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June 2014 • SMT Magazine 93 The eSSenTial pioneer'S SurViVal guide tronicsis continuously expanding. The expan- sion has stimulated the move into automotive for many new and existing companies who have not previously worked in the automotive segment. They face a significant learning curve to understand the requirements and implement the necessary standards of operation required. Legacy Automotive Practices The reality for the manufacture of almost all complex products is that in many cases, the end manufacturers themselves are not the original source of the faults. Issues often lie with the pro- viders of the many sub-assemblies, which can include dozens of individual microcomputer controllers of critical safety systems, which to- day are heading towards making up almost 40% of the value of a car. The automotive industry defined the original requirements for traceabil- ity, and they were extended to the suppliers of critical sub-assemblies. In their day, these led the way for much of the rest of the electronics manufacturing industry. The solutions that were adopted, going back to the 1980s, still in common use today, were founded upon solid industrial engineering practices of the time. It was based on two key principles: qualification and traceability. Qualification consists first of all on fully document- ed and planned procedures, materials, and operational practice. All possibility of variation is removed, elimi- nating all possible sources of variation and human er- ror. Once the operations were fixed, the qualified manufacturing line would create sample products which then were rigorously life-tested, often taking several weeks, until there was a negligible risk of fail- ure. Until this process was completed, no prod- ucts could actually be made. The line could not ever be used for any other purpose and was ef- fectively tied in and dedicated to producing the specific product to which it was assigned. There was no flexibility; the performance of the line had to meet the peak demand requirements, and at other times would run at a reduced pro- ductivity. Long-term commitment, determined by contractual agreement, would limit the vari- ation in demand so as to allow a reasonable chance of profitability; but in doing so, it sim- ply pushed the burden of dealing with fluctua- tion on to the car maker themselves. In many cases, the burden could not be shared, such as with Toyota in Japan, who would only accept sub-assemblies as needed. The second principle that automotive adopt- ed was traceability. The information technology available at the time was mainly paper based, written by humans. Although primitive, it was fully flexible and had little perceived cost. In re- ality, however, the small but frequent overhead for data recording, collating, and cross-referenc- ing became a major burden. Paper does not suf- fer from issues related to digital data storage, but it does require significant space and very careful management. The storage of paper for traceabil- ity has yielded amazing stories over the years, including one case where a large manufacturing site, with a circumference of almost a kilometre, had two floors; the ground floor was SMT and assembly produc- tion, and the lower ground floor was simply an archive area for the paper traceabil- ity records. Fire risks meant that the air had to be re- placed with nitrogen, except when people had to go "into the vaults" to find the paper trail of events where an issue had been discovered. It could take months to piece together all of the paper records to find the extent and scope of an issue that may be serious enough to trigger a recall event. To industrial engineers working outside the automotive segment, these practices were far in advance of other areas, and seemed un- acceptably restrictive. Consumer and other high-volume areas did not see the need for such qualification and traceability tasks, and they were deemed to be cost-prohibitive. At IS IT OK TO Be HuMAn? continuesv Qualification consists first of all on fully documented and planned procedures, materials, and operational practice. All possibility of variation is removed, eliminating all possible sources of variation and human error. " "