Line Balancing In Garments Industry

Prepared By : Mazadul Hasan sheshirID: 201000040000813th Batch (session 2009-2013)Department : Wet Processing Technology Email: [email protected] : www. Textilelab.blogspot.com (visit)

Southeast University Department Of Textile Engineering

I/A 251,252 Tejgaon Dhaka Bangladesh

Prepared By :

Total Textile Process at a Glance

Introduction Line and work cell balancing is an effective tool to improve the throughput of assembly lines and work cells while reducing manpower requirements and costs. Assembly Line Balancing or simply Line Balancing (LB) is the problem of assigning operations to workstations along an assembly line, in such a way that the assignment be optimal in some sense. LB has been an optimization problem of significant industrial importance: the efficiency difference between an optimal and a sub-optimal assignment can yield economies (or waste) reaching millions of dollars per year. LB is a classic Operations Research (OR) optimization problem, having been tackled by OR over several decades. Many algorithms have been proposed for the problem. Yet despite the practical importance of the problem, and the OR efforts that have been made to tackle it, little commercially available software is available to help industry in optimizing their lines.

LINE BALANCING (Process Organization)

The Line Balancing is “to design a smooth production flow

by allotting processes to workers so as to allow each

worker to complete the allotted workload within an even

time” It is a system where we meet the production

expectations and we can find the same amount of work in

process in every operation at any point in the day.

Reasons to have balance the production line

(1) Keeping inventory costs low results in higher net income.

(2) Keeping normal inventory levels lets the operator work all day long giving him/her the opportunity to earn more money by increasing his/her efficiency.

(3)Keeping the line balanced let’s the supervisors improve other areas because they can use their time better.

(4) Balanced production keeps prices low which turns into repeat sales.

(5) Balanced production means better production planning.

Balancing Method

The most basic methods are the Time Study,

Bottle Neck Process Theory and Data Collection and

Analysis.

How do we start balancing the production line?

Well we can start by determining how many operators for each operation are needed for a determined level of production. After this we need to determine how much WIP we need to anticipate production problems. Recommended WIP is 1-hour inventory level for each operation. A good range would be from 30 min to 120 min inventory level.

There are 3 rules for balancing

(1) Have at least ½ hour of WIP for each operation

(2) Solve problems before they become any larger

(3) Meet production goals by keeping every operator working at their maximum capacity

Time Study

What is time study?

Time study is a work measurement technique for recording the time of performing a certain specific job or its element carried out under specific condition and for analyzing the data so as to obtain the time necessary for an operator to carry out at a defined rate of performance

Time study is a method of direct observation. A trained observer watches the job and records data as the job is being performed over a number of cycles.

Time study equipment

the stop watch in general, two types of watch are used for time study.

Fly back

Continuous

These watches may be used any of the following time scales

Seconds

Decimal minutes

Decimal hours

Time Study

SMV

SMV – time that is allowed to perform the job

satisfactory.

SMV = Basic time + Allowances

Standard Minute Value

SMV = B.T + Allowances

Basic Time

The basic time for the operation is found by applying concept of rating to relate the observed to that of a standard place of working.

Calculated as follows:

Basic time = observed time * observed rating

100 (BT = Observed time * Observed Rating= A

constant) 100

Example..

Rating 50 75 100 125

Observed time 1.2 0.8 0.6 0.5

Basic Time 1.2*50 0.8*75 0.6*100 0.5*125

100 100 100 100

= 0.6 0.6 0.6 0.6

SMV calculation

Element descriptionElement description Obser Obser ratingrating

Obser. Obser. timetime

Basic Basic TimeTime

Freq.Freq. Basic Basic Time/GmtTime/Gmt

Get bundle and sort partsGet bundle and sort parts 9595 0.320.32 0.3040.304 1/301/30 0.0100.010

Match pocket flap to liningMatch pocket flap to lining 105105 0.110.11 0.1160.116 1/11/1 0.1160.116

