Breakdown Analysis and Performance Improvement of Powder Packing Machine

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1 Breakdown Analysis and Performance Improvement of Powder Packing Machine Vikas BM 1, Dr. M S Prabhuswamy 2 1 Department of Mechanical Engineering, SJCE Mysuru 2 Department of Mechanical Engineering, SJCE Mysuru Abstract: The main aim of this dissertation work is to analyze the breakdown problems and to improve the performance of powder packing machine. The detailed breakdown analysis of packing machine is discussed with the help of Root Cause Analysis (RCA) and Why Why Analysis tool to find the exact root causes of the problems. The corrective actions are suggested to eliminate the causes of non conformities. The effect of implementation of modifications; minimized the breakdown time, with higher production rate, increased availability and which in turn undoubtedly increased the performance of the machine. Keywords: Root cause analysis, Why Why Analysis, Performance, Availability, Production rate. I. INTRODUCTION The powder packing machine, is ultra fast machine, capable of packing nearly 720 packs in a minute. However, due to associated breakdown problems, the performance of the machine has reduced making the machine unavailable for use. The powder is made to pour from hopper to agitator drum. Agitators mixes the powder in clockwise direction. This makes the powder to fill into the chutes through the holes of the drum. Chutes are cup shape funnels that is wounded by aluminium foil called laminate to make packs. Powder is filled into these packs made by chutes which rotates in anticlockwise direction on chute rollers. The packets made, are sealed by pre heaters and are then dragged to storage polymer bins. Packing machine is fully automatic and consumes 6 kw of power. The breakdowns of critical parts like chute rollers that rolls over guideways and covering plates of chutes to cover the filled packets are analyzed for the root causes. With the implementation of effective modifications to these critical parts pave the way to eliminate the breakdown problems and thus improve the performance of the machine with its availability. 1.1 Breakdown problems statement 1) Lubrication outlet in the machine is absent, inlet itself acts as outlet. However, it is not effective. Lubricants fed, gets accumulated over the guideways. Whenever the chute rollers that rolls over the guideways of machine, they slides, clogged and gets jammed, obstructing the rotation of chutes leading to breakdown. 2) Covering plates present between agitator drum and chutes, have more thickness than the clearance provided. It obstructs the easy rotation of chutes due to friction developed and thus, gets blocked in between chutes and agitator drum causing breakdown. 1.2 Objectives 1) To provide the lubrication channel for the packing machine 2) To reduce the thickness of covering plates 3) To improve the performance of the machine and its All Rights Reserved 483

2 Holes of Agitator Drum Chute Problem Area Covering Plates Problem Area Chute Rollers Figure 1. Problem area of powder packing machine II. BREAKDOWN ANALYSIS 2.1 Root cause analysis It is a method to identify the behavior of the failure and its root causes in a systematic way. It comprises why-why analysis tree to reveal the actual root causes of the failure. 2.2 Why Why analysis It is a method to inspect and to identify the problems through series of whys. It understands the problem by asking why it should happen in that way. 2.3 Problem 1 Rollers of chutes gets jams over guideways Why rollers gets jam over guideways and does not support easy movement of the chutes? Why lubricant spills over guideways? Why there is no lubrication outlet given? Why the removal of used lubricant is not efficient? Table 2.1 Why-why analysis of chute rollers Lubricant spills over guideways. Rollers slides over it, and obstructs the rotating motion of the chutes. Lubrication outlet is absent Lubrication inlet itself acts as outlet too. However, it s not so efficient in removing complete lubricant from chamber. Sucking pressure for removing lubricant is less than, pumping pressure of lubricant inside. Also, while removing lubricant, it might contain other particles that cling to outlet port causing obstruction for easy removal Corrective action Providing proper lubrication channel and suction generator to remove the stains of the left over All Rights Reserved 484

