The assembly line operation within the factory of a major Auto Manufacturer was halting five to six times every day. After investigation, the Manufacturer concluded that non-conforming parts from the Supplier were causing the parts to be misaligned with a mating part during the assembly process.

When the Supplier was notified of the problem, they claimed that the parts being produced conformed completely to the required specifications. They even backed their claim by providing dimensional measurement documentation. Satisfied with the Supplier’s evidence, the Auto manufacturer carried out efforts to rebuild their assembly process in an attempt to correct the problem. However, after the rebuilding was completed, the assembly problems continued. The stoppages occurred at the same rate and there was no improvement in productivity.

The Auto Manufacturer called on Bobier to perform an independent dimensional measurement analysis on the Supplier’s parts, in order to verify that the parts were conforming, as the Supplier had convincingly demonstrated. The Auto Manufacturer gave Bobier 10 parts for dimensional measurement…Bobier found all of them to be non-conforming.

Bobier contacted the Supplier directly, on behalf of the Auto Manufacturer. The Supplier agreed to a study of the inspection procedure used to back their claims that the parts conformed to specifications. Bobier discovered that the Supplier was using an Inspection Fixture that actually “bent” the part during the inspection process in order to make it fit correctly – an inspection procedure not permissible in accordance to the recognized ANSI Y14.5 Standard. (This standard requires that a part of this type must conform to specification in a “free state” when being measured, with no force or bending applied.)

The Supplier then agreed to make $150,000 in adjustments to their tooling (adjustments that had been requested by the Auto Manufacturer when the problems were first recognized.) These manufacturing process changes corrected the “bend” in the parts, and the Supplier’s inspection procedure was also altered to inspect parts according to the required Standards and specifications. With correct, conforming parts now coming from the Supplier, assembly problems at the Auto Manufacturer’s plant disappeared.

Ultimately, the situation was resolved – but not before significant costs were paid. In addition to the accumulated production line downtime, the Auto Manufacturer had to replace defective parts that had left the factory – a cost of over $350,000. However, the greatest damage was less tangible: the loss of customer trust and satisfaction.