calculation of standard minute value of t shirt

Advanced Garments Manufacturing Azmir Latif, MSc in textile Engineering

ABSTRACT

This research project is based on calculation of standard minute value of T-shirt. An experimental investigation for the distribution of SMV for each and every operation require for making a T-shirt and provides a clear and details concepts for determining line balancing, machine requirements, man power allocation for setting a definite target within a reasonable efficiency. This project is a details discussion and distribution of SMV which will assist to minimize SMV by having a better synchronization with man, machine, materials and methods to achieve higher efficiency.

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ABBREVIATIONS

BGMEA= Bangladesh Garments Manufacturing and Exporters Association.BTMC= Bangladesh Textile Mill CorporationBGWUC= Bangladesh Garments Worker Unit CouncilWTO= World Trade OrganizationLDC= Latest Developed CountryCBL= Center Back LineCFL= Center Front LineFOB= Free On BoardGOB= Government Of BangladeshC and F= Cost and FreightCIF= Cost, Insurance and FreightEPB= Exporter Promotion BureauCMT= Cost of Making with TrimmingCMO= Cost of Making OrderNSA= No Seam AllowanceBL= Bill of LadingCO= Certificate of OriginUD= Utilization DeclarationUP=Utilization PermissionLCA= Letter of Credit AuthorizationPSI= Pre-Shipment InspectionM and W= Men and WomenW and C= Women and GirlsXL= Extra Large(size)L= Large(size)M= Medium(size)S= Small(size)CAD= Computer Aided DesignCAM= Computer Aided ManufacturingPTS= Primary Textile SectorsGDP= Growth Domestic ProductGSP= Generalized System of PreferenceGATT= Generalized Agreement on Tariffs and Taxes

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MFA= Multi-Fiber ArrangementFY=Financial YearBY= Bas YearPTI= Private Textile IndustryVAT= Value added TaxTUF= Technology Upgradation FundETP=Effluent Treatment PlanUNIDO= United Nation International Development OrganizationP/C= Polyester + CottonT/C= Tetron + CottonBQSP= Bangladesh Quartet Support ProgrammeMOT= Ministry of TextileMOC= Ministry of CommerceBFQ= Better Fisheries QualityBWTG= Better Worker in Textile GarmentsEU= European UnionEPI= Ends Per InchPPI=Picks Per InchUNEC= United Nation Economic and Development CommissionTU= Trade UnionUNDP= United Nations Development ProgrammeILO= International Labor OrganizationIFTU= International Federation of Trade UnionIMF= International Monetary FundGB= Great BritainGM= General ManagerAGM= Assistant General ManagerPO= Production Manager/ Purse CSO= Chief Executive OfficerBE= Bachelor of EngineeringBTMA= Bangladesh Textile Mill Association

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ContentsName Page No

Title page i

Declaration ii

Certificate iii

Dedication iv

Acknowledgement v

Abstract vii

Abbreviations viii

List of the Figures xii

List of the Table xii

Chapter 1

General Introduction 1

1.1 General Introduction 2

1.2 History of T-Shirt 5

1.3 Object of the project work 11

1.4 Literature review 11

Chapter 2

Analytical Methods and Their Theoretical Aspects 13

2.1 Pattern making 14

2.1.1 What is pattern? 14

2.1.2 Principles of pattern making 14

2.1.3 Pattern making depends on 14

2.2 Marker making 15

2.2.1 Method of Marker making 15

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2.2.2 Procedure of marker making 15 2.2.3 Marker efficiency 15

2.3 Parts of a T-Shirt 16

2.4 Sample 18

2.4.1 What is Sample? 18

2.4.2 Flow chart of sample making 18

2.4.3 Sample preparation 18

2.4.4 Types of sample 19

2.5 What is SMV? 19

2.6 What is line balancing? 20

2.6.1 Importance of line balancing 20

Chapter 3

Materials and Methods 21

3.1 Introduction 22

3.1.1 Material used 22

3.2 Methods of making T-Shirt 22

3.3 Sewing 23

3.4 Machine Sequence of T-shirt Manufacturing Process 24

3.5 Line Balancing of T-shirt Manufacturing process 25

3.6 SMV study for a T-shirt 26

Chapter 4

Conclusion and Recommendations 27

4.1 Conclusion 28

4.2 Recommendations 29

4.3 Reference 31

4.4 Appendix 34

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List of the Figures

Figure 2.1 Sleeve of T-shirt 16

Figure 2.2 Back & Front part 17

Figure 2.3 All parts of t-shirt 17

List of the Table

Table 3.1 SMV study for a T-shirt 26

CHAPTER 1

GENERAL INTRODUCTION

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1.1 General Introduction

A T-shirt (or T shirt, tee-shirt, or tee) is a style of shirt. A T-shirt's defining characteristic is

the T shape made with the body and sleeves. It is normally associated with short sleeves, a

round neck line known as a "crew neck", and no collar.

Typically made of cotton fibers knitted in a jersey stitch, they have a distinctive soft texture

compared to woven shirts. The majority of modern versions have a body made from a

continuously woven tube, on a circular loom, so that the torso has no side seams. The

manufacture of T-shirts has become highly automated, and may include fabric cutting by

laser or water jet.

