International Journal of Applied Engineering Research, ISSN 0973-4562 Vol. 10 No.61 (2015) © Research India Publications; httpwww.ripublication.comijaer.htm
Implementation of Lean concept and performance analysis of manufacturing system using simulation: A case study Moshim G. Mulla, Asst. Prof. Mechanical Engg Dept MBT Campus, Islampur, India
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Ansar A. Mulla, Asst. Prof. Mechanical Engg Dept MBT Campus, Islampur, India
[email protected]
MukundKavade, Assoc. Prof. Mechanical Engg Dept RIT Islampur, India.
Mahesh Latte Asst. Prof. Mechanical Engg Dept DYPCOE Kolhapur, India
[email protected]
SudhanvaDeshpande Senior Manager. Emerson Climate tech. Atit, India
,
Abstract— To days industries striving hard to find methods for low cost, high production in laser time. Lean manufacturing concepts are used by industries to reduce various wastes in manufacturing for competing the global market. This research work has been carried out as a case study at Emerson Climate Technologies (ETC) India Ltd. plant located at Atit with an objective of waste reduction. Effort is made to reduce motion waste in the shop floor by work combination technique. Research work shows house of the simple lean concept and advance simulation software in industry for eliminates non value added activities and operational wastes. Problems in current production line are identified, and analyzed with the help of WITNESS simulation software. Then the layout is modified, simulated and results are compared with current layout. The results show that one operator is elevated than the previous. It saves in operator’s salary, which is considerable saving in total revenue. Proposed layout successfully implemented in industry and results are validated. Keywords- Lean Manufacturing, WITNESS Software.
line is taken for study. Because this line shows measurable motion waste in time study date and there is measurable improvement by small changes in layout. There are various techniques available to improve the productivity and increasing the revenue of the plant. Reduction of the small wastages during the manufacturing the products is one of them. Waste reduction method is same as continuous improvement. In following section we observed that how lean concepts (reduction of motion waste) increases productivity and revenue of the plant. II. METHODOLOGY
I. INTRODUCTION Productivity is a measure of the rate at which outputs of goods and services are produced per unit of input (labor, capital, raw materials, etc.). It is calculated as the ratio of the amount of outputs produced to some measure of the amount of inputs used. Productivity measures are used at the level of firms, industries and entire economies. Depending on the context and the selection of input and output measures, productivity calculations can have different interpretations. Improving productivity can have connotations of economizing on the use of inputs for example, adopting efficient production processes that minimize waste. Equally, improving productivity can have connotations of yielding more output for example, using resources in activities or with technologies that generate more output. Moore, a very well known name in the business world, explained plant layout as, “The plan of or the act of planning, an optimum arrangement of facilities, including personnel, operating equipment, storage space, materials handling equipment and all other supporting services along with the design of the best structure to accommodate these facilities”. In this research work compressor body machinating
Fig 01: Block diagram of methodology followed in this case study
Abbreviations Opn – Operation
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International Journal of Applied Engineering Research, ISSN 0973-4562 Vol. 10 No.61 (2015) © Research India Publications; httpwww.ripublication.comijaer.htm
SPM-Special purpose machine CNC – Computerized numrical centre M/C – Machine Sr.No. – Serial Number No. - Number III Current Compressor Body machine line
A case study on machining of compressor body also known as compressor crank case has been chosen to find the working of current layout and its performance. The compressor body is machined using various machines like, CNC, special purpose and VMC, etc. The figure of compressor body is as shown below
Fine boring and milling
Honing
,
Tapping
De-burring
Bush press
Fig 02: Compressor Body or Crank Case
The part flow and sequence of the machining operations carried out on the compressor body from raw material to final finished good are as shown in figure. The machines used for the body finishing are Bush press machine, two CNC machines, two VMC machines, one Special purpose machine and one Honing machines. Opn No.
M/C type
No. of. Operator
No. of Components
Man working time in sec
Fig 03: Flow chart for Compressor Body finishing
Man idle time in sec
M/C working time in sec
M/C idle time in sec
Cycle time in sec
Cycle time per component in sec
24.2 90 90 0 0 0 0 10 10 10
20 480 480 70 70 70 20 80 20 0
24.2 60 60 0 20 20 0 0 0 0
44.2 540 540 70 90 90 20 80 20 30
44.2 270 270 70 45 45 20 40 10 15
1 Press 1 1 20 2 CNC 1 2 30 2 CNC 1 2 30 2 SPM 1 1 70 3 VMC 1 2 20 3 VMC 1 2 20 4 Deburr 1 10 20 5 Honing 1 2 30 6 Washing 2 2 30 7 Paking 2 2 20 The major issues seened in current layout are explained as follows and current layout is as depicted below figure
Current layout is drawn with the help of WITNESS simulation software. In this layout found that motion waste of the operators. Therefore there is scope for improvement by reducing idle time of the operators. Detail time study data is shown below table
Fig 04: Current layout in WITNESS 374
International Journal of Applied Engineering Research, ISSN 0973-4562 Vol. 10 No.61 (2015) © Research India Publications; httpwww.ripublication.comijaer.htm
operating time are feed in software. The simulation result are shown in table Table 03: Current machines Simulation result
Table2: Idle time for the operators for three shifts in one day Sr. Opn. Man idle Output Idle Idle time No No. time for s /day time for for . one cylcle 3 shifts operator/ in sec in one day in day in hours sec 1 1 24.2 166 4019 11.16 1 6 2 2 180 306 5508 15.3 0 Total 26.9 Above table shows measurable value of the idle time of operation number one and two. For operation number two there is three machines are employed. In that two mazak CNC machine and one is SPM machine. CNC machine cycle time is more than the SPM. With reference to above table there is more idle time for operators and this will be reducing by operating three machines simultaneously. Before modification in current layout simulation is carried out with help of WITNESS simulation software.
