Failure mode and effects analysis for maize drying process improvement

Abstract

This research aims to improve the efficiency and productivity (in terms of reduction in energy and fuel cost, drying time, and quantity of products rejected by QC) of a case studied factory whose main business is involved with the maize drying process. The scope of the research focuses on drying and furnace workstation units since these two units acquire the greatest energy and fuel cost compared to other units in the factory. The author has used the Failure Mode and Effects Analysis (FMEA), and Cause and Effect Diagram for identifying and analyzing the potential failure modes and their effects in a systematic way for both drying and furnace workstation units. Based on the study it was found that there were 19 high-risk areas that had RPN (Risk Priority Number) scores higher than 100 and they had to be addressed. These failures cause inefficient use of energy and low productivity in terms of high fuel and energy cost, long drying time and large amount of products rejected by QC. The results of analysis by means of using the Cause and Effect Diagram and FMEA technique have led to several improvements in the drying and furnace processes. These include generation of work instructions and preventive maintenance plan, modifying existing system, and establishing training programs. The results of implementation were the improvement in efficiency of energy use and productivity. The average fuel cost per month is reduced from 94.7 to 84.9 thousand baht and resulted in ability of increasing the temperature at 2 to 3 degree Celsius higher in drying rooms that caused the average drying time decreases from 7,150 to 6,580 minutes per batch. In addition, the RPN scores for all the 19 failures decreases in the range of 60.0-84.8%.