Cycle Time and Idle Time Reduction in an Engine Assembly Line by IJSTE

IJSTE - International Journal of Science Technology & Engineering | Volume 2 | Issue 05 | November 2015 ISSN (online): 2349-784X

Cycle Time and Idle Time Reduction in an Engine Assembly Line Amith J Prakash PG Scholar Department of Industrial Engineering & Management Mangalam college of Engineeering Ettumanoor

Aneesh K S Associate Professor Department of Mechanical Engineering Mangalam college of Engineeering Ettumanoor

Abstract This paper focuses on productivity improvement of a tiller assembly line by using operational analysis and assembly line balancing .The existing standard time in the assembly line is too old and inaccurate. A proposal of new standard time has been given to reduce the ineffective time. A heuristic method called Ranked Positional Weighted method is used for assembly line balancing. After the analysis of the existing time required for each tasks non value added time, value added time and production time has been found using stop watch time study. Micro motion study is done to find the ineffective time in each operation. Keywords: Idle Time, Standard Time Cycle Time, Line Balancing ________________________________________________________________________________________________________

I. INTRODUCTION An important problem faced in the production system is that of determining the time it takes to produce a unit of product, in order to thoroughly analyze the problem, the production process for each of product is analyzed. For every manufacturing organization, price of the product primarily compromises of manufacturing cost and desired profit. If a company wishes to increase its profit, one way is to reduce the manufacturing cost with maintaining the quality of the product. Waste reduction, especially the time waste, is an important factor to reduce the manufacturing cost.

II. NEED FOR LINE BALANCING In an Assembly Line if the workers are not utilized effectively then it results in less efficiency. If the Cycle Time of one work station is high them it will affect the production rate of the whole product, if the line balancing is done in the assembly line. It will result in smooth functioning of the plant without bottleneck. Here this paper focus to do Assembly Line Balancing by heuristic method Rank Position Weighted method (RPW)

III. LITERATURE SUMMARY Santosh T Ghutukade, Dr. Suresh M. Sawant, 2013 [1] explain a problem of line balancing in cashew nut shelling machine production using ranked position weighted method. The main purpose of this paper is to represent use of RPW method to develop the assembly line and balancing that line. With this study it is found that RPW method is useful when the less data is available. According to Vrittika Pachghar, R. S.Dalu March, (2014) [2] This paper presents the reviews of assembly line balancing methods and tries to find out latest developments and trends available in industries in order to minimize production time. This paper highlights the contributions of various assembly line balancing methods for global optimum solution and gaps in literature which discuss point have more attention from the study of assembly line balancing it is found that assembly lines are flow-line production systems, where a series of workstations, on which interchangeable parts are added to a product. Riyadh Mohammed Ali Hamza, Jassim Yousif Al-Manaa (2013) [3] In this paper A study imitating a procedure of a Two Stages Gear Box (2SGB) assembly line layout is presented. Three balancing methods are studied in which 2SGB is assembled. These methods are Rank position weight, larger candidate rate, and Column method. Mahbubur Rahman, Farjana Nur 2014 [4] explains that Waste reduction, especially the time waste, is an important factor to reduce manufacturing cost. Purpose of paper is to identify and address the ways to improve productivity and efficiency in domestic context. Line balancing job has been done by the help of Candidate rule and Ranked Positional Weight Technique. Line Balancing is an effective tool to suggest ways to reduce workstation number and increase the throughput of a manufacturing process. Satish Keru Raut 2014 [5] explains the time of producing a unit of product is directly proportional to the number of production stages involved and the time spent at eac h stage. Actual time of each operation is taken using time study and new times are proposed for improving productivity. This paper discusses the use of industrial engineering tools used for the purpose of productivity improvement. Sandip K. Kumbhar, Niranjan M. R [2014] [6] this paper is focusing on optimization of cycle time, reduction non value added work (3m-muda, muri, mura), kaizen. In this paper focus given on the optimization of cycle time and reduction of non-value added activity. Improvement in the productivity achieved and elimination of non value added activities has been done. The cost of operation is reduced considerably.