Sew round flapSew round flap 100100 0.480.48 0.4800.480 1/11/1 0.4800.480

Trim threads and turn out Trim threads and turn out flapflap

5858 0.350.35 0.2980.298 1/11/1 0.2980.298

Top stitch flapTop stitch flap 9090 0.560.56 0.5040.504 1/11/1 0.5040.504

Close bundle and place Close bundle and place asideaside

110110 0.230.23 0.2530.253 1/301/30 0.0080.008

TotalTotal 1.4161.416

Total basic time/garment (brought forward) 1.416

Add machine attention allowances 7%

7% of (0.480 + 0.504) = 0.07 x 0.984 = 0.069 0.069

Basic time + MAA (1.416 + 0.069) 1.485

Add personal needs and relaxation allowances 14%

14% of 1.485 = 0.14 x 1.485 = 0.208 0.028

Standard minute Value (SMV) = Basic time + all allowances

= 1.485 + 0.208 = 1.693 (SMV)

Production Planning

Load and capacity Planning

Successful planning requires knowledge of two variables to determine the time required to manufacture a contract.

Load – How much work we are putting on a section

Capacity – How much work a section is capable of completing

In an ideal situation

>> Load = Capacity

Load and capacity

LOAD – Contract size x Work content

Capacity – The amount of work the factory or section is capable of doing.

The scheduling rule

Balance load and capacity

Arrange the programmed of work so that the load can be achieved

Use common units – standard minutes

Balancing & CapacityLoad

Uncertainty about the number of garments to be sold Demand?

Speculation?

Prediction?

Uncertainty about work content

Standard minute value

Measured

Estimated

Capacity

Uncertainty about the number of operators and performance

Total numbers

Attendance hours

Absenteeism

Performance

Learning curve

Uncertainty about the equipment

Availability

Reliability

Pitch Time

Reference value for synchronization in the division of

labor is called Pitch Time (PT). Pitch Time provides

average time allotted to each worker.

Bottleneck Process:

The time at which the longest time is required is called “bottleneck Process” The state of line organization should be evaluated as “Organization Efficiency” Using the pitch time and Bottleneck Process Time.

Pitch Time

Organization Efficiency (%) = ________________________ x 100

Bottleneck Process Time

100

= ______ X 100

140

= 71.4 % (For the aforementioned case study)

Pitch Diagram in the form of Column Graph

160140

120

100

80

60

40

20Wor

k Allo

tmen

t Tim

e

A B C D E F G H

85115

801 0 5

110

7095

1 4 0

(Seconds)

Pitch Diagram (bar graph)

1st bottleneck Process Loss in balance

Loss in balance 2nd bottleneck Process

Name of worker (in the order of processes)

Work Allotment Time

How to reduce the number of bottleneck processes

(1) Investigate the relation between the bottleneck process and its previous and subsequent processes to correct the line organization.

(2) Investigate whether it is possible to further divide the process.

(3) Conduct the motion study for work improvement.

(4) Make improvements to equipment, jig and tools.

(5) Mechanize the manual work.

(6) Change the positions of workers.

(7) Investigate the modification to the machining specifications.

(8) Make it a rule to lend the worker in charge of the bottleneck process a helping hand

Control limit

(seconds)

160 Bottleneck Process

140

120Upper Limit

100

80 Lower Limit

60

40

20

A B C D E F G H

Name of worker (In order of processes)

Work

Allo

tment

Tim

e

8070

140

105115

140

110

140

105115

140 95

140

105115

140

110

95

140

105115

140

110

95

140

105115

140

70

110

95

140

105115

85

Control limit

Pitch Time Upper Limit = _________________________ X 100 Target organization efficiency = 0.85 = 117.6 Seconds

Lower Limit = 2 x Pitch Time – Upper Limit = 2 x 100 – 117.6 = 82.4 Seconds

Data Collection

One Composite Mills Ltd.Capacity check sheet U-1 (Line: 2)

Style no: 29694 Target: 180pcs/ hour Buyer: Collin’s Order quantity: 18694 Description: T-Shirt

Type: Basic

27-03-2013SL Operation Name Operator Name & ID M/C

typeActual output per hour

Process time (3pcs)

Avg. time with 20% allowance

1 Shoulder join-1 Roman 17371 O/L 138 22,24,21 26

2 Shoulder join-2 Tuni 19021 O/L 212 16,13,14 173 Neck rib folding & servicing Johura 20568 O/L 200 16,14,16 184 Neck rib edge joint Mukul 20918 P/M 225 14,12,12 165 Neck joint Sajida 3357 O/L 212 15,13,14 17