Table 04: Current Operator Simulation Result
IV SIMULATION OF CURRENT LAYOUT Current compressor body machining line modeling and simulation is done using WITNESS simulation software. For model creation some assumptions are made such as follows Sr. Assumptions No. Compressor semi finish bodies are always 1 available at the store-room. The Model is flexible and new elements can be . 2 easily add or remove. No stoppage occurs during the production in the . 3 model, In the model, no allowance is made for machine . 4 breakdown and repair time. . For parts, First-In-First-Out (FIFO) rule is applied. 5 . With above assumption, of the current production line is done in WITNESS software. A simulation run for 1836000 seconds (one month machine available time) snap shot of simulation is shown figure
Below figure shows the reports generated in witness simulation software. Reports shows Machine and Operator statistic reports in the form of graphs
Fig 06: Machine Statistic Report Cart-I
Fig 05: Simulation Snap Shot Input data regarding number of machines, it’s sequence, cycle time and setup time, number of operators its
Fig 07: Machine Statistic Report Cart-II 375
International Journal of Applied Engineering Research, ISSN 0973-4562 Vol. 10 No.61 (2015) © Research India Publications; httpwww.ripublication.comijaer.htm
press and two Mazak machines
VI SIMULATION OF NEW LAYOUT With the help of WITNESS software simulate the new layout. Input data are provided to software regarding number of activity activity, sequence, processing time and work combination condition also applied and simulation is done for one month time available i.e.1836000 seconds. Snap shot of simulation is shown figure
Fig 08: Operator Statistic Report Cart-I
Fig 09: Operator Statistic Report Cart-II
Fig 11: Proposed layout Simulation in WITNESS
From above WITNESS report shows that Idle time percentage for the Mazak machine operator is 60% and Busy time percentage is 40%. This is majar wastage, required to reduce this wastage by assigning additional machine to this operator, which is shown in new layout as follow.
Results obtained from this simulation are shown table Table 5: Proposed machines Simulation result
V PROPOSED LAYOUT Reducing the idle time of the operators modification done in current layout. Idle time for the operator on mazak machine is more therefore assign one addition machine to this operator, work as simultaneously with both mazak machines. For this arrangement orientation of Mazak machines and also places are changed to lesser the operator movement. And Mazak machine orientation also changes such that front faces of the machine are front of each other therefore reduces the motion waste of the operator. Modified layout is as shown figure
Table 6: Proposed operator Simulation result
Fig 10 : Proposed layout in WITNESS In new layout red circle shows the work combination. One operator operate simultaneously three machine first bush 376
International Journal of Applied Engineering Research, ISSN 0973-4562 Vol. 10 No.61 (2015) © Research India Publications; httpwww.ripublication.comijaer.htm
profitability of the industry by eliminate non value added activities and operational wastes. In this paper reduction in motion waste in shop floor i.e. operator idle time is reduced by assigning additional machine. Modeling and Simulation study is carried out for finding performance of the current layout in lean prospective and modification in current layout are made to elevate waste. By work combination there is one operator elevated in proposed layout than the previous. It saves 350 rupees per shift from the operator’s salary. Hence it saves Rs. 1, 27,750 per year which is considerable savings in total revenue. REFERENCES
A. Table - Operator Statistic Report-II Above results shows that in modified layout or by work combination operator busy time percentage are increases from 60% to 100%. Reports generated for this simulation are shown in below fig 07.
[1] M. T. Telsang, “Production Management” S. Chand, India,2012 [2] Richard Muther, Maynard’s Industrial EngineeringHandbook, fourth edition, McGraw- Hill, 1992 [3] N. G. Nair, “Production and Operations Management”TATA McGraw Hill, 1996 [4] Amine Drira, Henri Pierreval, Sonia Hajri-Gabouj, “Facilitylayout problems: A survey” Annual Reviews in Control 31(2007) 255–267 [5] Mohamed Essafi, Xavier Delorme, AlexandreDolgui“Balancing lines with CNC machines: A multi-start ant basedheuristic” CIRP Journal of Manufacturing Science andTechnology 2 (2010) 176–182 [6] N. V. Ruikar, M. T. Telsang, “Modeling and Simulation ofManufacturing Performances using WITNESS” IOSRJournal of Mechanical and Civil Engineering (IOSR-JMCE)ISSN (e): 2278-1684, ISSN (p): 2320–334X, 2012 PP: 11-17 [7] K. Hemanand , “Improving Productivity of ManufacturingDivision using Lean Concepts and Development of MaterialGravity Feeder – a case study” International Journal of LeanThinking vol.3 December 2012 [8] Jeffrey S. Smith, “Survey on the Use of Simulation forManufacturing System Design and Operation” Journal ofManufacturing Systems Vol.22/No.2 2003
Table 07: Machine Statistic Report-II Name
Before Work Combination
% Busy
60.00
After Work Combinati on 100.00
% Idle
40.00
00.00
Quantity
1
Improvem ents
Increase by 40% Reduce by 40%
1
VII CONCLUSIONS An attempt has been made to improve productivity and
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