OVERALL EQUIPMENT EFFECTIVENESS (OEE) IMPROVEMENT ON PRODUCTION LINE OF FOOD PROCESSING INDUSTRY Tejus M 1, Dr.K.Chandrashekara 2 1,2

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1 OVERALL EQUIPMENT EFFECTIVENESS (OEE) IMPROVEMENT ON PRODUCTION LINE OF FOOD PROCESSING INDUSTRY Tejus M 1, Dr.K.Chandrashekara 2 1,2 Department of Mechanical Engineering, SJCE, Mysuru Abstract - Overall Equipment Effectiveness is an effective tool and a Key Performance Indicator (KPI) to improve the production performance of any organization. It considers various sub components of the manufacturing process like Availability, Performance and Quality. This study aims to improve the Overall Equipment Effectiveness (OEE) and to evaluate productivity. Improvement in OEE ensures the improvement in quality, availability and performance of the production line. Root cause analysis is carried out to analyse the root causes of production line faults. Keywords - Overall Equipment Effectiveness, Root cause analysis, Availability, Quality, Performance I. INTRODUCTION In food processing industry, production line is an important factor that decides the industry s fate in the competitive world to deliberate the fine food products into the market. Efficient production line enables the superior food processing within a short duration, if it is well maintained. However, the three parameters such as availability, performance of the machines and quality of the product are facing threats due to problems prone on production line. Because of improper maintenance of production line its availability has been decreased which in turn affecting the quality and performance. Since, these parameters contributes for OEE, it has drastically reduced. 1.1 Root Cause Analysis Root Cause Analysis is a method that is used to address a problem or non-conformance, in order to get to the "root cause" of the problem. It is used so that we can correct or eliminate the cause, and prevent the problem from recurring. RCA is simply an application of a series of well known, common sense techniques which can produce a systematic, quantified and documented approach to the identification, understanding and resolution of underlying causes. II. CASE STUDY The project work associated with the Overall Equipment Effectiveness (OEE) Improvement on Production Line of food processing industry. 2.1 Problem Identification The good food products were found to be rejected and sent to reworks, due to associated availability problem of production line which in turn affecting the overall performance of the production line. The conveyor belts of production line was found to be defective, that led the good food products to get rejected. 2.2 Observation Observation and scrutinizing the details of production line, good food products that are made to move over the guideways was found to be rejected. The conveyor belt length was less and led to decreased Overall Equipment Effectiveness which is not satisfying the requirement. Tabulation of readings are made by observing the production All Rights Reserved 368

2 Table 2.1 Data collection table Month Total Number of Production Total Number of Rejection February March April Total III. OEE CALCULATION FORMAT The following example is a 3 Shift of 8-hour with 2 scheduled 15 minute breaks for each shift and a 30 minute meal period for each shift. Table 3.1 Production data Production Data Shift Length 3 Shift 8 Hours = 1440 minutes Short Break 3 Shift 2 Break 15 Minutes = 90 minutes Meal Break 3 Shift 1 Break 30 Minutes = 90 minutes Ideal Run Rate Number of Products per minutes Support variables are calculated using the above information: Table 3.2 Support variables Support Variable Calculation Calculated Data Results Planned Production Time Shift Length-Breaks Operating Time Planned Production Time - Down Time Good Pieces Total number of products - Reject number of products The next table shows how the OEE percentage is calculated using the collected production data and calculated support variables Table 3.3 OEE calculations OEE Factor Calculation Calculated Data OEE % Availability Performance Quality Overall OEE Operating Time / Planned Production Time (Total number of products / Operating Time) / Ideal Run Rate Good number of products / Total number of products Availability x Performance x Quality Table 3.4 OEE calculation before modification Average Availability Quality Performance OEE OEE(Before modification) 94.5% 82.6% 93.5% All Rights Reserved 369

3 Average OEE before modification AVAILABILITY QUALITY PERFORMANCE OEE Figure 3.1 Average OEE calculation before modification key parameters viz. quality, availability and performance, by plotting charts for average value of all three parameters and OEE, it came to know that quality is the main parameter which affecting the OEE of production line. Quality is the percentage of good count of products produced per day out of the total number of products produced per day in production line. Good count of products produced per day Quality = Total number of products produced per day Total number of products produced per day Good count = Number of products rejected per day Quality of the production line is affected by the high number of product rejection in production line. 3.1 Root cause analysis of product conveyor belts The product conveyor belts PC5 and PC6 which are connected in between other belts PC3, PC4 and PC7 are subjected to root cause analysis to find the exact root causes of the problems associated on production line Problem description: The food products that are made to move over product conveyor belts PC5 and PC6 gets turned, hence it is causing rejection of the products. The non rejected over turned food products if passed through the belts PC7, then they get jammed and leads to breakdown. Table 3.5 Why Why analysis of product conveyor belts Why 1 Why 2 Why 3 Turning of food products Jumping of food products Small gap between conveyor belts PC5 and PC6 Why 4 Two conveyors are used PC5 and PC6 Root cause: Two conveyors are used Corrective action recommended: Replacing single belt instead of two All Rights Reserved 370

4 IV. MODIFICATION Figure 4.1 PC5 and PC6 before modifications PC5 Figure 4.2 PC5 and PC6 after modifications PC6 Figure 4.3 Line diagram after modification The product conveyor belts PC5 and PC6 were merged to form a single conveyor belt as shown in the Figure 4.3 line diagram, to avoid the jumping rejection problem of food products. Table 4.1 Data collection table after modification Month Total Number of Noodle Production Total Number of Noodle Rejection May June Total Table 4.2 OEE after modification Average Availability Performance Quality Overall OEE OEE(After modification) 94.63% 94.14% 95.95% 85.48% It is found that, the effect of modifications has reduced the associated problems of quality and thereby, there is an increase in the availability and the performance of production line. This pave the way to increase the Overall Equipment All Rights Reserved 371

5 V. RESULTS Comparison of OEE AVAILABILITY QUALITY PERFORMANCE OEE OEE(Before modification) OEE(After modification) Figure 5.1 Comparison of results before and after modifications The improved Overall Equipment Effectiveness (OEE) of production line has provided satisfactory availability and increased performance and superior quality products. VI. CONCLUSION The quality associated problems has been successfully resolved with decreased number of rejection of food products in the production line. The Overall Equipment Effectiveness (OEE) of the production line has been increased from 73% to 85.48%, that includes the satisfactory improvement in the parameters such as, availability from 94.5% to 94.63%, performance of the production line from 93.5% to 95.95% and quality from 82.6% to 94.14%. REFERENCES 1. Fabiana Pereira Castro, Fernando Oliveira de Araujo Proposal for OEE (Overall Equipment Effectiveness) Indicator Deployment in a Beverage Plant Brazilian Journal of Operations & Production Management Volume 9, Number 1, 2012, pp Wilson, P. F., Dell, L. D., & Anderson, G. F. (1993). Root Cause Analysis: A Tool for Total Quality Management. Milwaukee: ASQC Quality All Rights Reserved 372