.