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Minimization of reworks in the apparel industry

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

MINIMIZATION OF REWORKS IN QUALITY AND PRODUCTIVITY
IMPROVEMENT IN THE APPAREL INDUSTRY
1

Md. Mazedul Islam
Adnan Maroof Khan
2
Md.Mashiur Rahman Khan
1

Department of Textile Engineering, Daffodil International University, Bangladesh 1
Department of Apparel Manufacturing Engineering, Bangladesh University of textiles.
; ;

Abstract
The fast changing economic conditions such as global competition, declining profit margin, customer demand for
high quality product, product variety and reduced lead–time etc. had a major impact on manufacturing industries.
The demand for higher value at lower price is increasing and to survive, apparel manufacturers need to improve
their operations through-Producing right first time quality and waste reduction. This paper discusses the quality
and productivity improvement in a manufacturing enterprise through practical study. The paper deals with an
application of methodology in an industry which provides a framework to identify quantify and eliminate sources of
variation in an operational process, to optimize the operation variables, improve and sustain process performance
with well-executed control plans. The application of this paper improves the process performance of the critical


operational process, leading to better utilization of resources, decreases variations & maintains consistent quality
of the process output. The outcome of this observation reflected that an industry may gain higher productivity and
profitability with improved quality product by minimizing reworks activities. It also minimizes cost and improves
internal throughput time. A general overview over this development is given in this paper.

Keywords— Costs, Operation, Productivity, Profitability, product Quality, Reworks.
I. Introduction
As the global economic condition changing in a rapid
motion, generally in an industry more focus is given
on profit margin, customer demand for high quality
product and improved productivity. In garment
manufacturing, it is usual few rejected garments after
shipment. Reason, most of the manufacturers believe
that garments are soft goods and non-repairable
defect may occur due to low quality raw materials or
faulty process or employee casual behavior.
However, factory must have check points to control
over this issue. There is no ready-made solution that
can reduce rejection percentage overnight. Each order
is unique. But this paper works suggest how to
handle this issue and bring down rejection rate to
minimum. We see a lot of rejected garment after
shipment. Most of the organization termed these
garments as rejected because those garments can’t be

repaired by any means. Reworks in the garments
industry is a common works that hampers the smooth
production rate and focus poor quality products
having an impact on overall factory economy.
Minimization of reworks is a must in quality and

productivity improvement. Rework is a vital issue for
poor quality product and low production rate.
Reworks are the non -productive activities focusing
on any activity that customer are not willing to pay
for. Non-productive activities describe that the
customer does not consider as adding value to his
product. By reacting quicker in minimization of
reworks to make a product as per customer demand
with expected quality, the company can invest less
money and more costs savings. Therefore, a study
was carried out in the garment industry named Opex
& Sinha Textile Group located at Mirpur, Dhaka,

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

Bangladesh at cutting, sewing and finishing section
to identify reworks so as to eliminate them for saving

time,

2. Problem Definition and Methodology


6.

In the Apparel Manufacturing Industry, main raw
material is fabric; others are different types of
trimming and accessories. Operational wastages in
the Apparel manufacturing process are- top surface
rework, printed label rework, sewing fault rework,
pinhole rework, fabric rework Improper fly shape,
and other reworks. The general methodology
followed to minimize reworks is given below.

7.

8.
9.

1.

Review of the existing quality system in the
company
2. Identification of defects in the various
departments by collecting data from old
records
3. Analysis of data collected in order to
identify majorly occurring defects
4. Categorization of defects
5. Development of a model Quality Inspection
System
2.1. Review of factory existing Quality System


10.

11.
12.

13.

Fig. 1 Review of Existing Quality System

148

cost

and

improved

product

quality.

Implementation of check sheets to capture
defects in different departments
Training on concepts of quality, importance
of maintaining correct data, usage of the
collected data to analyze and solve quality
issues through the tools of quality
Introduction of Inline Inspection on Sewing
floor through a pilot run in one line

Training on the Sewing floor to QC’s,
supervisors and checkers on filling in the
format and on making Cause & Effect
Diagrams
Analysis of defects occurring in the check
sheets implemented in various departments
and devising suggestions to improve upon
them
Spreading of Inline inspection to other lines
Tracking of improvements and comparing
them with previous situation in different
departments
Visual communication of performance.


January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

2.1. Identification of Defects
The reports of quality inspections in various departments were studied for the period of January – April- 2012.
2.1.1 Cutting Department:
Percentage of lots

3%
21%

PASS
FAIL
HOLD
76%

Fig. 2 Lots percentages overview of cutting departments

2.1.2 Sewing Department
6.00

Defect categories wise D.H.U.

