Following are the common formulas those are used by garment industry professionals.

Formula#1: Daily Line Target = (Total working minutes in a day X No. of operators in a line X Line eff %) /Garment

SAM

Formula#2:

Individual operator target = (Total working minutes in a day X line efficiency %) /Operation SAM

Formula#3:

Individual operator Efficiency% = (units produced X operation SAM X 100)/Total minutes worked

While you are developing skill matrix for sewing operators, you need measure individual performance.

Secondly, if you plan to start performance based incentive scheme for individual operator, measuring

individual operator efficiency is essential.

Formula#4:

Line Efficiency% = (Line output X garment SAM X 100)/ (Number of operators X minute worked in day)

Note: include helpers and worker doing manual operations in case you have included SAM of those

operations.

Formula#5: Machine Productivity: Line output / No. of machine used

Machine productivity is measured in production per machine per shift day.

Formula#6:

Labor Productivity = Line output / No. of total manpower (operators +helpers)

Formula#7:

Line WIP (work in process) = Total pieces lie on the line for a particular order line

WIP of the line of an order is equal to Total pieces loaded till date minus Total piece out till date.

Formula#8:

Standard Time = (Observed time X observed rating) + Allowances

Allowances – Relaxation allowance, contingency allowance

Formula#9:

Machine utilization% = (Actual Machine running Time X 100) / Time available

Formula#10:

Cost per minute = Total cost incurred in labor / Total available working minute in a day X no. of labors

Formula#11:

Production Cost per unit = Total cost incurred in production in a day/ no. of garment produced in a day

Formula#12:

Man to Machine ratio = Total manpower of the factory / Total no. of sewing machines (utilized)

Suitable for printing and hanging near your work space when you need to see it most…

Two questions are -

1. What is the application of Industrial Engineering in apparel industry?

2. How Industrial Engineering concepts are used by apparel manufacturers?

What is the application of Industrial Engineering in apparel industry?

Industrial Engineering concepts are used in garment manufacturing to fulfill the following purposes -

Monitoring production floor and having better control over the production floor

Improving processes and improving method of working to increase factory's overall performance and

standardized garment manufacturing processes

Overall application of Industrial engineering can be explained better by describing common tasks of the IE

department. Common tasks of an IE department are as following but not limited to these

Work measurement of sewing operations, cutting room jobs and finishing jobs

Setting standard time for sewing operations and manual operations

Style analysis and conducting research and development (R&D) of the styles

Improving method of work and design workstation

Production planning and factory capacity determination

Work aids development

Work station designing and machine layout planning

Labor cost estimation

Performance measuring of workers

Training of workers (sewing operators)

Designing incentive scheme and calculating incentive for sewing operators

Setting line production target of the sewing lines and chasing production from line supervisors and

operators

Application of lean tools

How Industrial Engineering Concepts are used by apparel manufacturers?

Factories those are using IE techniques mostly have a complete IE set up (department). An IE department

consists of an IE managers (in-charge) and Industrial Engineers and juniors engineeTk. The strength of IE

team widely varies based on the maturity level of the department and on the focus of application of

Industrial Engineering. Without having enough team members, an IE department cannot work effectively.

Industrial Engineers are utilized in the following ways but not limited to those -

Factories apply all or few of the above listed functions to

Assist line supervisors by preparing resource requirement plan (machines and equipment and

manpower), line setting and line balancing etc.

assist production managers in target planning and production planning,

help merchandiser and marketing personnel by providing labor cost and production lead time,

help HR department by providing operator performance level, and help in operator recruitment

prepare MIS reports and show management team product status on daily basis and alert management

team if their attention is needed

set up standards operating procedures for new tasks, new process required for ever changing fashion

products

More than the regular jobs, IEs are also responsible for thinking of continuous process improvement.

Initiation of new projects and implementation of the project that has been undertaken, showing the

improvement opportunity within the factory to management team. Engineers are involved in performance

improvement tasks of the cutting department and finishing department.

IE Work Flow Chart

Still if you like to know about IE procedures, it can describe with a work flow. Most common tasks of an IE

are presented in an order in the following.

Style analysis --> Make operation breakdown --> Thread consumption calculation--> Making line layout on

paper --> Select m/c and equipment --> arrange guides and attachment -->Planning for production target -->

Setting line when new style is loaded --> Do line balancing --> Record production data --> Make production

reports --> Report to higher management (P.S. This is just an example of work flow).

