There's one thing that I need to get off my chest early on in this blog, as it has been weighing on my mind for some time. It is the bane of my automotive life thus far, the PPAP.
Almost nobody knows or nor really cares these days that PPAP stands for "Production Parts Approval Process," nor that the system is responsible for terabytes of redundant data. The idea behind PPAPs is - I admit - sound, in that each and every part in a car is fully validated before being built into a vehicle. However, having worked on tube fittings for a few years and come across PPAP submissions "weighing" 26 megabytes for threaded nuts weighing 13 grammes, and still being wrong, I feel that the PPAP process itself needs investigating.
The PPAP is an information pack that includes the drawings, measurement data (with capability), test data, measurement and test equipment certification, FMEAs, control plans and process flows for the part in question. All of it needs to be correct to be accepted by the customer.
It was created by the AIAG (Automotive Industry Action Group) that originally consisted of the "Big" (now "Detroit") Three of Ford, GM and Chrysler. One of the driving principles behind it was to standardise the requirements for these three manufacturers so that their suppliers need only produce one data pack per part and not have to reproduce it with tweaks for each customer. The other key principle was and remains that parts will fit and work properly when they are assembled into the cars they are destined for. Equally, the PPAP should prove that the supplier is ready to produce good parts at volume and it provides baseline information for the life of the part ("back then at the beginning is was like that, now it's like this"). However, the PPAP system has become a monster. This monster has generated its own sub-industry; dedicated employees who work only on generating or approving PPAPs, and people like me checking supplier submissions like school teachers marking essays. There are great chains of PPAP submissions, from sub sub suppliers to suppliers to the OEMs, and the whole system is populated by disinterested humans.
The number of submissions that I have checked and rejected in the past for vast swathes of missing information was depressingly large. So these packs (of lies) are being batted back and forth from server to server, person to person and hours are being wasted the world over.
My relative fortune in my secret PPAP life was that I only had to check the technical aspect of the submissions; somebody else in the quality department was responsible for going through all the other documents and certificates (generally "is there something here that looks like a certificate, or not?"). But even the technical side of things, which really should have been simple, always seemed to lead to confusion.
Why should it be simple? Well, there are drawings with dimensions (some with complicated GD&T, admittedly, but still doeable) that need to be measured (and not just reported with the value "OK"). The supplier just needs to check off the dimensions one by one and show that what is being produced on real parts meets those requirements. Fine. But, the drawings also have words on them, sometimes in the form of specifications, which should give the supplier a small hint about some other aspect concerning the parts - like, say, performance - but often somehow don't. Maybe it is actually all just too subtle and not simple at all. It was alas very rare in my experience to receive a PPAP and to be able to complete it there and then, on the spot, no more questions asked. So not only do the PPAP submissions need to be sent along the chain of suppliers, they need to be reworked and resubmitted. Usually this involves testing being (re-) started just as the parts are urgently required, which means that we have to grant deviations for a limited period until all of the testing is completed (corrosion testing, anybody?), we have to request deviations of our customers and we have to keep track of those deviations as well as the versions of those PPAP documents... and so on.
So, there's lots's of time wasted, there are megabytes of redundant and duplicated information sloshing around, repeated for each of the approximately 15000 unique parts in each and every car driving around the world (I'm not sure PPAPs are used by Khodro in Iran, however).
And yet, PPAPs, like audits, are impossible to argue against. I recall hearing that Continental tried to settle on a basic level of PPAP above which the customer would have to pay, but I think that rebellion was quickly crushed. If you've heard more about it, let me know in the comments.
In the end, my recommendation is that, if you're a young budding engineer looking for a first job, try to avoid anything that says "PPAP" on it. If you still want the job, then make sure that the PPAP bit is not too high a percentage of the job and is for a limited period only - and spend that time finding someone else who will do it for you (preferably not an engineer!).