5.06
5.00
4.00
3.00

3.36

3.12
2.70 2.63
2.00

2.00

1.57

1.30 1.19

1.13 1.11 1.02 0.94

0.68

1.00

0.49 0.36 0.34

0.23 0.19 0.10 0.09

0.00
OPEN SEAMS
UNEVEN MARGIN
UNEVEN NECK/PLACKET/W.BAND
EXPOSED RAW STITCH
FULLNESS
UNEVEN GATHER
BROKEN STITCH
SHADE VARIATION
ZIPPER PLACEMENT

JOINT OUT
BALANCING OUT
PUCKERING
ROPING
WRONG LABEL ATTACH/LABEL MISSING
FABRIC DEFECTS
LOOSE TENSION
WRONG PANEL ATTACH
HOOK /LACE/ BUTTON PLACEMENT

Fig. 3 Defect categories wise D.H.U in the sewing department


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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

2.1.3 Categorizations of Defects
Sewing Defects: These defects are usually caused by
errors arising from wrong functioning of sewing
machines.
Seaming defects: These defects are usually caused by
errors arising from the interaction of the operator and
machine in the handling of garment.
Placement Defects: These defects are usually caused
by errors arising in marking and cutting as well as

sewing operations in the sewing room or a
combination of these
Fabric defects: These defects are usually caused by
errors arising from the fabric processing like knitting
and dyeing.
Embroidery defects: These defects are usually caused
by errors arising from the embroidery processing of
the garments.


2.1.4 Sewing Department Defects categories wise

Defect categories wise D.H.U. (Defects per Hundread Unit)
Total pieces inspected- 30030
Defects encountered-11778

25.00
20.73

D.H.U.- 39.22

20.00
D.H.U.

14.00

Where,

15.00

Seaming defects- 6224

10.00
5.00

Sewing defects- 4204
3.37
1.02


Placement defects-1012
0.10

0.00
Defect Categories

Fabric defects-307
Embroidery defects-31
SEAMING DEFECTS
SEWING DEFECTS
PLACEMENT DEFECTS
FABRIC DEFECTS
EMBROIDERY DEFECTS

Fig. 4 Defect categories wise D.H.U in the sewing department

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

2.2 Stages of Model Development

Identification of

various options at the
check points to capture
defects

Selection of various
tools to be used the
model

Developments of
model

2.3 Development of Model

Inline
Inspection
through Defect
Frequency
Rating System

Defect
capturing at the
End Line
through check
sheets

Analysis of
defects

Cause & Effect
Analysis of

highest
occurring
Defects

Effective
Solutions
Provided

2.4 Formats introduced in various departments.
1. Cutting audit format 2. Cutting pattern check
format. 3. Sewing in-line inspection format

4. Sewing end-line inspection format 5. Sewing cause
& effect analysis format. 6. Finishing initial
inspection format

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

4
9
2

5
2
5

4
2
3
35

1
4

3
1
1
11
20
4

2
2

5
3
4
1
5
3

2

9
9
7
4
3
3

2
2
3
2

1

3
3
3
1
3
2

2
2

2

72

3
2

14

2
27

1

30

5

2

3
2
55

70

Total Checked
Pieces

Others

Measurement out

Label Attachment

Uneven Raw
Margin

Exposed Raw stitch

56
4
9

10
13
2

56
8
42
11
77
4
42
8
78
6
67
8
75
3
70
15 139
5
97
5
55

4
116
7
203
9
151
11 139
12 207
12 135
3
87
2
70
1
94
134 2000

Table.1 Defect categories wise and percentage defectives in the sewing department

152

Percentage
Defective

2
6
10
1
3


1

Uneven Top Stitch

Uneven fly shape

Puckering

Roping

Broken stitch

4
6

Total Defective
Pieces

1-Mar
3-Mar
4-Mar
5-Mar
6-Mar
7-Mar
8-Mar
10-Mar 1
11-Mar
12-Mar
13-Mar
14-Mar

15-Mar
17-Mar
18-Mar
19-Mar
20-Mar
21-Mar
24-Mar
25-Mar
TOTAL 1

Slip stitch

Thread Tension

DATE

3.0 Experimental Sewing Data

56
22
22
5
12
16
17
10
23
17
11
12

18
14
17
29
14
8
8
8
339

100
52
29
12
15
24
23
14
17
18
20
10
9
9
12
14
10
9
11
9

17


January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

4.0 Cause & Effect diagram for major occurring defects and their implemented solutions
4.1 Measurement out of tolerance

Improper sweep shape
after panel attachment

Notches not proper

Solutions Provided
Cause
Notches improper at pleats

Improper sweep
panel attachment

shape

after


Solution
Cutting Department was informed about the cause and the reason
identified was misalignment of plies during cutting. This being a
major defect causing activity was asked to be checked 100% in the
audit before sending the bundles to sewing. A template was provided
against which the pieces were checked and in case of any deviation,
white pencil was used to mark pleat positions.
Bottom trimming was done to make the sweep uniform.

