Overview: Due to previous success of merging a green belt project with a Value Stream effort, Jay Zimmerman (New Product Development Engineer, Gast) was challenged to achieve a similar result for his green belt certification project within Gast’s second Value Stream. The success of the Air Motor Value Stream depended on better paint adhesion to reduce the disruption of manufacturing flow that reworking paint caused. His initial inquiries into possible alternative coatings brought UV (Ultra Violet) paint to the forefront of discussion. Its remarkable ability to cure very rapidly, as well as its phenomenal hardness and adhesion immediately drew attention to UV paint as a possible solution. Subsequently, and with the help of Dan Apotheker (Manufacturing Engineer, Gast) and Dave Kooienga (Thierica Equipment company), a design and layout were drawn up to coincide with the testing and other validations that were being performed. After the initial design stage and actual implementation, it was found that the new process saved 850 square feet and reduced the production lead time from 4.5 hours to less than 15 minutes. In addition, WIP (Work In Process) was reduced from 190 to 12 pcs, an amazing 94%! The Science of UV Paint, in brief UV paint can best be thought of as liquid plastic. This liquid will never evaporate, and will never harden under normal conditions; but when it is subjected to intense UV light, molecules of liquid bond with other molecules to form very, very long chains. The end result is a very hard, durable and chemically resistant coating known as polyester acrylate. This transition can happen in less than 2 seconds on flat surfaces, at the optimal distance from the light source. At Gast, the shape of an air motor prevented such a quick cure time.
During the “Analyze Phase” of the green belt project, the engineers experimented with several options and concluded that rotating the part in front of a UV bulb for 30 seconds would insure proper curing, and allow the cell to produce one painted and cured unit every 75 seconds; well below the required TAKT time of 90 seconds. Benefits and Drawbacks: The primary benefit of the new system is the reduction of lead time. Within the first two weeks of implementation a customer needed an expedited order of 50 air motors --- they sent a courier to pick them up only three hours after the raw material came to receiving. This would have never been possible with traditional paints. Other benefits include the dramatic reduction of Volatile Organic Compounds (VOCs). The VOC emissions into the environment from the Air Motor Value Stream were reduced to negligible amounts, along with the complete elimination of the noxious solvent MEK, a definite step in the right direction regarding the health of employees. Since implementation on August 14, 2006, even the employees of the Air Motor Value Stream have been impressed with the change. Jay and Dan have frequently heard comments that the air motors “look better,” and “won’t scratch or stick to packaging anymore.” Key Takeaways: The debugging phase of the Air Motor Value Stream is winding down, and the Value Stream implementation could not have been a success without the help of green belt projects like UV Paint. As a result of this synergy, customers will see the increased durability in the product and the increased responsiveness of Gast to emergency orders. Internally, Gast sees a reduction in WIP, and a substantial reduction in value stream process time.