Original Date: 06/26/1995
Revision Date: 01/18/2007

Dayton Parts, Inc. (DPI) established a purchasing task team in January 1993 to research the cost of purchased items and their related processes and determine if there were ways to reduce that cost. One significant example was the Signode process, which includes wrapping a band of steel with a rubber liner around spring leaves to keep them from spreading. DPI's Signode installation table dated to the 1930s, and frequently broke down; in addition, repair parts were hard to find. Therefore, the task team examined various hand-held banders, and also attempted to improve the Signode table, but neither presented a viable solution.

One team member noticed that clips on sample springs from other manufacturers looked different than the DPI clips. With the cooperation of another team at DPI, the purchasing task team developed new clips called Full Taper Clips. These clips could be used in many applications in place of the old Signode banding. After developing the clips, the team member from engineering -- with input from other members -- developed a machine to bend the clips during installation.

With the use of the clip bending machine, an air cylinder now presses the clip into place around the spring, rather than an assembly operator hammering the clip around the spring. This new process is faster and reduces the operator's risk of a repetitive motion injury from constant hammering. Initially this process was only used on full taper springs. However, it was so successful that DPI is now implementing the full taper clips on multi-leaf designs.

As a result of implementing the full taper clips, the use of the Signode machine has been drastically reduced. The machine has now been moved out of the main manufacturing area, leaving space for other operations. Also, the waiting time before the Signode process was eliminated, reducing throughput time by an average of three days per spring since full taper clips did not add material handling or waiting to the manufacturing process. The new clips are installed as part of the final assembly process. The risk of injury from repetitive motion and heavy lifting has been reduced. The product quality was increased which can provide a competitive advantage. And finally, product cost has been reduced. Although the material cost for the clips is higher than the bands, this cost is offset by reduced labor costs.

For more information see the Point of Contact for this survey.