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Cycle Time and Idle Time Reduction in an Engine Assembly Line (IJSTE/ Volume 2 / Issue 05 / 027)

Patange Vidyut Chandra, [2013] [7] this paper focuses on the crucial area of productivity improvement with the use of work study technique mixed with modern soft skills. Knowing what is unnecessary is important than knowing what is the most important in production and operation. Based on those, we can eliminate insignificant tasks and non-productive activities. Management needs to understand its application not just from angle of Production improvement or finance improvement or resource utilization, but also should address critically the soft side of workers psychology to give the best to not only for accepting the productivity solutions, but also be a part on fore front during actual implementation to make the study really worth its time and effort. Prathamesh P Kulkarni [2014] [8] the objective of this paper is to present an overview on a new combined methodology for the efficient improvement in productivity with the help of various Work Study Methods associated with Lean Manufacturing Principles & Tools. S.H Eryuruk [2008] [9] explains two heuristic assembly line balancing techniques known as the “Ranked Positional Weight Technique”, and the “Probabilistic Line Balancing Technique”, were applied to solve the problem of multi-model assembly line balancing in a clothing company for two models. The aim of this article is the comparison of the efficiencies of two different procedures applied for the first time to solve line balancing in a clothing company. S.A. Oke [2006] [10] The study’s most important finding is that the time of producing a unit of product is directly proportional to the number of production stages involved and the time spent at each stage. In this paper, the time study concept in a production process is modeled mathematically

IV. PROBLEM IDENTIFICATION AND PROBLEM STATEMENT The After observation and analyzing production department the production rate of Power Tiller is reducing yearly, and not able to meet the required demand. The following are the main problems observed which cause this. 1) Idle times occurring in the assembly line is not controlled 2) The existing time standards are too old and inaccurate in present practices 3) The cycle time is not reduced in the assembly line  Problem Statement - “Excessive cycle time and uncontrolled idle time increases waste of time and reduce the productivity of a firm”

V. PROBLEM DEFINITION The production department consists of three Assembly sections. Transmission Assembly section, Engine assembly section and KMB-series section. The main problem of firm is the inability to meet the current demand of Power tillers. Production and demand details for the past three years are shown in the table below. Table - 1 Production and Demand details for past three years YEAR DEMAND PRODUCTION 2012 9800 7200 2013 8200 5700 2014 7500 5525 2015 (TILL AUG) 4500 2400

When the Production and demand for the past few years was analyzed, it is clear that the production is showing a down trend and not able to meet the demand. The table II shows the present Basic time of each section in the existing plant. Table - 2 Time taken of sub-assemblies for Transmission assembly in 2 shifts Day No: of sub Shift 1 Shift 2 Total Time assembly (hr) (min Day 1 10 4:30 4.41 9:11 551 Day 2 10 4:35 4.38 9:13 553 Day 3 8 4:25 4.45 9:10 550 Day 4 10 4:40 4.35 9:15 555 Day 5 8 4:38 4.30 9:08 548 Total 46 22:48 23:09 45:57 2757 Average 9.2 9:114 551.4

Basic time = Average actual time/Average no: of sub-assemblies completed =570/19.2 =29.68 min for one sub assembly Table - 3 Time taken for sub-assemblies for KMB series in 2 shifts No: of sub Total Time Day Shift 1 Shift 2 assembly (hr) (min Day 1 23 4:42 4:47 9:39 579 Day 2 25 4:35 4:32 9:07 547 Day 3 22 4:44 4:55 9:39 579 Day 4 20 4:50 4:43 9:33 573

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Cycle Time and Idle Time Reduction in an Engine Assembly Line (IJSTE/ Volume 2 / Issue 05 / 027)

Day 5 Total

25 115

Average

4:32 23:23

4:36 23:33

9:08 46:56

548 2816

9:23

563.2

Basic time = Average actual time/Average no: of part Assemblies completed =563.2/23 = 24.48 min for one sub assembly Table - 4 Time taken for sub-assemblies in Engine Assembly line No: of sub Total Time Day Shift 1 Shift 2 assembly (hr) (min Day 1 10 4:30 4.41 9:11 551 Day 2 10 4:35 4.38 9:13 553 Day 3 8 4:25 4.45 9:10 550 Day 4 10 4:40 4.35 9:15 555 Day 5 8 4:38 4.30 9:08 548 Total 46 22:48 23:09 45:57 2757 Average 19.2 9:114 551.4