3 2.4 Problem 2 Covering plates gets jammed between chutes and agitator drum Table 2.2 Why-why analysis of covering plates of chutes Why covering plates gets jammed between chutes and drum? Why covering plates catches more frictional heat? Why there is a minimum clearance between chutes and drum? Why does the powder get adhere? Due to frictional heat developed The thickness of the plates is more, while the clearance between chutes and agitator drum is less. Minimum clearance is provided to avoid influence of powder between the gaps and to avoid its adhering Since it is powder, it can easily fill the gaps. However, the moisture content in the powder is quite more Corrective action Reduce the thickness of the covering plates and smoothen its surface, also ensure the optimal clearance between chutes and agitator drum. 2.5 Breakdown data Table 2.3 Average breakdown data of packing machine for quarterly period Avg. Avg. No. of Avg. Avg. Avg. Avg. Breakdown Breakdowns RPM TSR RVSR LVSR Time in Occurred hours Total RPM Revolutions per Minute TSR Top Sealer Reading RVSR Right Vertical Sealer Reading LVSR Left Vertical Sealer All Rights Reserved 485

4 Performance and Availability Performance and Availability of Machine Before Modifications 83.44% 90.00% 78.38% 76.50% 79.85% 74.60% 75.28% 73.33% 76.71% 80.00% 67.81% 70.00% 57.85% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% JAN FEB MARCH APRIL MAY Performance of Machine 78.38% 74.60% 83.44% 73.33% 57.85% Availability of Machine 67.81% 76.50% 75.28% 79.85% 76.71% MONTHS Performance of Machine Availability of Machine Figure 2.1 Performance and availability of machine for quarterly period before modification Overall Results of Parameters During Machine is under Breakdown 76.22% 85.14% % 51% 80.00% 60.00% 40.00% 20.00% 0.00% Results Before Modifications Performance 76.22% Availability 85.14% Production Rate 51% Performance Availability Production Rate Figure 2.2 Overall average results of performance and availability of machine for quarterly All Rights Reserved 486

5 3.1 Modification 1 III. MODIFICATIONS Figure 3.1 Lubrication channel before modification Figure 3.2 Lubrication channel after modification with suction generator The lubrication channel has modified with the provision of suction generator that completely drains of the left over lubricant present on the guideways. The above figures clearly differentiates the modification. This eliminated the breakdown problem of jamming of chute rollers over the guideways, when they slides and gets clogged with each other. The suction pressure that is build up by the generator is enough to remove the stains of lubricant. It varies depending upon the quantity of lubricant being deposited over All Rights Reserved 487

6 3.2 Modification 2 Before Modification After Modification Thickness reduced Figure 3.3 Covering plates before and after modification The covering plate s thickness was reduced from 1.2mm to 0.9mm using trial and error method and its thickness is measured using vernier calipers instrument. The above figure depicts the modification. It shows, soon after the modification, the covering plate perfectly placed in between agitator drum and chutes providing optimal clearance. Whereas, initially it is placed forcibly indicating that it obstructed the rotation of the chutes. The arrow indicates the anticlockwise rotation of chutes. The above modification reduced the covering plate breakdown problem and thus lead the path to improve the overall performance of the machine undoubtedly ensuring its availability. The machine soon after modification was kept under observation and been tested for desired results. IV. RESULTS AFTER MODIFICATION Overall Results of Parameters of Machine After Modifications % 95.00% 90.00% 90.62% 85.00% Results After Modifications Performance 90.62% Availability 99.72% Production Rate 100% 99.72% 100% Performance Availability Production Rate Figure 4.1 Results after All Rights Reserved 488

7 Comparison of Results Before and After Modifications % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% 76.22% 90.62% 85.14% 99.72% % 51% PERFORMANC AVAILABILIT E Y Before Modification 76.22% 85.14% 51% PRODUCTION RATE After Modification 90.62% 99.72% % Before Modification After Modification Figure 4.2 Comparison of results before and after modifications V. CONCLUSION 1. The breakdown problems associated with the packing machine is reduced. Thus, the chance of risk of failures has decreased. The effective modifications discussed, is successfully incorporated which eliminated the possible causes of failure which are recurrence in nature. 2. Thus, there is an increase in performance of the machine from 76.22% to 90.62% which has reasonably adds to improvement in the availability of the machine from 85.14% to 99.72%. 3. Additionally, increase in performance of the machine, has undoubtedly increased the production rate. REFERENCES 1. Prof. Duggett Packaging Industrial Topack Automation & Monitoring failures by Root Cause Analysis, Page 01 04, September Clarie.John, Preventive and Breakdown Analysis, of Packing Machine Using Programmable Logic Controller ISSN (Print): , Volume 01, Issue 02, Bamber, Pouch Maker and Packing Machine International Journal of Multidisciplinary Sciences and Engineering, Volume 2, Issue 08, November All Rights Reserved 489