Abstract:
This research aims to solve the breakage problem in the production of pp bands in the oven in the stretching process. The breakage problem causes waste a time in maintenance and loss of material and labor productivity, resulting in higher manufacturing costs from competitors. To solve the problem, this study applied the technique of FMEA (Failure Mode and Effects Analysis). The application of FMEA technique began with forming an FMEA team, which consisted of people from various departments. The team conducted brainstorming to identify all possible causes that could potentially lead to PP-band breakage problems with the aid of a detailed process flowchart and fishbone diagram. To analyze the real cause of breakage, a three-factor experiment was designed. After the cause of breakage is found, the corrective action is implemented to eliminate the problem. The finding from the experiment revealed that the real cause of the breakage of pp bands at the stretching oven was the bubbles which occurred in chilled water from chillers to quenching bath, which cooled down PP bands drawn from the extruder. Tiny bubble particles would combine to form big ones and touch the surface of pp bands in the bath. This causes abnormal surface of PP bands that can be easily broken during stretching process. After the problem of bubbles was solved, it was found that the breakage problem was eliminated. The results of this research help the case company reduce the material loss from breakage for approximately 265,000 baht a year even though this loss can be recycled. The company also gains benefit from increased productivity and reduced maintenance time. Furthermore, this research is used as a case study for the case company to apply the FMEA technique in other area to improve production. In addition, it suggests that the company should establish a preventive maintenance program because the bubbles which caused the breakage problem resulted from lack of proper preventive maintenance.
