Research Article Application of Reliability Centered Maintenance in a Bulb Manufacturing Unit Harmesh Kumar1, Rupinder Singh2, NS Bhangu3 Abstract In the present research work, application of Reliability Centered Maintenance (RCM) in a bulb manufacturing unit has been highlighted as a case study. Three lines of bulb assembly were running at a speed of 4250 bulbs/hour. Due to consistent low machine efficiency, there was an urgent requirement for analysis of the maintenance system. Last eight months data has been collected and analyzed for calculating the machine efficiency. The results of study suggested that as regards to down time in bulb manufacturing unit is concerned; sealing, mounting, threading machine, pump and stem contributes 27%, 23%, 15%, 10% and 7% respectively. The result of study proposed preventive maintenance plan with recommended actions. Keywords: Bulb Manufacturing, Breakdown Maintenance, Pareto Analysis, Reliability Centered Maintenance Introduction Over the past twenty years, maintenance has changed, perhaps more so than any other management discipline. The changes are due to a huge increase in the number and variety of physical assets (plant, equipment and buildings), which must be maintained throughout the world, much more complex designs, new maintenance techniques and changing views on maintenance organization and responsibilities. Maintenance is also responding to changing expectations. These include a rapidly growing awareness of the extent to which equipment failure affects safety and the environment, a growing awareness of the connection between maintenance and product quality and increasing pressure to achieve high plant availability and to contain costs.1 Maintenance people have to adopt completely new ways of thinking and acting, as engineers and as managers. In the face of this avalanche of change, managers everywhere are looking for a new approach to maintenance. They want to avoid the false starts and dead ends, which always accompany major upheavals. They seek a strategic framework, which synthesizes the new developments into a coherent pattern, so that they can evaluate them sensibly and apply those likely to be of most value to them and their companies.2,3 According to Moubray J if it is applied correctly, RCM transforms the relationships between the undertakings, which use it, their existing physical assets, and the people who operate and maintain those assets.7 Application of RCM in Bulb Manufacturing Unit: A Case Study For the present research work, a leading bulb manufacturing unit has been selected for the case study. In this manufacturing unit under study three lines of bulb manufacturing were running at a speed of 4250 bulbs/hour. The unit was engaged in manufacturing all types of fluorescent and incandescent bulbs along with in house manufacturing of coil and raw glass shell for tube lights. Department of Production Engineering, 3Department of Electrical Engineering, G. N. D. E College, Ludhiana-141006, Punjab, India. 1,2 Correspondence: Mr. Rupinder Singh, Department of Production Engineering, G. N. D. E College, Ludhiana-141006 (Punjab) India. E-mail Id: rupindersingh78@yahoo.com Orcid Id: http://orcid.org/0000-0001-8251-8943 How to cite this article: Kumar H, Singh R, Bhangu NS. Application of Reliability Centered Maintenance in a Bulb Manufacturing Unit. J Adv Res Qual Control Mgmt 2017; 2(3): 6-11. © ADR Journals 2017. All Rights Reserved. Kumar H et al. J. Adv. Res. Qual. Control Mgmt. 2017; 2(3) The machine efficiency of all the three lines was not up to the mark due to probable flaws and gaps in the maintenance system. Due to consistent low machine efficiency, it results into the increase in the cost of production and as a result of which company finds it difficult to meet the production targets. Therefore there was a requirement for analysis and up-gradation of the maintenance system, hence proposed to apply RCM in order to improve the machine efficiency and to optimize the maintenance system. The 2nd line was taken as pilot line for analysis of maintenance by using RCM methodology. • • The present work was carried out based upon MEDIC approach.4-6 A standard MEDIC format has been used for efficient problem solving. M: Map and Measure; E: Explore and Evaluate; D: Define and Describe; I: Implement and Improve; C: Control and Confirm. M- Phase Total Production Hours = 24 hrs/day Machine efficiency = [24 – (BM+PM)]/ [24] Objectives • RCM Implementation Approach Identification of the vital items which would contribute significantly in improving the machine efficiency To improve the machine efficiency of 2nd line by application of RCM Prepare preventive maintenance plan for 2nd line, based on RCM methodology Maintenance System In M phase, problems and various aspects related to these problems were measured and put on article. In order to identify type of problem, the last eight months data has been collected, analysed and presented by run charts (ref. Fig. 1-2) and Pareto charts (ref. Fig. 3-4). Figure 1.Run chart for machine efficiency Figure 2.Run chart for frequency of breakdown maintenance Explore and Evaluate Pareto analysis was performed to separate the “vital few” from the “trivial many” sources of failures. These charts are based on the Pareto principle, which states that 80% of the problems come from 20% of the causes. Figure 3.Pareto chart for line 7 J. Adv. Res. Qual. Control Mgmt. 2017; 2(3) Kumar H et al. Similarly Pareto charts for other machines, sections/sub sections have been made. After Pareto analysis the items were ranked based on their down time. RCM process has been applied on the significant items. The data collected of the significant items were filled in specially designed information worksheets (Table 1). Figure 4.Pareto chart for stem machine Table 1.RCM information worksheet: mount loader Function 1 To transfer mount from mount stock chain to sealing spindle at 4250 pieces/hr Function Failure (Loss of Function) A