DBL Group

Industrial Attachment Report

Submitted To A.K.M Sajedul Arefin Khan Asst. Manager-Planning

Zaheed Bin Rahman Student no. 0608018 Department of Industrial Production and Engineering BUET2/24/2011

Yarn spinningMatin Spinning Mills Limited has been visited for inspecting yarn production.

Technical Overview

Machined Used:

a) Blow Room: 1. Uni Flock A-112. Uni Clean B-113. Uni Mix B-704. Uni Flex B-605. Vision Shield (Jossi)6. Condenser A-21

b) Carding: 1. Rieter C-60

c) Breaker Drawing: 1. Rieter SBD-15

d) Lap Former: 1. Rieter E-32

e) Comber: 1. Rieter E-65

f) Simplex: 1. Toyota FL-100

g) Ring Frame: 1. Toyota RX-240

h) Winding: 1. Murata 21C

i) Heat Setting: 1. Xorala

Process Layout of Blow Room

Removing compressed mass of raw fiber from the bale and detecting metals in UNI FLOCK machine

Removing trash and preparing the fiber for spinning into yarn in UNI CLEAN machine

Mixing of fibers of different staple length in Uni Mix machine

Fine betting done in Uni Flex machine

Removing colored trash in Vision Shield

Condensing raw cotton

Raw Cotton (Bale)

Card Mat

CardingCard Mat Card Sliver

Card Process Layout

Breaker Drawing

Finisher Drawing

Simplex

Ring Frame

Winding

Heat Setting

Packing

Sliver

Sliver

Sliver

Roving

Yarn (Ring Cops)

Yarn (Cone)

Sliver

Sliver

Roving

Yarn (Ring Cops)

Yarn (Cone)

Yarn (Cone)

Yarn (Cone) Yarn (Bag)

Input Process Output

Flow Chart of Comb Process

Breaker Drawing

Lap Former

Comber

Finisher Drawing

Simplex

Ring Frame

Winding

Heat Setting

Packing

Sliver

Sliver

Comber Lap

Comb Sliver

Comb Sliver

Roving

Yarn (Ring Cops)

Yarn (Cone)

Yarn (Cone)

Sliver

Comber Lap

Comb sliver

Comb Sliver

Roving

Yarn (Ring Cops)

Yarn (Cone)

Yarn (Cone)

Yarn (Bag)

Input Process Output

Functions of Different Machines

Blow Room:

There are six machines for blending, opening and cleaning.

Uni Flock:

The compressed mass of raw fiber is removed from the bail. Fine particles of metal are detected in the metal detector.

Uni Clean:

Removes trash such as trash dirt, leaves, burr and any remaining seeds.

Prepare the fiber for spinning into Yarn.

Uni Mix:

Fibers of different staple length are mixed here.

Uni Flex:

Waste products are separated.

Vision Shield: It is used to separate colored trash.

Condenser: It condenses the raw cotton into Card Mat.

Description of different Processes

Carding :

Initial process of arranging the fiber in a parallel fashion is known as carding and is done on carding machine.

The lap is passed through a beater section and drawn on a rapidly revolving cylinder covered with very fine hooks or wire brushes.

A moving belt of wire brushes slowly moves concentrically above this cylinder.

As the cylinder rotates the cotton is pulled by the cylinder through the small gap under the brushes.

The teasing action removes the remaining trash, disentangles the fibers and arranges them in a relatively parallel manner in the form of a thin web.

This web is drawn through a funnel-shaped device that molds it into a rope like mass called card sliver.

Breaker Drawing:

Combines several slivers. Eliminate irregularities that would cause too much variation if

slivers were put through single. Slivers passed through several pairs of rollers, each

advanced set of rollers, revolve at progressively faster speed.

This action pulls the staple lengthwise over each other, thereby produces longer and thinner slivers.

Uni- Lap:

After carding the sliver is turned into lap form in Uni-Lap machine.

Combing:

Combed sliver produces a smoother and more even yarn. Short fibers called noils are combed out and completely

separated from longer fibers. Operations eliminate as much as 25% of the original card

sliver. Produces consumer goods with better quality.

Finisher Drawing: The purpose of this process is to measure the sliver thickness variations and then to continuously alter the draft accordingly so that more draft is applied to thick places with the result that the sliver delivery is less irregular than it otherwise would have been.