The T-shirt evolved from undergarments used in the 19th century, through cutting the one-

piece "union suit" underwear into separate top and bottom garments, with the top long

enough to tuck under the waistband of the bottoms. With and without buttons, they were

adopted by miners and stevedores during the late 19th century as a convenient covering for

hot environments.

As slip-on garments without buttons, they originally became popular in the United States

when they were issued by the U.S. Navy during or following the Spanish–American War of

1898. These were a crew-necked, short-sleeved, white cotton undershirt to be worn under a

uniform. It became common for sailors and Marines in work parties, the early submarines,

and tropical climates to remove their uniform "jacket", wearing (and soiling) only the

undershirt.[1]

They soon became popular as a bottom layer of clothing for workers in various industries,

including agriculture. The T-shirt was easily fitted, easily cleaned, and inexpensive, and for

those reasons it became the shirt of choice for young boys. Boys' shirts were made in various

colors and patterns. By the Great Depression, the T-shirt was often the default garment to be

worn when doing farm or ranch chores, as well as other times when modesty called for a

torso covering but conditions called for lightweight fabrics.[1]

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A V-neck T-shirt has a V-shaped neckline, as opposed to the round neckline of the more

common crew neck shirt. V-necks were introduced so that the neckline of the shirt does not

stand out when an outer shirt is worn over it, thus reducing or eliminating the visible cloth

above the outer shirt of a crew neck shirt.

The ready-made garment (RMG) sector is the life-blood of Bangladesh economy achieving

higher export growth every year. The sector is now the largest contributor not only to

overseas trade but also to the national economy.

Bangladesh textiles and RMG industry comprises 1,55,557 units – 1,48,000 handlooms units,

3,284 mechanized primary textile units, 5150 export-oriented readymade garments

manufacturing units and 273 garments washing-dyeing units. The sector is a major foreign

exchange earner for Bangladesh contributing 77 percent to the country's net exports. At the

end of the fiscal year 2011, total export of Bangladesh garments was worth US$ 23 billion, a

43 percent increase over the previous year, accounting for almost 25 percent of the GDP

(gross domestic product) [1].

A growing number of chief purchasing officers (CPOs) in European and apparel companies

are scrutinizing their sourcing strategies, as margin and supplier capacity pressure building

over the last several years has caused them to search for the next performance improvement

opportunity.

While China is starting to lose its attractiveness in this realm, the sourcing caravan is moving

on to the next hot spot. With Bangladesh having developed a strong position among

Europeans and US buyers, many companies are already eager evaluate the future potential.

However, the lure of competitive prices, available capacities and suppliers capacities offered

is being cautiously weighed against a prevailing insecurity created by the challenges inherent

in Bangladesh’s Ready-Made Garments (RMG) market [2].

Today’s business climate for clothing manufacturers requires low inventory and quick

response systems that turn out a wide variety of products to meet customers demand. It is

especially in the apparel industry that managers are trying to develop their current systems or

looking for new production techniques in order to keep pace with the rapid changes in the

fashion industry.

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Therefore, to develop a new system, good observation is needed. However to observe real

manufacturing systems is very expensive and sometimes cumbersome.

The rapid rate at which the whole process takes place, the interaction between workers, and

the different transition times between workers make it increasingly more difficult for a

human being to make correct decisions regarding how fast each operator should work in

order to continue the process, while at the same time keeping productivity high and

throughput at an acceptable level [3].

Construction of a quality garment requires a great deal of know-how, a lot of coordination

and schedule management. Clothing manufacturing consists of a variety of product

categories, materials and styling. Dealing with constantly changing styles and consumer

demands is so difficult. Furthermore, to adapt automation for the clothing system is also so

hard because, beside the complex structure also it is labor intensive. Therefore, garment

production needs properly rationalized manufacturing technology, management and planning

[4]. In garment production, until garment components are gathered into a finished garment,

they are assembled through a sub-assembly process. The production process includes a set of

workstations, at each of which a specific task is carried out in a restricted sequence, with

hundreds of employees and thousands of bundles of sub-assemblies producing different styles

simultaneously [5]. The joining together of components, known as the sewing process which

is the most labor intensive part of garment manufacturing, makes the structure complex as the

some works has a priority before being assembled [6].

Furthermore, since sewing process is labor intensive; apart from material costs, the cost

structure of the sewing process is also important. Therefore, this process is of critical

importance and needs to be planned more carefully [7]. As a consequence, good line

balancing with small stocks in the sewing line has to be drawn up to increase the efficiency

and quality of production. An assembly line is defined as a set of distinct tasks which is

assigned to a set of workstations linked together by a transport mechanism under detailed

assembling sequences specifying how the assembling process flows from one station to

another. In assembly line balancing, allocation of jobs to machines is based on the objective

of minimizing the workflow among the operators, reducing the throughput time as well as the

work in progress and thus increasing the productivity. Sharing a job of work between several

people is called division of labor. Division of labor should be balanced equally by ensuring

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the time spent at each station approximately the same. Each individual step in the assembly of

product has to be analyzed carefully, and allocated to stations in a balanced way over the

available workstations. Each operator then carries out operations properly and the work flow

is synchronized. In a detailed work flow, synchronized line includes short distances between

stations, low volume of work in process, precise of planning of production times, and

predictable production quantity [8].

