Abstract:
This research aims to increase production efficiency of link power steering assembly line. The Toyota production system concept was applied to reduce several types of waste occurring in the assembly line. According to work study and analysis, the major causes of wasting time were repeated inspection of an automatic inspection machine, model change, and checking and repairing of leaking inspection machine. Excessive use of operators in the line also causes the line efficiency lower than the company target. This research was conducted to improve the waste that occurs. Air pressure generator of the automatic inspection machine was replaced to generate sufficient and stable pressure to eliminate incomplete inspection. Jigs used when changing production model were relocated to the position that easy for the operator to work with. Air pressure pumps of the leaking inspection machine were moved out of production operator working path. Then, the assembly line balancing was applied to reduce the number of operators in order that the lead times of each working station closed to the takt time. This requires eliminating unnecessary tasks, combining tasks, rearranging some assembly sequences, and simplifying some tasks by using equipment instead of workforce. The results of this research revealed that the production efficiency increased from 85.19% to 95.6% which achieved the company target. Productivity improved from 4.93 pieces per man-hour to 7.44 pieces per man-hour. The labor cost was reduced 600,000 baths per year, approximately.