6 Piping shoulder to shoulder-1 Taslima 2199 F/L 120 26,23,25 307 Piping shoulder to shoulder-2 Arif 19799 F/L 157 18,20,18 238 Piping top stitch shoulder to shoulder-1 Rekha 20954 F/L 189 16,15,17 19

9 Piping top stitch shoulder to shoulder-2 Alal 3011 F/L 124 24,25,24 2910 Sleeve joint-1 Hasina 850 O/L 68 44,46,43 5311 Sleeve joint-2 Shapla 19930 O/L 72 42,40,43 5012 Arm hole position zigzag top stitch-1 Helena 18332 F/L 116 28,26,23 31

13 Arm hole position zigzag top stitch-2 Afsana 20922 F/L 113 26,29,27 3214 Side seam-1 Laboni 20145 O/L 65 48,44,45 5515 Side seam-2 Ashiq 19659 O/L 68 44,42,45 53

16 Side seam-3 Parvin 3360 O/L 72 41,42,44 5017 Side seam position zigzag top stitch-1 Mukta 2124 F/L 116 27,25,26 3118 Side seam position zigzag top stitch-2 Alpona 19564 F/L 129 23,24,22 2819 Arm hole point position tack(2T)-1 Khaleda 20878 P/M 106 28,30,27 3420 Arm hole point position tack(2T)-2 Hameed 7495 P/M 116 24,25,23 31

21 Sleeve hem-1 Sayeed 20871 F/L 113 25,28,28 3222 Sleeve hem-2 Hasan 20414 F/L 103 30,28,29 3523 Body hem Julhash 19927 F/L 200 14,16,15 18

24 Label make Sanjida 20011 P/M 300 10,11,10 12



Process time (3pcs)












Process time (3pcs)










One Composite Mills Ltd. Capacity check sheet U-1 (Line: 3)

Style no: 29694 Target: 180pcs/ hour Buyer: Collin’sOrder quantity: 18694 Description: T-shirtDate: 27-03-20013 Type: Basic



Process time (3pcs)


1 Shoulder join-1 Kajoil 19865 O/L 131 21,21,23 26

2 Shoulder join-2 Rehena 20617 O/L 180 14,16,17 193 Neck rib folding & servicing Reema 20306 O/L 192 13,14,17 184 Neck rib edge joint Sima 20827 P/M 206 13,14,15 175 Neck joint Any 20640 O/L 180 15,17,17 19

6 Piping shoulder to shoulder-1 Salma 22037 F/L 120 23,24,25 297 Piping shoulder to shoulder-2 Rina 20616 F/L 131 20,21,26 268 Piping top stitch shoulder to shoulder-1 Bulbuli 22038 F/L 169 17,17,16 20

9 Piping top stitch shoulder to shoulder-2 Laboni 19044 F/L 137 25,20,19 2510 Sleeve joint-1 Amena 20145 O/L 58 50,51,49 6011 Sleeve joint-2 Asadul 20839 O/L 68 43,40,44 5012 Arm hole position zigzag top stitch-1 Anwara 5037 F/L 103 30,27,28 34

13 Arm hole position zigzag top stitch-2 Johir 20928 F/L 107 24,29,29 3214 Side seam-1 Reena 19509 O/L 55 53,54,48 6215 Side seam-2 Nupur 19486 O/L 56 50,53,49 61

16 Side seam-3 Khadija 9384 O/L 56 51,51,52 6117 Side seam position zigzag top stitch-1 Mannan 20698 F/L 102 28,28,29 3418 Side seam position zigzag top stitch-2 Nargis 18289 F/L 120 24,24,25 2919 Arm hole point position tack(2T)-1 Tara 22060 P/M 102 28,29,26 3420 Arm hole point position tack(2T)-2 Rabea 19874 P/M 115 23,24,29 30

21 Sleeve hem-1 Rajib 21013 F/L 93 30,33,31 3722 Sleeve hem-2 Rojina 3361 F/L 96 29,30,30 3623 Body hem Ripon 20998 F/L 180 17,17,15 19