Overall, the important criteria in garment production is whether assembly work will be

finished on time for delivery, how machines and employees are being utilized, whether any

station in the assembly line is lagging behind the schedule and how the assembly line is doing

overall[9] [10]. To achieve this approach, work-time study, assembly line balancing and

simulation can be applied to apparel production line to find alternative solutions to increase

the efficiency of the sewing line[11].

Since the late 1970s, the RMG industry started developing in Bangladesh primarily as an

export-oriented industry and the domestic market for RMG has been increasing fast due to

increase in personal disposable income and change in life style. The sector rapidly attained

high importance in terms of employment, foreign exchange earnings and its contribution to

GDP. Since buyer comes to this region for the lowest labor price ($0.11 per shirt for

Bangladesh, $0.26 for India, $0.79 for Srilanka), the quality of the garments, efficiency and

productivity of Bangladesh RMG sector remain ignored even in the tough competitive

market. Factories in Srilanka operate at 80% - 90% of efficiency, whereas in Bangladesh,

according to some experts, productivity is between 35% and 55% of efficiency with very few

exceptions. For the RMG sector in Bangladesh, productivity alone can make a difference

between life and death [12].

1.2 HISTORY OF T-SHIRT

Although the T-shirt is a staple piece of outerwear today for both genders, it originally started

out as an undergarment for men. Since then, it has undergone many transformations - from

the tie-dyed, baggy tee to the tight fitting tank top. Additionally, the overall length, cut,

fabric, and printing methods also continue to advance. Ironically, people now wear

undergarments, like sports bras, underneath their T-shirts, despite the fact that it was once

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used for the same purpose. After one hundred years of evolution, the appearance of the shirt

is still constantly changing.

Early Days

The first form that the T-shirt took was called a union suit. It originated out of New York, and

it was a very basic one-piece garment that was white in color and buttoned up the front. Once

the style of long underwear started to gain popularity, the P.H. Hanes Knitting Company soon

followed suit and released their own version in 1902; it was a two-piece men's undergarment

that looked similar to the union suit, but lacked its length. Eventually, in 1938, which was the

same year that Nylon became popular, Sears finally introduced their own T-shirt called the

"gob" shirt. It sold for 24 cents.

1950's - How the T-shirt Became Cool

Just like the Hanes Company saw potential in the union suit, Hollywood also quickly picked

up on the emerging trend. For example, James Dean's role in "Rebel Without a Cause," and

Marlon Brando's acting in "A Streetcar Named Desire," only fortified the T-shirt's growing

following. In 1948, Governor Thomas E. Dewey's slogan was, "Dew-IT with Dewey," which

was quickly printed on promotional T-shirts for the duration of the presidential campaign.

The Smithsonian Institute still displays the 1948 campaign shirt, and it continues to hold the

record as the oldest T-shirt with a printed slogan.

1960's - Tie-Dye and Slogans

During the 1960's, better known as the psychedelic generation, the T-shirt evolved yet again -

especially when plastisol was invented. This was a revolutionary new type of ink that was

perfect for the daily wear and tear that most T-shirts were expected to withstand; now the ink

was durable enough to last alongside the fabric of the shirt. During this decade, bright colors

and tie-dyed patterns were very popular, and clothing was often used as a catalyst for self

expression. For instance, anti-war slogan opposing Vietnam were often featured on shirts,

along with company logos and other types of pictures. In fact, even famous music legends,

like Janis Joplin and Jimi Hendrix, used to wear shirts inked with slogans and tie-dyed

patterns!

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1970s and 80s - Pop Culture

During the 70's and 80's, custom T-shirts continued to grow in popularity. In turn, this meant

that methods of mass production became necessary, along with new methods of printing, like

litho-transfer. For instance, malls became a commonplace to have a custom T-shirt printed on

the spot, and corporations, along with many rock bands, started to realize how powerful T-

shirts were in terms of sales and branding. One of the most important innovations of this era

was the wrinkle-free T-shirt, which was made out of a mix of polyester and cotton.

Present Day - The Internet and Customization

Today, T-shirts still remain an integral part of the fashion industry, where they are worn in

many different styles, colors, and fabrics. People regularly have shirts custom made for adult

and adolescent athletic teams, company use, self expression and as a branding tool. One of

the most defining characteristics of the modern day T-shirt is that it can be printed almost

instantly on demand. People can custom print any type of shirt they like, with almost any

kind of image, slogan or color imaginable, as long as they have access to the Internet.

Most Popular T-Shirts

Three of the most popular T-shirts that have consistently sold well and retained their

popularity include ones with Disney characters, the Coca-Cola logo, and album art from the

Beatles. Despite having started off as an undergarment, society now enjoys them as both

under and outer pieces of clothing. In fact, they're even layered occasionally to create a truly

custom appearance for the wearer. People from many different generations wear them for

casual and dress occasions, and they still continue to drastically evolve away from the one-

piece long underwear that they originated from. One of the most startling examples is the

tube top. However, like its 1960's cousin, the modern day T-shirt is still a channel for self-

expression, artistic license and protesting political movements.

iconic moments in the history of the T-shirt

In celebration of the 100th birthday of the beloved American classic.

