Waste Reduction and Efficiency Enhancement in the Production Process

Case Study of Plastic Bag Factory

Abstract

This research presents methods for reducing waste and increasing efficiency in the production process. A case study of plastic bag factory in Bangkok is studied and it found that the plastic bag manufacturing process consists of 5 main processes; 1) raw material preparation process, 2) plastic pellet mixing process, 3) molding process, 4) blowing process, 5) cutting process, and 6) packing process. The problems encountered in the case study factory are several types of wastes generated in the production process, accounted for up to 8.525% of the monthly sales value. Only 92.14% of customer’s demand can be delivered during September to December, 2020. Four types of waste are found in the production process - forming improperly, sizing improperly, scattered jell spot, and seal tearing. Fishbone diagram is used as tools in analyzing the problems. It was found that the main causes of all problems were due to lack of working standards and manual, lack of standardization in quality inspection and control process, and poor quality of raw materials. The researcher has proposed solutions to the problems by establishing working standards and manuals in the molding process, blowing process, and cutting process. Raw material quality inspection and control guidelines is also established and presented to the factory. After implementing the proposed improvement guidelines, the average of wastes generating in the production process is reducing from 7.86% to 3.51%. This can be summarized that the purposed solutions can reduce waste, reduce production cost, and increasing the efficiency of the production process.