Case Study 2-7
IET developed an assembly process and final inspection system for an automotive manufacturer that completed production in less than an hour with 100% reliability.
A tier one automotive interiors supplier requiring a production system for door interiors – delivering up to 900 door sets a day.
All deliveries had to be completed in sequence and within a three-hour timeframe from the assembly plant. Truck loading, transportation and line delivery were approximately two hours. Therefore, assembly and packaging had to be completed in less than one hour.
The production launch schedule (ramp up) was six weeks and over 2,000 finished part numbers were possible. Key processes included injection molding, die-punching, roto-casting, foaming, painting and assembly. The sequential build mandate combined with the three-hour production broadcast required the majority of the value-added activity to be performed after the order was received.
IET engineers designed four sequential build assembly lines that each produced one of a vehicle’s four doors every minute. The total value-added time in the assembly process was approximately sixteen minutes per door.
The production philosophy was driven by simplicity in the production flow, consistent and visible material flow, kanban material replenishment, and error proof (poka-yoke) assembly lines.
Major components feeding the assembly lines were staged with varied inventory levels based on forecasted mix, process capability and change-over times.
IET’s system resulted in an assembly process and final inspection system that was 100% reliable. Minor rework was completed in-process with no adjustment required to the final delivery container. Assembly labor utilization was maintained at about 90% and could be adjusted quickly for volume fluctuations.