By: Melissa Breyer

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Thu, Apr 11, 2013 at 04:50 PM

178Facebook 44Twitter 32Pinterest 9Google+

Ever since 1913 when the T-shirt was first included as standard-issue gear in the U.S. Navy,

the short-sleeved crew neck has become an essential part of the American wardrobe. Not long

after the Navy, the Army followed suit, paving the way for the T-shirt to become the go-to

top for dockworkers, farmers, miners and other workers who appreciated the comfortable

lightweight cotton and short sleeves. By the 1920s “T-shirt” became an official American-

English word in the Merriam-Webster dictionary.

In the 100 years of its history, the T-shirt has grown up from a workwear staple to one of the

most flexible garments known to mankind, an article of simple clothing that can be found in

just about any clothing store for anywhere from a few dollars to a few hundred. Or a few

thousand? Indeed, last year French fashion house Hermèsdebuted a crocodile T-shirt with the

not-so-humble price tag of $91,500, illustrating just how far the T-shirt has come.

In celebration of the beloved classic's centennial, here are some of the more memorable

moments that mark its 100 years. Happy birthday, T-shirt!

1913: The launch

Submariners, often working in close and hot quarters, are issued T-shirts and are able to work

in comfort, instead of restrictive clothing and itchy wool.

1944: Undershirt as unofficial uniform

The T-shirt is adopted as the unofficial uniform of workers across the board, from mechanics

and miners to farmers and factory workers. Here, the T-shirt as worn by a U.S. Merchant

Marine oiler.

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1951: The Hollywood debut

The T-shirt goes sexy when hunky Marlon Brando does it justice in "A Streetcar Named

Desire." Teens go nuts for the look, and by year's end, T-shirt sales total $180 million.

1955: Rebel chic is born

James Dean follows up on the sexy T-shirt trend in "Rebel Without a Cause."

1950s: Print happens

Miami company Tropix Togs acquires exclusive rights from Disney to print images of

Mickey Mouse and pals (as well as Florida resort names) on T-shirts to promote tourism and

the the Disney brand — and thus, the advertising T-shirt is born.

1960s: The rock T blossoms

Album artwork like the "tongue and lips" design for The Rolling Stones, the prism design for

Pink Floyd, and Grateful Dead cover art by Stanley Mouse, are emblazoned across rock and

concert T-shirts as the screen printing industry evolves.

1967: Message shirts become wearable placards

The T-shirt goes pop art and political when Warren Dayton pioneers art T-shirts featuring

images of Cesár Chavez, the Statue of Liberty, polluted lungs and other political and comic

images.

1969: Ta-da, tie-dye!

Rit dye advertising genius Don Price markets the waning-in-popularity dye as way to turn

mundane shirts into psychedelic tie-dye masterpieces. Price arranges for hundreds of tie-dyed

shirts to be made and distributed to attendees and performers at Woodstock in 1969,

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clinching the tie-dyed T-shirt's place in the hippie movement — and boosting Rit company

profits at the same time.

1970s: The ironic T-shirt is formalized

The tuxedo T-shirt. Well, there's really just no explanation...

1977: The world hearts T-shirts

Advertising agency Wells Rich Greene is hired to develop a marketing campaign for New

York state. Graphic designer Milton Glaser comes up with a logo including the letter "I"

followed by a heart symbol and the state abbreviation. The logo is quickly adopted by

souvenir T-shirt makers, taking tourists by storm and initiating hordes of imitators.

1984: What happened in Miami, didn't stay in Miami

The T-shirt goes designer in the oh-so-1980s when Sonny Crockett (Don Johnson) sports a T-

shirt as part of an ever-changing, candy-colored wardrobe on the television series "Miami

Vice." The look, replete with rolled-up jacket sleeves and slip-on sockless loafers, takes off

like wildfire. To this day, the T-shirt-and-jacket combo persists.

2000s: Meme mania

The "Three Wolf Moon" T-shirt becomes an Internet sensation thanks to a humorous

Amazon review, which then spawns thousands of likewise comedic comments. Sales go

through the roof for the shirt's creator, The Mountain T-shirt company, the same company

responsible for the "Big Face" animal T-shirts, which are vying for an iconic moment of their

own.

2012: The message becomes the media

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Although still in prototype mode, the world’s first programmable T-shirt, tshirtOS, is a

collaboration between Ballantine’s and wearable tech company CuteCircuit. Forget those old

screen-printed classics; this high-tech T boasts an LCD screen that lets you display Facebook

statuses, tweets and even Instagram snaps.

1.3 OBJECTS OF THE PROJECT WORK

To calculate the SMV of T- shirt.

To determine line balancing

To determine operational sequence of the manufacturing process of T-shirt

To develop the target of the manufacturing process

To increase the productivity of the company

To make proper distribution of SMV

To make better utilization of man, machine and materials

1.3 Literature of review

There are small little no. of works have been done in this regard. Some literature are

mentioned below.