24 Label make Lota 19871 P/M 280 11,9,10 12



Process time (3pcs)

Avg. timeAvg. time with 20% allowance


2 Shoulder join-2 Rehena 20617 O/L 206 14,15,13 17

3 Neck rib folding & servicing Reema 20306 O/L 221 12,13,13 16

4 Neck rib edge joint Sima 20827 P/M 192 13,15,17 18

5 Neck joint Any 20640 O/L 192 15,15,14 18

6 Piping shoulder to shoulder-1 Salma 22037 F/L 124 24,23,23 28

7 Piping shoulder to shoulder-2 Rina 20616 F/L 151 18,20,19 23

8 Piping top stitch shoulder to shoulder-1 Bulbuli 22038 F/L 180 16,15,16 19

9 Piping top stitch shoulder to shoulder-2 Laboni 19044 F/L 124 22,22,25 28

10 Sleeve joint-1 Amena 20145 O/L 60 49,50,46 58

11 Sleeve joint-2 Asadul 20839 O/L 69 39,40,44 49

12 Arm hole position zigzag top stitch-1 Anwara 5037 F/L 99 31,28,27 35

13 Arm hole position zigzag top stitch-2 Johir 20928 F/L 115 24,25,25 30

14 Side seam-1 Reena 19509 O/L 58 50,48,49 59

15 Side seam-2 Nupur 19486 O/L 65 45,45,47 55

16 Side seam-3 Khadija 9384 O/L 55 53,55,55 65

17 Side seam position zigzag top stitch-1 Mannan 20698 F/L 102 31,26,28 34

18 Side seam position zigzag top stitch-2 Nargis 18289 F/L 115 24,25,25 30

19 Arm hole point position tack(2T)-1 Tara 22060 P/M 102 27,27,29 34

20 Arm hole point position tack(2T)-2 Rabea 19874 P/M 131 21,24,21 26

21 Sleeve hem-1 Rajib 21013 F/L 81 35,38,31 42

22 Sleeve hem-2 Rojina 3361 F/L 107 27,27,28 32

23 Body hem Ripon 20998 F/L 180 15,15,17 19




Process time (3pcs)






5 Neck joint Any 20640 O/L 206 15,14,13 17


















23 Body hem Ripon 20998 F/L 160 16,18,19 22


One Composite Mills Ltd.Capacity check sheet U-1 (Line: 4)

Style no: 29694 Target: 180pcs/ hour Buyer: Collin’sOrder quantity: 18694 Description: T-ShirtDate: 27-03-20013 Type: Basic



Process time (3pcs)


1 Shoulder join-1 Kohinur 9497 O/L 110 29,26,23 31

2 Shoulder join-2 Soriful 18066 O/L 180 15,19,18 20

3 Neck rib folding & servicing Moli 20524 O/L 164 20,17,18 22

4 Neck rib edge joint Popi 13051 P/M 192 14,13,17 18

5 Neck joint Sadia 19905 O/L 180 16,15,19 20

6 Piping shoulder to shoulder-1 Sahara 18461 F/L 125 25,21,23 28

7 Piping shoulder to shoulder-2 Helena 21050 F/L 164 16,20,17 22

8 Piping top stitch shoulder to shoulder-1 Kobir 21093 F/L 164 20,16,17 22

9 Piping top stitch shoulder to shoulder-2 Aklima 20118 F/L 96 31,29,30 36

10 Sleeve joint-1 Asha 1545 O/L 62 53,42,46 55

11 Sleeve joint-2 Motin 12080 O/L 70 38,42,43 49

12 Arm hole position zigzag top stitch-1 Rojina 20659 F/L 115 23,25,28 30

13 Arm hole position zigzag top stitch-2 Helena 20952 F/L 131 23,20,23 26

14 Side seam-1 Rahima 20416 O/L 58 53,48,50 60

15 Side seam-2 Sopna 9898 O/L 66 42,46,44 53

16 Side seam-3 Najmul 20173 O/L 58 48,52,50 60

17 Side seam position zigzag top stitch-1 Panna 7207 F/L 125 20,27,23 28

18 Side seam position zigzag top stitch-2 Rojina 19031 F/L 115 23,25,27 30

19 Arm hole point position tack(2T)-1 Rina 20535 P/M 99 31,26,29 35

20 Arm hole point position tack(2T)-2 Samad 21075 P/M 137 23,20,20 25

21 Sleeve hem-1 Manik 5183 F/L 76 37,38,40 46

22 Sleeve hem-2 Sahid 20658 F/L 82 36,33,35 42

23 Body hem Joynal 19341 F/L 180 14,19,15 19

24 Label make Moyna 21057 P/M 240 11,11,13 14



Process time (3pcs)




