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

4.2 Puckering at waistband

Improper pre-setting of
waistband

Causes

Solution

Improper pre- setting of waistband after thumb

pressing

Pressing was done by steam iron with a spray of starch over it.
This made the handling of the waistband easier while stitching and
thus reduced puckering at the waistband.

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

4.3 Roping

4.4 Waistband extension uneven

Causes
Improper folder setting on machine

Solution
The folder guide was adjusted and improper materials
handling avoided

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

Causes
Margin not followed while attaching waistband and
waistband edge not finished properly

Solution
The operator was instructed to be careful while feeding
and following the margins strictly

4.5 Improper fly shape

Causes
Top stitch is being inhibited by zipper lock underneath

Solution
A template was provided to the operator and the stitch
was shifted a little below, altering the fly shape within
tolerance level

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

4.6 Fusing shining marks

Causes
Poor quality fusing used

Solution
Fusing was changed and skilled operator required

5.0 Trend chart showing reduction in defect levels after implemented solutions
D.H.U. levels in Measurement Out
60
40
20
0
1-Mar

2-Mar

3-Mar

Fig. 5 Defects level Reduction in Measurements Out


157

4-Mar


January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

D.H.U. levels in Puckering
25
20
15
10
5
0

Fig. 6 Defects levels Reduction in Puckering

D.H.U. levels in Roping

Fig. 7 Defects levels Reduction in Roping

D.H.U. levels in Uneven fly shape
40
30

20
10
0
3-Mar

4-Mar

5-Mar

158

6-Mar

19-Mar

18-Mar

17-Mar

16-Mar

15-Mar

14-Mar

13-Mar

12-Mar

11-Mar


10-Mar

9-Mar

8-Mar

7-Mar

6-Mar

14
12
10
8
6
4
2
0


January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

Fig. 8 Defects levels Reduction in Uneven Fly Shape


Defects levels in Label Attachment
16
14
12
10
8
6
4
2
0

Fig. 9 Defects levels Reduction in Label Attachment

Defects levels in Uneven Top Stitch
25
20
15
10
5
0
3-Mar

4-Mar

5-Mar

6-Mar

7-Mar


8-Mar

Uneven top stitch
Fig. 10 Defects levels Reduction in Uneven top Stitch

159

9-Mar

10-Mar

11-Mar

12-Mar


January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

6.0 Defects analysis in finishing department
239

250


206
200
150

132
106

100
50

4

3

3

0
SOIL/ DUST/ RUST
STICKER MARKS
SWEAT MARKS
VEGETABLE MARKS

OIL SPOT
INK/CHALK MARK
TOBACCO MARK

Fig. 11 Defects analysis in finishing department

6.1 Recommended Suggestions Implemented to Reduce Defects in finishing section
1.Oil spots: Application of a scrap paper under the

presser feet of sewing machines after the day’s work
so that the machines which are leaking oil can be
tracked.
2. Proper oiling level to be maintained in order to
prevent leakage of extra oil
3.Operator to take responsibility of cleaning the
machine after lubrication
4. Immediate reporting of oil leakage
Ink/ chalk marks: Usage of good quality markers, the
marks of which are easily washable 2.Avoid using
pencils for marking. 3. Usage of chalks on white and
light colored fabrics.

Soil and dust: 1.Usage of plastic bags for storing and
transportation of pieces. 2. Cleaning of checking
tables and machines before the start of day’s work 3.
Avoid keeping garments on the floor, using trolleys
for storage. 4. Creating a polyethene sheet partition
between sewing and finishing departments so that
fabric dust doesn’t come over to the finishing unit
and settle down on the washed fabric.
Suggestions implemented to reduce no. of uncut &
loose thread: 1.Thread cutting operation to be carried
out after washing in order to counteract unraveling of
threads after washing 2. Use of thread sucking
machine to prevent any loose threads to reach the
checkpoint