Asmara solones describe her statement in textile leaner. Blogspot.com that ……

The statement tee has always been around seems like, and in fact they’re making a huge

comeback this fall. Everyone’s got one, but do you know how long it’s been since the first

words were printed out on a shirt? They were replaced by iconic logos for a while before the

words came back in vogue, as in ”Frankie Says Relax”. The existence of the t-shirt dates way

back to the 1890s as an undergarment. However it was not until 1942 that t-shirts became

appropriate to wear on their own and even get something to say on them. This Air Corps

Gunnery School t-shirt featured on the cover of LIFE magazine of July 13, 1942, is believed

by many to be the first printed t-shirt ever worn publicly [13].

D Stuart describes his statement in www.onlineclothingstudy.com that …..

Select one operation for which want to calculate SAM. Take one stop watch. Stand by side of

the operator. Capture cycle time for that operation. (cycle time – total time taken to do all

works needed to complete one operation, i.e. time from pick up part of first piece to next pick

up of the next piece). Do time study for consecutive five cycles. Discard if found abnormal

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time in any cycle. Calculate average of the 5 cycles. Time you got from time study is called

cycle time. To convert this cycle time into basic time you have to multiply cycle time with

operator performance rating. [Basic Time = Cycle Time x performance rating] Performance

rating. Now you have to rate the operator at what performance level he was doing the job

seeing his movement and work speed. Suppose that operator performance rating is 80%.

Suppose cycle time is 0.60 minutes[14].

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CHAPTER 2

ANALYTICAL METHODS

AND

THEIR THEORITICAL ASPECTS

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2.1 PATTERN MAKING

2.1.1 What is Pattern?

A pattern is the actual copy of different parts of a garment that is made by cutting board paper

after sketching on it. According to this pattern cloth is cut and then garment is made. For

industrial production different patterns are made for different size and a marker is made with

these different patterns for a large-scale production. Then many cloths are cut at a time and

finally garments are made by large number of workers in garments industry.

Functions: Now making a pattern has some functions. These are as follows:

1. To sketch the parts primarily according to the body on paper.

2. To make pattern for different size by increasing measurements.

3. To make a marker for large-scale production.

4. To use these patterns made by standard body measurement for many times.

Finally to save time and money to make fast and cheaper production

2.1.2 Principles of Pattern Making:

A garment sewing patterns or garment fabric and patterns draft is developed by calculating,

taking about the following measurements:

1. Direct sample.

2. Specification sheet/ measurement chart.

3. Actual body size measurements.

4. Easy allowances.

5. Sewing allowance.

2.1.3 Pattern Making Depends On

1.Skills and technological knowledge

2.Analysis of design.

3.Experience of garments making.

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2.2 Marker Making:

Marker is a thin paper which contains all necessary pattern pieces for all sizes for a particular

style of garments in such a way that fabric wastage would be the least. The width of a marker

is generally taken as minimum width and the length of a marker depends on some factors.

2.2.1 Methods of Marker Making

A. Manual method:

1.One way marker

2. Two way marker

3. Group way marker

4. Head to head marker

B. Computerized method:

1. Automatic marker

2. Interactive marker

2.2.2 Procedure of Marker Making

There are two types of manual marker making and they are -

(a) Marker making with full size pattern

(b) Marker making with minimized pattern

In marker making with full size pattern, all patterns are prepared in full dimension according

to standard measurement in the sample section. The hard patterns are placed on marker paper

and marked by turning different direction due to minimize the fabric usage. Finally the whole

marker paper is placed on the fabric lay and cut as the direction of the marker paper.

2.2.3 Marker Efficiency

The marker planner measure his success by the efficiency of the marker plan created.

The higher the marker efficiency the lower the fabric wastage Internationally standard marker

efficiency is 75% by means of CAD.

Marker efficiency = (Area of pattern pieces in the marker plan ×100) / Total area of the

marker plan

Let,

Different measurement of a full sleeve basic T-shirt is as follows

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Area of front part = 56×24×2 = 2688square cm

Area of back part = 56×44 = 2464square cm

Area of sleeve = 40×24×2 = 1920square cm

Area of yolk = 38×8 = 304square cm

Area of collar = 36×10 = 360 square cm

Area of cuff = 22×7×2 = 308square cm

Area of pocket = 15×12 = 180square cm

Total area of patterns =8224 square cm

Let,

The no. of shirt is 24 pieces, the area of patterns = 8224square cm×24pieces

= 197376 square cm

Length of marker plan = 2594cm

Width of marker plan = 90cm

Area of marker plan= 2594×90=233460 square cm

Therefore, marker efficiency = (197376 x 100)/233460 = 84.54%

2.3 PARTS OF A T-SHIRT:

Fig 2.1: Sleeve of t-shirt

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Fig 2.2: Back & Front Part

Fig 2.3: All parts of T-shirt

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2.4 SAMPLE

2.4.1What is SAMPLE:

Sampling is process of development of a garment according to the tech-pack received by a

buyer copying of a garment with specifications de-marked by the buyer. There are different

stages of sampling. Sampling helps in proper development of a product and it also acts as a

milestone to in the confirmation of an order.

2.4.2Flow Chart of Sample Making:

Flow Chart of Sample Making

Garments Design or Sketch ( Manually or Computerized ) ↓

Basic Block ( Manually or Computerized ) ↓

Working Pattern ( By Machine ) ↓

Sample Garments ( Manually ) ↓

Problem of Production or Production Related Matter

↓Costing.............................................↓ ..................................Send to Buyer

↓Approved Sample

↓ Production Pattern ( By Hand or Computer )

2.4.3 Sample Preparation:

In this stage a sample is made to get approval of the buyer.It is the primary section of

garment industries. This section does all purposes from pattern design to sample making.