Most IE tasks are aimed to make better work flow, improve utilization of resources, increasing factory

performance, and reducing production cost. As IE department get matured in a factory, it includes more

tools to help production team to increase the factory performance.

Work flow chart of IE department is shown in the following chart.

Implementation Procedure of IE Tools

IE procedure can be explained as the procedure of using Industrial Engineering tools. To learn how

Industrial Engineering tools are used by IEs in garment industry read on the following articles.

Time Study Procedure

Standard Minute Estimation Procedure

Operation Bulletin Preparation Procedures

Operator Training Procedures

Sewing Operator Recruitment Procedure

Thread Average Calculation.

There are two ways to find Cost of Manufacturing (CM) for a particular style/order.

1. Based on Standard Time (SAM) of the product

2. Based on Daily Production Average

1. CM Calculation Based on Standard Time (SAM) of Product Making

To get better accuracy in cost estimation one should prefer this procedure. But too many small size

companies no such resources available to measure product SAM and data for the following parameter Tk.

Following parameters are essential for cost calculation in this method.

1. Product SAM: Standard time of the garment. Standard time of a garment is measured by

using Time Study and using synthetic data.

2. Target Efficiency: Target efficiency percentage is at what % you are expecting running a

specific product and order quantity.

3. Operating Cost per day/machine - Operating cost is factory running cost. Operating costs

are all cost incurred to run the business other than material cost. Calculate monthly operating cost

and then calculate daily operating cost. Calculate per machine operating cost.

Formula:

Cost of Manufacturing = (Operating cost per day per machine* SAM)/(Target Efficiency% * Working hours

* 60)

In the following table an example is shown for calculating manufacturing cost using SAM and Daily

Production figure.

In the above example, garment SAM is 21 minute, target efficiency 60%. So, actual time would be 35

minute to make a garment. Factory works 8 hours in a day and operating cost per day per machine is Tk.

1022.

Cost of manufacturing is Tk. 74.52

2. CM Calculation Based on Daily Production Figure

This method is widely used by garment manufacturing factories. Cost of manufacturing calculation is done

based on historical production data. This is an easier method compared to above one.

Information needed to find Cost of Manufacturing

1. Daily production: Find average daily production of a particular style (garment) based on

earlier (historical) production figures. Calculate daily average production of the factory.

2. Manpower involved in production: How many sewing machines or sewing operators are

utilized to produce above quantity.

3. Operating cost per day/machine: As explained above.

Formula

Cost of Manufacturing = (Operating cost per Day / Total garments to be produced per day)

See the example method -2 in the above table. In the example, daily product is 550 pieces. 40 operators

worked to produce these pieces. Operating cost per machine is Tk. 1022 per day.

So cost of manufacturing is Tk. 74.33

P.S. Data used in the above examples are hypothetical.

Tools and Equipment used by Industrial Engineers

Industrial Engineers (IE) use various type of tools and equipment. What all equipment and tools to

use, depend on the job responsibilities of an IE in a company. Name of the common tools and equipment are

listed below. Purposes of the tools are also mentioned here.

Stop Watch (Digital or analog): Measuring observed time at the time of Time Study.

Measuring Tape: Measuring length of seams and measuring distances.

Digital Camera: Capturing videos for various

operations that help in motion analysis of operations.

Tripod for the camera: Used as camera stand.

Time Study board: Required during time study to hold

the Time Study format.

Calculator: Data calculation and report making.

Tachometer: to measure speed of the motor of sewing

machine. This equipment is used to find machine rpm.

Data capturing and process analysis formats: For

example- Time Study format, Motion analysis format

etc. Data capturing and analysis to bring improvement.

Various documents: Documents are used to assist

production and other processes with information,

methodology or layout. Formats are like Operation

Bulletin, Line Layout, Pitch Diagram, Hourly report

format etc.

Computer: Data analysis, Report making, Mailing, video analysis of operations etc.

Standard Hours Earned in Garment Manufacturing

Standard Hours Earned term is not much known in garment factories. Here, Work Study officers

or Industrial Engineers working in garment manufacturing factories (Export house or domestic garment

manufacturing) don't use 'Standard Hours Earned' instead engineers use Standard Minutes produced or

Standard Minutes earned. So when we heard this term first time, we think it might be a different measure.

Let me explain what ‘Standard Hours Earned’ means.

This is similar to Standard Minute Produced by workers. Instead of minutes it is presented in hours. To get

Standard hours earned value, standard minutes are divided by 60. Like, if an operator works for 8 hours a

day and produce garment equivalent to 360 minutes then operator’s standard hours earned would be 6 hours

(This is derived from: 360 minutes/60).