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

7.0 Department wise results and discussion (Sewing, Finishing and Cutting department)
7.1 Cutting Department

11/04/08

04/04/08

28/03/08

21/03/08

14/03/08

07/03/08

29/02/08

22/02/08

15/02/08


08/02/08

01/02/08

45
40
35
30
25
20
15
10
5
0

Fig. 12 Overall reductions in defect levels for cutting department

7.2 Sewing Department
Overall Percent defective trend

120
100
80
60
40
20
1-Mar
2-Mar
3-Mar
4-Mar

5-Mar
6-Mar
7-Mar
8-Mar
9-Mar
10-Mar
11-Mar
12-Mar
13-Mar
14-Mar
15-Mar
16-Mar
17-Mar
18-Mar
19-Mar
20-Mar
21-Mar
22-Mar
23-Mar
24-Mar
25-Mar

0

Percentage defective

Fig. 13 Overall reductions in defect levels for sewing department

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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

7.4 Finishing Department

March

Others

Touching

Mending

Cut & Hole

Wrong/Missing Label

Embroidery/Beads/Printing

February

Hard Stains

Insecure stitch


Uncut/ Loose thread

Stitching

Shade Variation

Fabric Fault

20
18
16
14
12
10
8
6
4
2
0

April 1- 15

Fig. 14 Overall reductions in defect levels for finishing department
Cutting lot failure rate reduced to zero percent
generally. Sewing percent defective reduced to
approximately 40%. In finishing, stitching D.H.U.
came down to approximately 8% from 16% as
earlier, uncut thread D.H.U. came down to
approximately 10% from 22% as earlier. Rework

increased the cost of the different work categories
between 2% to 30%. However, some best practices to
control defect generation within the factory were
suggested as- Make the workplace clean – from
fabric store to cutting to sewing to washing and
finishing. Place quality control system in proper
place. Implies that sufficient no. of checkers, trained
checkers, checkers making report while checking,
analysis of reports and take action based on the
quality check reports. Conduct training program for
the checkers on how to check piece correctly to
capture defective pieces. Train them to make garment

checking reports. Run quality awareness program for
your employees. Quality standard must be understood
by each employee and everybody have to work to
meet quality goal. No low standard work should be
accepted by the following department. In sewing line
don’t allow operators to keep bundles open and each
bundle must be completed before forwarding to the
next. It will help you track missing pieces. It is usual
experience that operators throw pieces under tables
when they make mistake or receive defective
(incomplete) garments from previous operator.
Nobody keeps track of these missing pieces until you
found shortage of garments in finishing. Set standard
operating procedures (SOP) for each task performed
by your employees. SOP for quality control system
for each department. Set audit team to audit your
quality system in a regular interval. These


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January 2013. Vol. 1, No.4

ISSN 2305-8269

International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

recommendations were suggested to the individual

department.

8. Conclusion
The suggestive tools developed in this article cover a
comprehensive series of aspects in minimizing
reworks in the sewing section of apparel industries by
ensuring quality production. The importance of the
textile industry in the economy of Bangladesh is very
high. The explosive growth of the RMG industry in
the country, however, has not been enough supported
by the growth of backward linkage facilities. So
manufacturing the quality product is mandatory to
sustain in this global competitive market. Quality is
ultimately a question of customer satisfaction. Good
Quality increases the value of a product or service,
establishes brand name, and builds up good

reputation for the garment exporter, which in turn

results into consumer satisfaction, high sales and
foreign exchange for the country. The perceived
quality of a garment is the result of a number of
aspects, which together help achieve the desired level
of satisfaction for the customer. However, we should
bear in mind that 1% defective product for an
organization is 100% defective for the customer who
buys that defective product. The study clearly
indicates that by eliminating non-productive activities
like reworks in the apparel industries time as well as
cost are saved by ensuring quality production which
have an important impact on overall factory
economy.

References
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Authors Biographies:
Md. Mazedul Islam
The author is associated as Lecturer in
the Department of Textile Engineering
at Daffodil International University,
Dhaka, Bangladesh. His research
interest fields are- Apparel production
and
Merchandising,
Production
Management. Industrial Engineering,
Apparel and fabric finishing, Textile
and Apparel Quality control, Apparel
Brand management, Apparel Washing
etc.
Adnan Maroof Khan
The author is associated as Lecturer in
the Department of Textile Engineering
at Daffodil International University,

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January 2013. Vol. 1, No.4

ISSN 2305-8269


International Journal of Engineering and Applied Sciences
© 2012 EAAS & ARF. All rights reserved
www.eaas-journal.org

Dhaka, Bangladesh. His research
interest
fields’
areGarments
Technology, Production Management,
Garments
Quality
Control
&
Management, Textile Coloration &
Fabric Structure and design, etc.
Md. Mashiur Rahman Khan
Assistant Professor & Head,
Department of Apparel Manufacturing
Engineering, Bangladesh University
of textiles.

164



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