Cannot transfer at all B Transfer bulbs less than 4250pcs/hrs Failure Mode 1 Broken Mount Loader turning spring 2 Broken Jaw spring 3 Stuck Jaw opening shaft 4 Stuck up down shaft 1 Mount broken due to center out problem Failure Effects M/C will stop; downstream process will stop, will require 30 min to change spring by one mechanic and operator M/C will stop; downstream process will stop, will require 30 min to change spring by one mechanic and operator M/C will stop; downstream process will stop, will require 15 min to restore the condition by lubrication and cleaning M/C will stop; downstream process will stop, will require 20 min to restore the condition by lubrication and cleaning M/C will stop; downstream process will stop; will require 30min to center the assly. by highly skilled mechanic 8 Kumar H et al. J. Adv. Res. Qual. Control Mgmt. 2017; 2(3) 2 Timing out of up down and jaw opening cams 3 Assembly self alignment out 4 Worn out ball joint 5 Worn out bushes of up down shaft Assembly height disturbed 6 Develop and Describe The RCM decision logic scheme was used to evaluate the maintenance requirements for each significant item in terms of the failure consequences and selected only 9 M/C will stop; downstream process will stop; will required 60 min to match the timing again by 2 skilled mechanics M/C will stop; downstream process will stop; will require 30min by one mechanic to change the assembly. M/C will stop; downstream process will stop; will require 60 min. by one mechanic in order to change unit M/C will stop; will require 60 min. to change the bushes. M/C will stop; downstream process will stop; will require 30 min by 1 mechanic to set the height those which satisfied these requirements. The input to the decision logic scheme was RCM information worksheets of significant items and got output in the form of decision worksheets. The decision worksheets were prepared of the significant items based on the task selection tree (Table 2). J. Adv. Res. Qual. Control Mgmt. 2017; 2(3) Kumar H et al. Table 2.RCM decision worksheet: mount loader F FF FM E S E O 1I 2 O/ H 1 A 1 Y N N Y N Y 1 A 2 Y N N Y Y N 3 D N N Proposed Task Scheduled overhauling by changing spring; Discuss with supplier for consistent quality of springs; double spring may be provided; Check spring (failure finding) Scheduled overhauling by changing spring; Discuss with supplier for consistent quality of springs; double spring may be provided; Check spring (failure finding) No scheduled maint.; cleaning and lubrication by the operator; Guard may be provided so that dust and glass could not go inside No scheduled maintenance; cleaning and lubrication by the operator; Guard may be provided so that dust and glass could not go inside No scheduled maintenance; Up Down cam design can be improved; training to the fitter Safety is to be checked in every maintenance; Training to the fitter Safety is to be checked in every maintenance; Training to the operator Discard ball joint assy. 1 A 3 Y N N Y N N N 1 A 4 Y N N Y N N N 1 B 1 Y N N Y N N N 1 B 2 Y N N Y Y N N 1 B 3 Y N N Y Y N N 1 B 4 Y N N Y N N Y 1 B 5 Y N N Y N Y N Change bushes of up down shaft 1 B 6 Y N N Y N N N No Scheduled Maintenance; Training to the operator Initial Inter val 12w Can be done by Mech. Deptt. 2W 12w Mech. Deptt. 2W - VJ (Engine er) - VJ - VJ 2w Mech. Deptt. 2w Mech. Deptt. 24 weeks 16 weeks Mech. Deptt. Mech. Deptt. VJ Implement and Improve Preventive Maintenance Schedule: The preventive maintenance schedule was prepared based on the decision worksheets. 10 Kumar H et al. J. Adv. Res. Qual. Control Mgmt. 2017; 2(3) Table 3.Preventive Maintenance Schedule No. Machine Activity FREQ 1 2 MOUNT MOUNT 2W 4W 3 MOUNT 4 MOUNT 5 MOUNT 6 MOUNT Vacuum line cleaning Check and do main drive and all belts HEADS : -1) centering with jigs 2) main bushes to be changed Alignment of stem loader and mount unloader to be centered with jig on m/c with reference to head no 1 Coil drum vacuum valve plunger cleaning Vacuum sucker jaw cleaning and vacuum valve piston lubricate with oil Week no. 1 2 3 4 5 6 7 8 9 1 1 1 11 1 1 1 1 1 0 1 2 3 4 5 6 7 8 9 o o o o o o o o o o o 12W o 4W o o o 8W 4W o o o o o o o o o o o o o o o Conclusion References Reliability centered maintenance helps in improving the understanding of equipment failure and their impact on the machine performance. The following conclusion can be made from the present work: 1. Backlund F, Hanuu J. Can we make maintenance decision on risk analysis results? Journal of Quality in Maintenance Engineering 2002; 8(1): 77-91. 2. Clarke P, Young S. Reliability Centered Maintenance and HAZOP - is there a need of both? ASIEC 618822006 Hazard and Operability Studies, 2006. pp. 1-19. 3. Daya M. You may need RCM to enhance TPM implementation. Journal of Quality in Maintenance Engineering 2000; 6(2): 82-5. 4. Horton M. Optimum Maintenance and reliability centered maintenance. Maintenance 1993; 8(2): 8-13. 5. Knowles M. A systematic approach of managing risk. Reliability Centered Maintenance 1995; 10(1): 8-15. 6. Kumar H, Singh R, Mehta J. Application of reliability centered maintenance in bulb manufacturing unit. International Conference on Recent Developments in Mechanical Engineering, 2008. pp. 510-516. 7. Moubray J. Reliability Centred Maintenance. 2nd ed., Butterworth Heinemann Ltd, London, England. 1997. pp. 25-34. • • • 11 RCM methodology can be applied gainfully in bulb manufacturing unit The result of the study suggested that as regards to down time (in bulb manufacturing unit) Sealing, Mounting, Threading machine, Pump and Stem contributes 27%, 23%, 15%, 10% and 7% respectively. So, these machines should be critically examined for improving machine efficiency The proposed RCM plan would result in improving the efficiency of bulb manufacturing unit. Further the decision worksheets prepared for the vital items would be extremely useful for improving of maintenance system
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