It contribute to,

Better productive efficiency Fewer end-breakage in subsequent processes Less waste and Constant process conditions.

Simplex:

After several drawing operations the fiber passes through simplex process and the output is roving.

Slight twist is given. The diameter is reduced. Gain some tensile strength.

Ring Frame:

Roving is fed in ring frame and the output is yarn.

Winding:

The yarns are further winded on cone from the ring frame. Only the good quality products pass.

Heat Setting:

To make the twist permanent, steam is passed through the yarn.

Moisture is absorbed through yarn.

Packing: Finally the yarn is ready to export or weaving.

Roving Draft Yarn

Fabric knitting

In fabric knitting department following units have been inspected.

1) Jinnat apparels limited

2) Jinnat knitting limited

3) Jinnat fashion limited

4) Matin knitting limited

Products of knitting section:

1) Single Jercy

2) Fleece

-2 thread fleece

-3 thread fleece

3) Rib

-1/1 rib

-2/1 rib

-4/2 rib

- Half feeder Lycra rib

- Full feeder Lycra rib

4) Interlock

- Plane interlock

- Drop needle interlock

- Half feeder interlock

- Full feeder interlock

5) Single lacost

6) Double lacost

7) Single pique

8) Double pique

Some important terms regarding knitting machine:

Sinker: Keep the fabric from lifting up.

Feeder: Delivers constant rate of yarn to the needles.

Cylinder: Cylinder is placed on the centre of the machine and it rotates.

Cam box: Cams are fixed with the cam box. It regulates the needles movement. There are three types of cams which are used in the knitting machine,

- Knit cam

- Tuck cam

- Miss cam

Gauge: It refers to the number of needles per inch.

Course: It refers to the rows of loops across the width of the fabric. Every feeder knits each course.

Wales: Vertical column of needle loops are known as Wales. Number of Wales determines the width of the fabric.

Stitch length: Length of yarn in a loop or stitch.

GSM: GSM means Gram per Square meter.

Production process flow chart:

Knitting defects:

1) Holes: Caused by broken needle.

2) Needle line: Caused by bent needle forming distorted stitches.

3) Miss yarn: Occurs in warp knit. Results from wrong fiber yarn placed on wrap.

4) Oil stains spot: Dirty oily looking spot on the yarn.

Yarn Book Machine SelectWarehousing

Quality CheckBulk Production Machine Setting

Warehousing

5) Lycra missing:

6) Fly yarn: Caused by yarn of another fabric.

7) Black spot: Unusual black spot on the fabric surface.

8) Hairiness: Hairy surface of the fabric.

9) Knots: Caused by tying spools of yarn together.

10) Drop stitches: Results from malfunctioning needle or jack. It will appear as holes or missing stitches.

Quality checking of fabric:

4- Point system is used in checking the quality of fabric. It involves considering size of the defect.100% inspection is done. If

0 < Size of the defect < 3 inch 1 point penalty

3< Size of the defect <6 inch 2 point penalty

6< Size of the defect <9 inch 3 point penalty

9 inch < Size of the defect 4 point penalty

If the fabric is marked between 0 - 20 points then it is considered A- grade and if it is marked between 20 - 30 points then it is considered B- grade and if it is above 30 points then it is rejected.

Process Flow Chart of Dyeing & Finishing

(For Special Fabrics)

Receiving Gray fabrics from knitting section

Batching

Dyeinga) Scouringb) Dyeingc) Washingd) Softening

Slitting

Grey Heat setting

(Stentering)

Back sewing

Tubular Finish Open Finish

Dewatering & Detwisting

Drying

Compacting

Slitting

Stentering with weft straightener

Special Finish Normal Finish

Suedding Brushing

Stentering with weft straightener

Open Compacting

Quality Inspection

PackingReady for Delivery to

Garments

Explanation of Process Flow Chart:

At first Grey fabrics are received from knitting section to the storage facility of Dyeing department. Grey fabrics are stored in the storage according to buyer, order, dia (width of fabric) and color. All storage information is kept in stock card. In the batching section production manager creates a dyeing plan. According to the planning batching section releases a batch card to send order for dyeing. When a lot is released from store it is sent to turning machine. Turning machine is used to remove dust from the fabric using a blast of air. After turning fabrics are sent to the dyeing machine.