Process time (3pcs)


























Data Analysis

Capacity check sheet U-1 (Line: 2)



Process time (3pcs)












Process time (3pcs)



2 Shoulder join-2 Tuni 19021 O/L 200 14,16,14 18

3 Neck rib folding & servicing Johura 20568 O/L 180 17,15,18 20

4 Neck rib edge joint Mukul 20918 P/M 257 11,14,12 14

5 Neck joint Sajida 3357 O/L 200 15,14,16 18

6 Piping shoulder to shoulder-1 Taslima 2199 F/L 129 24,23,21 28

7 Piping shoulder to shoulder-2 Arif 19799 F/L 138 21,24,22 26

8 Piping top stitch shoulder to shoulder-1 Rekha 20954 F/L 189 18,15,16 19

9 Piping top stitch shoulder to shoulder-2 Alal 3011 F/L 144 20,22,21 25

10 Sleeve joint-1 Hasina 850 O/L 67 44,44,46 54

11 Sleeve joint-2 Shapla 19930 O/L 73 41,42,40 49


13 Arm hole position zigzag top stitch-2 Afsana 20922 F/L 116 26,27,26 31

14 Side seam-1 Laboni 20145 O/L 62 47,48,50 58

15 Side seam-2 Ashiq 19659 O/L 69 44,42,43 52

16 Side seam-3 Parvin 3360 O/L 68 46,44,42 53

17 Side seam position zigzag top stitch-1 Mukta 2124 F/L 120 27,23,26 30

18 Side seam position zigzag top stitch-2 Alpona 19564 F/L 129 22,25,23 28

19 Arm hole point position tack(2T)-1 Khaleda 20878 P/M 113 30,25,25 32

20 Arm hole point position tack(2T)-2 Hameed 7495 P/M 129 24,22,23 28

21 Sleeve hem-1 Sayeed 20871 F/L 113 28,26,27 32

22 Sleeve hem-2 Hasan 20414 F/L 100 30,29,30 36

23 Body hem Julhash 19927 F/L 200 16,14,16 18




Process time (3pcs)



2 Shoulder join-2 Tuni 19021 O/L 200 13,14,17 18

3 Neck rib folding & servicing Johura 20568 O/L 200 15,13,18 18

4 Neck rib edge joint Mukul 20918 P/M 225 12,13,13 16

5 Neck joint Sajida 3357 O/L 225 14,12,13 16

6 Piping shoulder to shoulder-1 Taslima 2199 F/L 133 25,20,22 27

7 Piping shoulder to shoulder-2 Arif 19799 F/L 144 19,23,21 25

8 Piping top stitch shoulder to shoulder-1 Rekha 20954 F/L 200 17,14,15 18

9 Piping top stitch shoulder to shoulder-2 Alal 3011 F/L 144 23,21,20 25

10 Sleeve joint-1 Hasina 850 O/L 67 45,42,47 54

11 Sleeve joint-2 Shapla 19930 O/L 73 41,43,40 49


13 Arm hole position zigzag top stitch-2 Afsana 20922 F/L 116 28,24,26 31

14 Side seam-1 Laboni 20145 O/L 64 47,49,45 56

15 Side seam-2 Ashiq 19659 O/L 67 43,46,45 54

16 Side seam-3 Parvin 3360 O/L 65 44,46,47 55

17 Side seam position zigzag top stitch-1 Mukta 2124 F/L 116 28,27,24 31

18 Side seam position zigzag top stitch-2 Alpona 19564 F/L 124 25,22,24 29

19 Arm hole point position tack(2T)-1 Khaleda 20878 P/M 106 29,26,28 34

20 Arm hole point position tack(2T)-2 Hameed 7495 P/M 124 24,23,24 29

21 Sleeve hem-1 Sayeed 20871 F/L 100 27,33,29 36

22 Sleeve hem-2 Hasan 20414 F/L 100 29,31,29 36

23 Body hem Julhash 19927 F/L 189 17,15,15 19





Process time (3pcs)