Basic time = Average actual time/Average no: of part assemblies completed =551.4/9.2 =59.93 min for one sub assembly After calculation of overall basic time of the three sections in assembly line it is clear that the bottleneck is occurring in the Engine Assembly line. If the cycle time, idle time is reduced and the standard time is modified in these sections then the productivity can be improved. Sl No

Table - 5 Idle Time Occurring in Engine Assembly Line and precautions suggested Idle Time Category Precautions

1 2

Repair/Breakdown Of Equipment No Tools

Preventive Maintenance Arrange Spare Tools As Reserve

3 4

No Job Waiting For Assistant

Keep Sufficient Jobs For Work Immediate Assistance Should Be Arranged

5 6

Waiting Crane/Handling Equipment Waiting For Inspection

Effective Utilization Without Delay Prompt Inspection At Right Time

7 8

Machine Cleaning Accident Injury

Clean In Non-Working Time Safety Precautions, Good Housekeeping

9 10

Power Failure Official Permission

Arrange Generator Facility Give Prompt Permission If Relevant

Personal Permission

Give Prompt Permission If Relevant

VI. PROCEDURE A. Stage 1 In this stage the existing Assembly Line is studied to know whether it is efficient or not. Observation method and stop watch time study is used to check overall time of each section. In this stage the idle time is also noted. The existing process sheet is analyzed to find the area to be improved. Operation analysis is done in the present engine assembly line in order to find the NonValue added time, Value added time and production time which will help to reduce the wastage of time. B. Stage 2 In this stage the standard time for E1, E2 and ET found by giving a rating factor of 6% of which 3% is skill and effort rating factor and 3% is performance rating factor, and an Allowance of 10% is given of which 6% is personal allowance and 4% is fatigue allowance. Standard time calculation in ET has shown in the table below.

SL NO 1 2 3

Table â&#x20AC;&#x201C; 7 Standard time calculation of Engine testing (ET) BASIC FATIGUE PRESENT RATING TASK TIME ALLOWANCE TIME FACTOR (MIN) (4%) MOUNT ENGINE ON TEST BED 4.5 1.06 4.77 0.1908 CONNECT FUEL LINE TO DIESEL 3 1.06 3.18 0.1272 FILTER AND BLEED FILL WATER IN RADIATOR 2.5 1.06 2.65 0.106

PERSONAL ALLOWANCE (6%) 0.2862

STD TIME 5.247

0.1908

3.498

0.159

2.915

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Cycle Time and Idle Time Reduction in an Engine Assembly Line (IJSTE/ Volume 2 / Issue 05 / 027)

4 5 6 7 8 9 10 11 12 13 14

COUPLE DYNAMOMETER TO ENGINE FLY WHEEL FIX BREAK SHOES AND WATER PIPES

1.06

4.24

0.1696

0.2544

4.664

3.5

1.06

3.71

0.1484

0.2226

4.081

START ENGINE FILL ENGINE TEST RECORD ON VERIFICATION LOAD ENGINE GRADUALLY IN STEP 2 AND RUN ENGINE

1.06

4.24

0.1696

0.2544

4.664

4.5

1.06

4.77

0.1908

0.2862

5.247

1.06

5.3

0.212

0.318

5.83

ADJUST LOAD,CORRESPONDING TO RPM,RECORD TIME AND FUEL CONSUMPTION

4.5

1.06

4.77

0.1908

0.2862

5.247

1.06

4.24

0.1696

0.2544

4.664

4.5

1.06

4.77

0.1908

0.2862

5.247

1.06

4.24

0.1696

0.2544

4.664

3.5

1.06

3.71

0.1484

0.2226

4.081

2.5

1.06

2.65

0.106

0.159

2.915

CALCULATE AND RECORD SPECIFIC FUEL CONSUMPTION LOAD THE ENGINE FOR MAXIMUM AND RECORD MAX HP INCASE OF VARIATION REPORT TO SUPERIORS FOR RECTIFICATION CHECK CYLINDER HEAD BOLT AND VALVE-CLEARANCE WRITE THE TAG ,CLOSE AIR CLEAANER FLANGE TIME FOR ONE ENGINE