Formula for calculating standard hours earned:

Standard hours Earned = (SAM of operation X Garments produced)/60

This term is also called as Earned Hours because operator has earned that many hours by his/her effort.

Benefit of using Standard Earned Hours

- Easy to compare produced hours against available hours in a day (efficiency)

- Secondly calculating earning amount (in Dollar) of an operator from earning hours is easy as you know

standard hourly rate of your operators.

Operation Breakdown:

Breakdown is a listing of the content of a job by elements. A garment consists of some parts & some group

of operations. Breakdown means to writing down all parts & all process/operation after one another lying

with the complete garment according to process sequence. Prior to defining SAM of the garment, detailed

operation break-down is made by engineer. Both manual and machine operations are included in the

operation list. It is a must to write down the estimated SMV & type of machine beside each & every process.

Breakdown Procedure: APM, Technician Chief & Work-Study officer must sit together to make breakdown.

Technician breaks the garments into parts and gathered the parts one after another by operation/Process.

Then Work-Study officer & APM fix up the SMV of those operation

By preceding this technique when all process completed need to summarize all process SMV and the

total will be called as respective garment’s SMV.

Benefit of Breakdown: 1. Can see the all operations of the garment at a time.

2. Can anticipate the difficulties of doing critical operation

3. Can make layout in an easy, simple & less time consuming way

4. Can calculate the SMV for target setting & equal time distribution to the operator during layout.

5. Easy to select right operator for right process.

6. Can easily achieve the production target within a very short period.

Operation Breakdown and SAM of Full Sleeve Formal Men’s Shirt Prior to defining SAM of the garment, detailed operation break-down is made by

engineer. Both manual and machine operations are included in the operation list. Then a

skilled operator is given to do operations one by one. 5 to 10 samples are studied. All

operations are studied by GSD expert for motion analysis. At the same time all

operations are videoed for future reference. Calculated SAM of the operations for a

Formal Shirt has been shown in the following table. This has been defined by a GSD

practitioner of a large size Indian garment export company using GSD software. The

following SAM of each individual operation will help to understand how a shirt’s SAM

reach up to a certain value. The SAM of the operation may vary according to the

changes styling of the shirts, seam length, attachment and work aids used, motion sequence used by the

operator and machine type.

Product: Full Sleeve Men’s Formal Shirt. Brand: Arrow

Total Garment SAM: 22.32 minutes.

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

Operation Breakdown and SMVs of a Basic Jeans

Operation breakdown of a 5 Pocket Basic Jeans is listed in this article. SMVs mentioned here against each

operation are just for your reference. SMVs may vary according to machine types, workstation layout and

equipment used. Some of operations are done by automatic machines, like auto pocket hemming (APH),

auto pocket attaching (APS) etc. Machines that are used for the operations have been mentioned in third

column (M/c type) of the following table.

This Operation Breakdown has been taken from a Jeans manufacturing company in Vietnam.

Table 1: Operation Breakdown Chart

Sl. no. Operations M/C Type SMV

Back

1 pocket hemming APH 0.07

2 pocket o/l 3T O/L 0.3

3 pocket creasing ADPC 0.4

4 pocket attaching APS 0.74

5 second stitch @ back pocket

SNLS 0.65

6 back yoke attach FOA 0.41

7 back rise join FOA 0.24

8 size label attach SNLS 0.2

Front Section

9 coin pocket hemming APH 0.015

10 coin pocket attach @ jet piece (right)

SNLS 0.2

11 pocket bag attach with jet piece

5T F/L 0.42

12 o/l @ pocket bag 3T O/L 0.68

13 top stitch @ pocket bag

SNLS 0.4

14 o/l @ zipper fly 4T O/L 0.3

15 o/l front panels @ crotch

3T O/L 0.26

16 zipper attach @ left fly

DNLS 0.32

17 left fly attach @ front panel (inseam & top stitch)

SNLS 0.34

18 J-stitch @ left fly APJ 0.58

19 front pocket mouth hemming

DNFPH 0.3

20 Pocket bag stitch to front panel @side & top (wt w/c label@lt.)

SNLS 0.46

21 right fly attach with zipper & crotch join

SNLS 0.25

Assembly

22 loop preparation 3T F/L 0.15

23 main label attach @ waist band, & w/b joining in chain

SNLS 0.3

24 top stitch @ inseam FOA 0.55

25 side seam join (attach front & back panels)