This section is used for-

A) Making sample garment for approval.

B) Making pattern sets for bulk production when needed.

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Flow chart of sample preparation:

Developed sample or fit sample make and cost determine

Sent to the buyer for getting approval

If no comment on cost order place

Graded sample make and sent to the buyer

Green seal sample and sent to the buyer

Gold seal sample and sent to the buyer

If gold seal approve

Size set s

2.4.4 Types of Sample:

1. Approval Sample

2. Counter

3. Salesman

4. Fashion show

5. Photo

6. Pre production

7. Production

8. Shipping

2.5 WHAT IS STANDARD TIME OR SMV

SMV means standard minute value. It is a numerical value which is represented the standard

time of a process or operation in a standard environment for standard worker. To convert

cycle time to normal or basic time we have to multiply it with operator performance rating.

Here for example, if rating 100%. Now we have add allowances for machine allowances,

fatigue and personal needs etc. Add machine allowance only to those elements where

machine is running and fatigue and personal needs to all elements. Now we got standard time

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for each element in seconds. Sum up all elemental time and convert seconds into minutes.

This is Standard Minute Value (SMV).

Let,

Cycle time = 36 sec.

Performance Rating = 80%

Bundle allowance, M/C allowance & Personal allowance = 20%

SMV or Standard minute

= Normal or Basic time + Allowance%

= [Cycle time (Second) /(60 x Performance rating%)] +Allowance %

= [36/60 x 80/100] + Allowance%

= 0.48 + [(20 x 0.48)/100]

= 0.48+0.096

= 0.576 Minute

2.6 What is line balancing?

A production strategy that involves setting and intended rate of production for required

material to be fabricated within a particular time frame. In addition, effective line balancing

requires assuring that every line segment’s production quota can be meet within the time

frame using the available production capacity.

2.6.1 Important of line balancing:

1. Line balancing helps to know about a new machine required for new style.

2. It becomes easier to distribute particular job to each operator.

3. It becomes possible to deliver goods at right time at the agreed upon price.

4. Good line balancing increase the rate of production.

5. Line balancing help to compare required machinery with the existing one and compare

balance.

6. IT also help in the determination of labour requirement.

7. Good balancing reduces production time.

8. Profit of a factory can be ensure by proper line balancing.

9. Proper line balancing ensure optimum production at the agreed quality.

10. It reduces faults in the finished product.

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CHAPTER 3

MATERIALS AND METHODS

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3.1 Introduction

In sewing section there are various types of product are produced such as T-shirt, polo shirt,

tang top, Hollywood style, jepsy top, jacket, hoody jacket, under wear, trouser, sportswear,

swimming wear and so on. To produce these types of garments different type of materials are

used such as-

3.1.1 Material used:

single jerssey(lycra)(Hundred percent cotton)

Pattern paper

Measuring Tape

Scissor

Pencil

Eraser

Curve Ruler

3.2 METHOD OF MAKING T-SHIRT:

I am getting a lot of visits from people goggling "how to make a t-shirt" so I thought I'd oblige you.

First off, you need a pattern. You can trace one from an existing shirt, but I'm not covering that step in this tutorial. I'm using the size 4 t-shirt pattern from my beloved vintage Sew for Toddler. All the patterns for this book are on a large pattern sheet and you have to trace off the size you want. I usually trace my patterns onto freezer paper. If you look closely you can see I traced the wrong size first; I don't remember what happened there but it was one of two tracings I have of this pattern. My pattern has 4 pieces: front, back, sleeve, and neckband.

I have a pretty big piece of this fabric, so to waste the least amount of fabric and also be able to manage the whole thing, I cut out one pattern piece at a time. I'm starting with the front--the center front edge needs to be on placed on the fold of the fabric. I look closely at the fabric and make sure the tiny knit stitches are running straight (not at an angle) with my foldline. Also, the stretch of this fabric is going up and down in the photo, or across the body of the t-shirt front and back pattern pieces. You want to cut your knits out with the stretch going the right way.

Then I do the same with the back. First I cut off the small amount of scrap from cutting the

front and then I refold the fabric wide enough to do the back. Here you can see my cute

pattern weights. I don't pin my patterns--I use pattern weights and rotary cut around the edges

27


of my patterns. You can use scissors if you don't have a rotary cutter. I need to sharpen my

scissors and get a new rotary blade--cutting this out wasn't as easy and fun as it should have

been.The sleeve. Again I refold so I have enough width to lay out the sleeve pattern. See that

long straight line? It's the pattern grain line and should line up with the grain of the fabric. In

other words, line up with straight up and down lines of knitted stitches in the fabric. If you've

ever had a t-shirt that twisted around your body when you were wearing it, it was cut off

grain. It's not hard to make sure your fabric and patterns are on grain when you're cutting.

Neckline ribbing. This faric is laid out with the stretch going left to right. The pattern piece is

laid on the fold. I used a cotton/lycra rib knit for this piece. If your main shirt fabric is ribbed

or fairly stretchy, you can use the same fabric for the neckline. This shirt fabric is a jersey

that's not really stretchy enough to go over my boy's head and not have stitches pop right

away.