2 Shoulder join-2 Rehena 20617 O/L 180 14,16,17 193 Neck rib folding & servicing Reema 20306 O/L 192 13,14,17 184 Neck rib edge joint Sima 20827 P/M 206 13,14,15 175 Neck joint Any 20640 O/L 180 15,17,17 19

6 Piping shoulder to shoulder-1 Salma 22037 F/L 120 23,24,25 297 Piping shoulder to shoulder-2 Rina 20616 F/L 131 20,21,26 268 Piping top stitch shoulder to shoulder-1 Bulbuli 22038 F/L 180 17,17,16 20

9 Piping top stitch shoulder to shoulder-2 Laboni 19044 F/L 137 25,20,19 2510 Sleeve joint-1 Amena 20145 O/L 58 50,51,49 6011 Sleeve joint-2 Asadul 20839 O/L 68 43,40,44 5012 Arm hole position zigzag top stitch-1 Anwara 5037 F/L 103 30,27,28 34

13 Arm hole position zigzag top stitch-2 Johir 20928 F/L 107 24,29,29 3214 Side seam-1 Reena 19509 O/L 55 53,54,48 6215 Side seam-2 Nupur 19486 O/L 56 50,53,49 61

16 Side seam-3 Khadija 9384 O/L 56 51,51,52 6117 Side seam position zigzag top stitch-1 Mannan 20698 F/L 102 28,28,29 3418 Side seam position zigzag top stitch-2 Nargis 18289 F/L 120 24,24,25 2919 Arm hole point position tack(2T)-1 Tara 22060 P/M 102 28,29,26 3420 Arm hole point position tack(2T)-2 Rabea 19874 P/M 115 23,24,29 30

21 Sleeve hem-1 Rajib 21013 F/L 93 30,33,31 3722 Sleeve hem-2 Rojina 3361 F/L 96 29,30,30 3623 Body hem Ripon 20998 F/L 180 17,17,15 19




Process time (3pcs)






5 Neck joint Any 20640 O/L 192 15,15,14 18


















23 Body hem Ripon 20998 F/L 180 15,15,17 19




Process time (3pcs)






5 Neck joint Any 20640 O/L 206 15,14,13 17


















23 Body hem Ripon 20998 F/L 160 16,18,19 22





Process time (3pcs)




























Process time (3pcs)




























Process time (3pcs)


























ResultFor day 1

For day 2

For day 3

After analysis we found the below result

Day 1

Day 2

Day 3

Conclusion

The contributions and incessant efforts of all the group members to complete the project report are highly appreciative. The challenging environment in 21st century demands that textile education should be meaningful and responsive to develop a mechanism to produce dynamic and technically competitive human resource in order to meet the challenges of the global world. Right and effective strategies needs to be adopted for affecting productivity with quality improvements in textile education thereby making it relevant and useful not only for the sustained growth and development of the textile institutes but also in serving the societies in a progressive way.

1. Yarn Manufacturing TechnologyLink : http://www.facebook.com/pages/Yarn-Manufacturing-Technology/485014954866808

2. Fabric Manufacturing TechnologyLink : http://www.facebook.com/pages/Fabric-Manufacturing-Technology/459520217425605

3. Garments Manufacturing TechnologyLink : http://www.facebook.com/pages/Garments-Manufacturing-Technology/472364799463126

3. Wet processing TechnologyLink : http://www.facebook.com/pages/Wet-Processing-Technology-Dyeing-/468645219825404

4. Fashion-Design-and-TechnologyLink : http://www.facebook.com/pages/Fashion-Design-and-Technology/587655294583875?ref=ts&fref=ts

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Line Balancing In Garments Industry

Education

production line

time study

assembly line balancing

balanced production

production problems

time better

production expectations

introduction line