5T O/L 0.65

26 top stitch @ side seam

SNLS 0.38

27 waist band stitch WBAM 0.38

28 waist band corners finish

SNLS 0.72

29 loop attach ABLA 0.65

30 bottom hemming BHM 0.33

Total 11.65

Full form of sewing machine name

APH - Automatic pocket hemming machine

ADPc - Automatic pocket creasing machine

APc - Auto pocket stitching machine

SNLS - Single needle lock stitch

FOA - Feed of the arm

3TO/L - 3 thread overlock (overedge)

5TF/L - 5 thread flat lock (cover stitch)

4TO/L - 4 thread over lock

5TO/L - 5 thread over lock

DNLS - Double needle lock stitch

3TF/L - 3 thread flat lock (cover stitch)

APJ - Auto J-stitch making

DNFPH - Double needle front pocket hemming

WBAM - Waistband attach machine

ABLA - Auto loop attach

BHM - Bottom hemming machine

(Note: Some of the machine names are short form of machine used for the specific operation

used by a company. Other companies may name it different way)

Denim is known as all-time fashion for all age group and for both sex. The demand of

denim pants are always there. To supply enough Jeans to the sourcing countries

entrepreneurs are setting plants in low labor cost countries. Bangladesh is one such example.

To reduce the manufacturing cost high end technology are used in denim plants with basic

machines. Specialized machines and semi-automatic machines are used in sewing, i.e. patch

pocket pattern making, surging panels and automatic patch pocket attaching. A plant of 500

machines can be set with following machine mix.

About the Contributor of this Denim topic: Md. Mostafiz Uddin is in the Apparel

Trade since 1999. Currently he is holding the post of Managing Director at Denim Expert

Ltd, a Denim Manufacturing Company.

Operation Breakdown and SMVs of a Basic Polo tee-shirt

We have done this experiment in SM Knitwear Ltd. Bangladesh.

We attempted this study for proper utilization of man and machine. We

made a little bit change of existing line balancing and process layout for

number of operations that was done by man power. In this experiment

we used auto machines in some operations instead of man power and

also find out the performed SMV after the modification of operations.

Process layout line balancing and SMV of Polo- shirt

Sl. No. Operations Machines Stitch type Man power

Performed

SMV

Helper Operator

1 Placket position mark Helper − 1 0.374

2 Placket fusing Iron man − 1 0.396

3 Body scissoring Helper − 1 0.33

4 +Both placket joint on front part LS 1N Lock Stitch 2 0.946

5 Placket nose tack LS 1N Lock Stitch 1 0.462

6 Placket raw edge cut Helper − 1 0.469

7 Lower placket close LS 1N Lock Stitch 1 0.418

8 Upper placket close LS 1N Lock Stitch 1 0.418

9 Placket security tack LS 1N Lock Stitch 1 0.396

10 Placket box LS 1N Lock Stitch 1 0.484

11 Body match Helper − 1 0.33

12 Shoulder joint with piping OL

Over edge

Stitch 1 0.44

13 Shoulder top stitch FL

Chain / Flatbed

Stitch 1 0.44

14 Collar mark Helper − 1 0.396

15 Collar over lock OL

Over edge

Stitch 1 0.806

16 Collar joint OL

Over edge

Stitch 2 0.418

17 Neck piping FL

Chain / Flatbed

Stitch 1 0.44

18 Neck top stitch LS 1N Lock Stitch 1 0.44

19 Main label joint LS 1N Lock Stitch 1 0.396

20

Sleeve match and shoulder piping

cut Helper − 1 0.33

21 Sleeve joint OL

Over edge

Stitch 2 0.682

22 Bottom hem FL

Chain / Flatbed

Stitch 1 0.352

23 Care label joint LS 1N Lock Stitch 1 0.374

24 Placket servicing OL

Over edge

Stitch 1 0.352

25 Side seam OL

Over edge

Stitch 2 0.77

26 Side slit tape measure and cut Helper − 1 0.33

27 Side slit tape attach LS 1N Lock Stitch 2 0.66

28 Side slit tape top stitch LS 1N Lock Stitch 2 0.704

29 Slit security tack LS 1N Lock Stitch 1 0.286

30 Button attach and hole mark Helper − 1 0.308

31 Button hole BH 1N Lock Stitch 1 0.297

32 Button attach BS 1N Lock Stitch 1 0.308

8 30

Total man= 38

Total SMV

≈14.552

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