54 min

63 min

C. Stage 3 1) Final Stage In this stage the assembly line balancing is done in E1 and E2 by the aid of a heuristic method Rank positional weighted method. The table below shows the balanced Assembly line E1with a reduced cycle time 38 minutes instead of 52 minutes in the existing case. Similarly the line balancing in E2 is also done

TASK NO:

2 3 4

7 Total

Table – 6 Balanced Assembly line in E1 TIME SUM OF TIME ELEMENT (Min) (Min) A 7 36 K 8 C 6 R 8 D 3 G 4 B 32 35 L 3 S 28 36 H 8 E 24 36 I 7 T 5 J 15 34 M 6 N 8 V 5 U 8 37 O 18 W 4 X 7 Y 16 38 P 7 F 7 Q 8 252

NO: OF WORKERS

1 1 1

1 7

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Cycle Time and Idle Time Reduction in an Engine Assembly Line (IJSTE/ Volume 2 / Issue 05 / 027)

SECTION E1 E2 ET TOTAL

Table â&#x20AC;&#x201C; 8 Present Vs Proposed standard time STADARD NON VALUE PRESENT TIME TIME PROPOSED ADDED TIME 158.6 58.8 12 158.6 62.2 13 63 54 14 392.2 191.14 39

VII. RESULT The existing system was analyzed using Method Study and Time Study. Found that there is bottleneck in E1 and E2 engine assembly sections. In order to avoid that standard time has been proposed along with operational analysis and Line balancing is done in the E1, E2 assembly sections which ultimately helps to improve productivity

VIII. CONCLUSION Detailed study in the existing assembly line shows that the engine assembly line should improve in order to achieve yearly demand. So time standards are proposed and it can be used to reduce cycle time in the current assembly line. The idle times occurring in the assembly line also need to control with the suggested precautions. Cycle time of E1 and E2 is reduced so as to meet the yearly demand. The study shows that Engine Testing (ET) and Engine finishing (EF) need not modify. And the bottleneck is occurring in Engine section one (E1) and section two (E2)

REFERENCES [1]

Santosh T Ghutukade, Dr. Suresh M. Sawant, The use of Ranked Position weighted Method for Assembly Line Balancing, Ghutukade, International Journal of Advanced Engineering Research and Studies E-ISSN 2249â&#x20AC;&#x201C;8974, Int. J. Adv. Engg. Res. Studies / II/ IV/July-Sept., 2013/01-03 [2] Vrittika Pachghar, R. S. Dalu The Review of assembly line balancing methods, International Journal of Science and Research (IJSR) March, ISSN (Online): 2319-7064,Volume 3 Issue 3, March , (2014) [3] Riyadh Mohammed Ali Hamza, Jassim Yousif Al-Manaa, A study imitating a Procedure Of A Two Stages Gear Box (2SGB) Assembly Line, Global Perspectives On Engineering Management, Vol.2, Issue 2,pp.70-81(2013) [4] Mahbubur Rahman, Farjana Nur An Integrated Framework of Applying Line Balancing In Apparel Manufacturing Organization: A Case Study, Journal of Mechanical Engineering, Vol ME 44, NO. 2, DECEMBER 2014 [5] Satish Keru Raut, A Case Study of Productivity Improvement by using IE Tools, International Journal Of Innovations in Engineering Research and Technology Volume 1, Issue 1 November, [2014] [6] Sandip K Khumbhar, Niranjan M R, Sanjay T Satpute, Assembly Line production improvement by optimization of cycle time, Proceedings of 10th IRF International Conference, 1st June, [2014] [7] Patange Vidyut Chandra, An Effort to Apply Work And Time Study Techniques in a Manufacturing Unit for Enhancing Productivity, International a Journal of Innovative Research in Science, Engineering And Technology, Vol. 2, Issue 8, August [2013] [8] Prathamesh P Kulkarni, Sagar S Kshire, Kailas V Chandratre, Productivity Improvement Through Lean Deployememnt And Work Study Methods, International Journal Of Research And Technology, Feb[2014] [9] S.H Eryuruk, S. H Eryuruk, A Research On The Effect Of Method Study On Production Volume And Assembly Line Efficiency, [2014] [10] S A Oke [2006] S A Oke, A Case Study Application of Time Study Model in an Aluminium Company, The Pacific Journal Of Science and Technology, Vol 7 Number 2, November [2006]

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