3.3 SEWING:

Sewing step 1: Place front and back pieces together with right sides facing. Match the pieces up at the shoulder and pin them if you want.Here they are serged together. Before I had a serge I would sew the seam, then zigzag the edges together because I don't like unfinished edges.

Sewing step 2: Pin the top center of the sleeve to the shoulder seam.

Pin the front and back edges of the sleeve seam. This is kind of difficult to show in a photo

Sewing step 3: Fold the shirt so the front and back line up and the sleeve edges line up.

Starting at the sleeve hem edge, and all at once, sew the sleeve edges together, then the front

and back together at the sides. Do both sides

Sewing step 4: Sewing the neckband on is explained here in T-shirt

Sewing step 5: Fold the sleeve edges and bottom edge up once and stitch in place. I have a "why you don't need a free arm to sew hems of small sleeves".

28


3.4 MACHINE SEQUENCE OF T-SHIRT MANUFACTURE PROCESS:

Number matching front to back part( back on part on upper side)

Shoulder joining by over lock m/c)

Interlining by fusing

Over locking of lining by over lock m/c

Piping ( with collar piped) by over lock m/c

Join edge of the pipe by plain m/c

Neck joint by plain m/c

Neck over locking by over lock m/c)

Neck piping round the neck by flat lock m/c

Round neck finished cut by plain m/c

Main label attaching by plain m/c

Sleeve hem by flat lock m/c

Sleeve Joint by over lock m/c)

Side Seam by over lock m/c)

Care label joining by plain m/c

Side top stitch by flat lock m/c

Side tuck cuff by plain m/c

29


Neck top stitch by flat m/c

Bottom hem by flat lock m/c

Inspection

3.5 LINE BALANCING OF T-SHIRT MANUFACTURING PROCESS FOR 180 PIECES PER HOUR:

No. of m/c

Shoulder joining-(O/L) = 1

Over locking of lining-(O/L) = 1

Piping- (O/L) = 1

Neck joining-(O/L) = 1

Neck overlocking-(O/L) = 1

Sleeve hem-(F/L) = 1

Sleeve joining-(O/L) = 2

Side joining-(O/L) = 3

Side top stitch-(F/L) = 2

Side tuck cuff-(SNLS) = 1

Neck top stitch-(F/L) = 1

Bottom hem join(F/L) = 1

30


Table 3.1 SMV study for a T-shirt

No. Operation Average Cycle

time(sec)

Estimated

SMV

01 SMV for shoulder

joining

13.09 0.30

02 SMV for over locking of

lining

10.90 0.25

03 SMV for piping 13.09 0.30

04 SMV for neck joining 15.27 0.35

05 SMV for neck

overlocking

13.09 0.30

06 SMV for sleeve hem 13.96 0.32

07 SMV for sleeve joining 26.18 0.60

08 SMV for side joining 34.90 0.80

09 SMV for side top stitch 26.18 0.60

10 SMV for side tuck cuff 26.18 0.60

11 SMV for neck top stitch 15.27 0.35

12 SMV for bottom hem

joining

15.27 0.35

TOTAL SMV 5.12

31


CHAPTER 4

CONCLUSION

AND

RECOMMENDATIONS

32


4.1 Conclusion:

This project has come to termination finally after lots of thinking discussion and I

uninterrupted trying. I really have worked hard to complete this project well ahead. I would

like to make it as a replica of production so that it provides a complete knowledge about T-

shirt. Through there where some limitation like shortages of time that compelled me to

completed the thesis as soon as possible, even then I have tried to give my best.As I are found

that SMV for a T-shirt is 6.14.I have found during my thesis that SMV of a T-shirt increased

in terms of decorative garments and there is a decrease of productivity.On the other hand

SMV decreased on the less decorative garments.As a result productivity of garments is

increased.Above discussion it is clear that currect SMV calculation is the key factor for

garments productivity.

33


4.2 Recommendation:

When I look into the processes and operations during my project work in Rupa Fabric Ltd., I

have found improvement potential is there in the factory. But, there are few points that might

be taken into consideration for improving the productivity.

Efficiency as well as productivity would have been better if I would have taken

some large quantity e.g. 25,000 pieces order.

Balancing the process is highly related to the type of machines as machine utilized

in bottleneck and balancing process should be similar.

Skilled operators should be in right place. If, it not happens then after couple of

hours, high skilled operators start sitting idle and low skilled operators stuck with

their work. Thus line becomes imbalanced and lot of productive time is lost as

operators sit idle. On this occasion, skilled workers are eligible for the production

processes and proper training and supervision is essential to achieve the optimum

improvements on productivity and efficiency.

They should use pitch diagram method to find bottlenecks inside the line and also

have to minimize bottleneck operations by balancing operations.

A straight assembly line with center table at left side is good for a product that has

no preparatory work and individual operation SAM is nearby the pitch time. When

a style includes lot of preparatory work (for garment parts), it is better to make

garment parts in sections and assemble them later. If possible use overhead

transportation system.

34


Raw materials input should be available as per operators’ efficiency.

There are some kinds of time saving devises such as folders, guides ,attachments,

correct pressure foots etc. that facilitate operators’ to perform their work

effectively with less effort.

