Line balancing
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Transcript of Line balancing
Line balancing
© SOFT Student Handouts,By, Sunil Talekar, Faculty, SOFT-
Pune
What is line in apparel manufacturing?
Line: an assembly line composed of several work stations, at which specific operations are performed. To work effectively, with no work pile-ups between stations, the line must be balanced,e.g. work must get through each workstation in roughly the same amount of time.
What is Line Planning? Line planning is scheduling and allocating of orders to production lines according to product setting (product is being made in the line) and due dates of production completion. A line plan defines when a style is going to be loaded to the line, how many pieces to be expected (target) from the line and when order to be completed. For example, please refer to the following Table-1, where a simple line planning has been shown in spread sheet.
During booking orders or allocating orders to the production line, planners must check what is running on the line and how many days it will take to complete the Running style.
Benefit of Line planning: It helps production manager as well as line supervisor with information such as what is the daily production target for line. They set their line (machines and manpower) accordingly. Line plan also provides information such as how many days style would run, what is the next style going to be loaded?
Line plan
Line 1 Line 2 Total
DateDaily Prod.
Cumm Prod.
Daily Prod.
Cumm Prod.
Daily Prod.
1-Decloading #2341A, Qty -3000 pieces 300 1200 300
2-Dec 200 200 300 1500 5003-Dec 250 450 300 1800 5504-Dec 400 850 200 2000 600
5-Dec 400 1250loading #Polo ,
Qty -1500 pieces 4006-Dec 400 1650 0 0 4007-Dec 400 2050 100 100 5008-Dec 400 2450 300 400 7009-Dec 400 2850 350 750 750
10-Dec 150 3000 350 1100 500
11-Decloading #432K, Qty -5500 pieces 400 1500 400
12-Dec 100 100loading #YK45, Qty -4500 pieces 100
13-Dec 250 350 200 200 450
14-Dec 500 850 250 450 750
15-Dec 500 1350 400 850 900
16-Dec 500 1850 400 1250 900
17-Dec 500 2350 400 1650 900
18-Dec 500 2850 400 2050 900
19-Dec 500 3350 400 2450 900
20-Dec 500 3850 400 2850 900
21-Dec 500 4350 400 3250 900
22-Dec 500 4850 400 3650 900
23-Dec 150 5000 400 4050 550
Daily Prod. – Daily production or line outputCumm Prod. – Cumulative production of the style till date
LINE BALANCING
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 ”
LINE BALANCING (Process Organization) It is a system where you meet the production expectations and you can find the same amount of work in process in every operation at any point in the day.
WHY LINE BALANCING…@ the main job in line balancing is to eliminate or reduce wip (work in process) at bottleneck operations.
@ keeps inventory costs low, resulting in higher net income
@ allows operator to work all day long giving an opportunity to earn more money and increases his/her work effi ciency
@ keeps the prices low which turns into repeat sales
@ means better production planning
Line balancing in apparel manufacturing
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 .
LINE BALANCING TOOLS
Production sheetsDaily production report
The inventory levels by operation
Production boardsStop watch
Calculator
Line balancing in apparel manufacturing
STEPS TO A BALANCED LINESTEP 1. CALCULATION OF THE LABOR REQUIREMENTS AND CAPACITY STUDY THE REQUIREMENT OF WORKER DEPENDS UPON THE PROBABLE EFFICIENCY OF THE LINE SELECTED AND PERCENTAGE OF TIME THEY WORK.
List down all operations with operator name as per operation sequenceCheck cycle time for
each operation for five consecutive cyclesWith average cycle
time calculate hourly capacity of the operatorsWith the help of the hourly capacity, calculate the labour requirement
Line balancing in apparel manufacturing
STEP 2. OPERATIONAL BREAKDOWN AND SETTING THE TARGET
B.• With the capacity data set target
output per hour from one line.
C.• Target per hour = Total no of
operators X 60 /garment SAM
D.
• Current hourly operator production report is analyzed
STANDARD ALLOWED MINUTES OF EACH OPERATION
+A.
Line balancing in apparel manufacturing
STEP 3: TARGET SETTING
With the above step 1 & 2 data set your target output per hour from one line.
Generally it is calculated using following formula (Target per hour= Total no of operators X 60 /garment SAM).
Check current hourly operator production report. Draw a straight line with target output data on the line graph.
* The time at which the longest time is required is called “Bottleneck Process”* The state of line organization should be evaluated as “Organization Efficiency” * Pitch Time provides average time allotted to each worker. * Using the pitch time and Bottleneck Process Time.
STEP 4. IDENTIFICATION OF BOTTLENECK AREAS
A B C D E F G H0
20
40
60
80
100
120
140
1601st Bottleneck
area
Loss in balance
Loss in balance
2nd Bottleneck area
Loss in balance
Bottleneck process
Name of worker (In order of processes)
Work
Allotm
ent
Tim
e
Hanes
See picture of knitted trunk short, and develop operation breakdown and confirm possible bottleneck
STEP4. ELIMINATION OF BOTTLENECKS FROM THE LINE
Club operations where possible. Give the operator another operation with less work
content considering machine type and sewing thread colors. Shuffle operators. Operations that have low
work content use low performer while work content is higher use high performers.Add more operators at bottleneck operations.
Also compare the cost-benefits of putting additional machine into the line.
Improve workstation layout and improve methods
Do extra work at bottleneck operations.
Reduce cycle time using work aids and attachments
Methods of eliminating bottlenecks from the line
Line balancing in apparel manufacturing
FROM IMBALANCED LINE..
To Balanced line
All in all…
Sl. No.
Operation List SAM
1 Pinning to profile 0.234
2 Run stitch collar 0.219
3 Trim collar 0.285
4 Clip and turn collar 0.223
5 Crease collar 0.381
6 Top stitch collar 0.42
7 Run stitch (R/s) collar band 0.291
8 Crease collar band 0.317
9 Insert collar in neck band 0.799
10 Turn and crease collar 0.452
11 Attach bias piece to cuff 0.874
12 Crease cuff 0.458
13 Hem cuff 0.501
14 R/s cuff 0.565
15 Trim cuff 0.36
16 Turn cuff 0.527
17 Crease cuff bottom 0.566
18 Attach placket to sleeve 0.795
19 Lock and make diamond 1.026
20 Sew pleats (4 no.) 0.389
21 Hem right front 0.494
22 Attach front placket 0.603
23 Crease pocket 0.542
24 Hem pocket mouth 0.28
25 Attach pocket to front 0.861
26 Attach brand label and tack loop 0.589
27 Crease patch pieces 0.236
28 Attach patch piece 0.333
29 Sew pleats 0.278
30 Attach yoke to back 0.475
31 Top stitch back yoke 0.365
32 Join shoulder 0.64
33 Top stitch shoulder 0.656
34 Attach collar 0.535
35 Close collar with size label 1.01
36 Sleeve attach 0.862
37 Top stitch armhole 0.678
38 Top stitch side seam 1.036
39 Attach & close cuff 0.696
40 Top stitch cuff 0.524
41 Hem bottom 0.947
Total SAM 22.322
Product: Full Sleeve Men’s Formal Shirt. Brand: Arrow
From given table draw a line diagram as well balance the line.