Instead of giving equal target to all operators working in a line, give individual

target as per operators’ skill level and capacity.

Operators’ will is the most crucial part in productivity improvement. If they are

motivated, they will put enough efforts on the work. Employee motivation

generally depends on various factors like working atmosphere, HR policies and

bonus on extra effort or achieving target.

35


REFERENCE

36


4.3 References

1. RahmanMizanur, (Thursday, 06 December 2012). RMG sector: Secret of success and

causes of unrest, senior vice- p resident (IBBL),

2. Berg Achim, November 2011,Principal, McKinsey’s Frankfurt, Co-coordinator,

McKinsey’s Apparels, Apparel, Fashion & Luxury Practice,

3. Mücella G. Güner, Can Ünal, Department of Textile Engineering, Faculty of Engineering,

University of Ege, Izmir, Turkey, Line Balancing in the Apparel industry Using

Simulation Techniques, FIBRES & TEXTILES in Eastern Europe April / June

2008, Vol. 16, No. 2 (67), p-75.

4. Glock, R. E. & Kunz, G. I. (1995). Apparel Manufacturing-Sewn Product Analysis,

Prentice Hall ,New Jersey, p:4

5. Chuter, A. J. (1988). Introduction to Clothing Production Management, Blackwell Science,

Oxford, pp. 60-63.

6. Cooklin, G. (1991). Introduction to Clothing Manufacturing, Blackwell Science, Oxford, p.

104.

7. Tyler, D. J. (1991). Materials Management In Clothing Production, BSP Professional

Books Press, London.

8. Eberle, H., Hermeling, H., Hornberger, M., Kilgus, R. ,Menzer, D., Ring, W., (2004).

Clothing Technology, Beuth-Verlag GmbH, Berlin.

9. Glock, R. E. & Kunz, G. I. (1995). Apparel Manufacturing-Sewn Product Analysis,

Prentice Hall, New Jersey, p: 4.

37


10. Hui, C. & Ng, S. (1999). A study of the effect of time variations for assembly line

balancingin the clothing industry International Journal of Clothing Science and

Technology, Vol.11, pp. 181-188.

11. Kursun, S. &Kalaoglu, F. (2009). Simulation of Production Line Balancing in Apparel

Manufacturing, FIBRES & TEXTILES in Eastern Europe Vol. 17, No. 4 (75),

pp.68-71.

12. Labor Management in Development Journal, 2001, Vol.2 Number 7 P.5.

13. AsmaraSoJonesSeptember 10, 2013The Most Famous Statement T-Shirts

http://textilelearner.blogspot.com/2013/09/.html

14. Stuart D, 2011. Calculation of SAM Through Time Study, http://www.onlineclothingstudy.com/2011/02/how-to-calculate-sam-of-garment.html

38


4.4 APPENDIX

1. SMV for shoulder joining



= [13.09/(60 x 80/100)] + Allowance%

= 0.272 + [(10 x 0.272)/100]

= 0.272+0.0272

= 0.30 Minute

2. SMV for over locking of lining



= [10.90/(60 x 80/100)] + Allowance%

= 0.227 + [(10 x 0.227)/100]

= 0.227+0.0227

= 0.25 Minute

3. SMV for piping



= [13.09/(60 x 80/100)] + Allowance%

= 0.272 + [(10 x 0.272)/100]

= 0.272+0.0272

= 0.30 Minute

4. SMV for neck joining



= [15.27/(60 x 80/100)] + Allowance%

= 0.318 + [(10 x 0.318)/100]

= 0.318+0.0318

= 0.35 Minute

39


5. SMV for neck overclocking



= [13.09/(60 x 80/100)] + Allowance%

= 0.272 + [(10 x 0.272)/100]

= 0.272+0.0272

= 0.30 Minute

6. SMV for sleeve hem



= [13.96/(60 x 80/100)] + Allowance%

= 0.29 + [(10 x 0.29)/100]

= 0.29+0.029

= 0.32 Minute

7. SMV for sleeve joining



= [26.18/(60 x 80/100)] + Allowance%

= 0.545 + [(10 x 0.545)/100]

= 0.545+0.0545

= 0.60 Minute

8. SMV for side joining



= [34.90/(60 x 80/100)] + Allowance%

= 0.727 + [(10 x 0.727)/100]

= 0.727+0.0727

= 0.80 Minute

9. SMV for side top stitch

40




= [26.18/(60 x 80/100)] + Allowance%

= 0.545 + [(10 x 0.545)/100]

= 0.545+0.0545

= 0.60 Minute

10. SMV for side tuck cuff



= [26.18/(60 x 80/100)] + Allowance%

= 0.545 + [(10 x 0.545)/100]

= 0.545+0.0545

= 0.60 Minute

11. SMV for neck top stitch



= [15.27/(60 x 80/100)] + Allowance%

= 0.318 + [(10 x 0.318)/100]

= 0.318+0.0318

= 0.35 Minute

12. SMV for bottom hem



= [15.27/(60 x 80/100)] + Allowance%

= 0.318 + [(10 x 0.318)/100]

= 0.318+0.0318

= 0.35 Minute

41

calculation of standard minute value of t shirt

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