Dyeing: In the dyeing machine the first step is scouring. Scouring is a process of further dust removing from fabrics. Then bleaching is done which is a process of pretreatment of fabrics using oil & wax. Enzyme is also applied to the fabrics to destroy the surface fiber or to convert tubular fiber into open fiber. Then color and dyeing auxiliary items are applied. At last cooling and washing of the fabrics is done.

Finishing: There are two types of finishing process.

a) Tubular Finishb) Open Finish

Tubular Finish: First step is dewatering & detwisting. In the dewatering process fabrics are washed using only water and then sent to the chemical bath for softening. Then water is removed from the fabric using compaction. Almost 60% water is removed in this process. Generally after dyeing process surface of the fabric becomes rough. To remove roughness softening is done using various chemical softeners in the chemical bath. Before entering into the dewatering machine fabrics are entwisted to regain its normal shape and to perform further operations smoothly. Then the next step is drying. In the dryer machine change of GSM and shrinkage of fabric takes place and 35% water is removed. Then fabrics are sent for compacting where compaction and further GSM change occurs. During compaction 7% water remains in the fabric to keep strength. After compaction inspection of the fabrics is carried out.

Open Finish: At first slitting is done where fabrics are cut through the needle line to convert tubular fabric into open fabric. Then stentering is done which is a process of drying wet fabric. Then normal finishing or special finishing is applied according to buyer requirements.

Special Finish: First step is suedding and brushing. Suedding is a process of converting the fabric fiber into pile form. It can be done on any type of fabric. Brushing is a process of raising the loop of the fabric fiber. It can be done only on fleece fabric. After brushing is done, shearing can also be done according to buyer requirements. Shearing is a process of cutting raised loop fiber according to required size of the loop. Then stentering is done to dry the fabric and then sent for open compacting. Open compacting is a calendaring process where lengthwise strain obtained in the previous process is recovered.

Then quality inspections are carried out and dyed fabrics are sent for packing. After packing dyed fabrics become ready for delivery to garments.

Above processes are for normal fabrics. But in case of special fabrics some additional steps are carried out along with regular processes. At first slitting is done which is a process of cutting fabrics through the needle line. Then Grey heat setting and stentering is done. Grey heat setting gives the fabric dimensional stability and stentering adjusts dia (width of fabric).

Importance of steam: Steam is important during finishing because it makes the fabric suitable for various processes.

Capacity:

Production capacity: Total production capacity is 35 tons per day. But actual capacity is 30 tons per day.

Storage capacity: Total storage capacity is 650 ton.

Process Flow layout of sample section

File

Pattern making

Sample cutting

Sample making

Checking by QC

Sent to buyer

Sample is tagged & Send back

Improved sample sent to buyer

Sample ok (approval)

Production starts

Explanation of Process Flow Chart:

At first buyer send a file consists of detailed design, size of the product to the marketing department. Marketing department calculate total price of the product and the calculation is based on the file. Then the file is sent to the garments sample production department to make sample. Sample production department make a pattern based on the file using hard paper. This hard paper or pattern is then used for sample cutting. In this process this pattern is placed on the fabric and the fabric is cut by scissors. After cutting sample is then made in sewing machine. Finished sample is checked in the quality control section where sample is compared to the given size and design of the product. Finished sample is also ironed and sent for packaging. Then sample is sent to the buyer. Buyer checks the sample and tags it for necessary adjustment. Sample is made again according to the necessary adjustments. If the sample is ok then buyer approves it for production. Then the production starts.

Some Terminology regarding sample making:

Spec sheet: It is a measurement sheet consists of all sizes of the product.

Pattern making: It is a process of creating a base size sample based on file.

Grading: It is a process of creating another pattern of different sizes considering the base size sample.

Styling: Design of the product.

Types of sewing machines used:

1. Plane machine2. Over lock machine3. Flat lock machine4. Feed of the arm5. Pico ting machine 6. Button stitch7. Hole stitch8. Snap button machine9. Piping cutter10. P. M. machine

Quality Checking: This process consists of the following steps,

1) Sample is checked with file.2) Sewing of the sample is checked.3) Styling or design of the sample is checked.

Capacity of sample production department:

Average capacity of the sample production department is 150 pieces per day. Number of sewing person in the department is 43 and the target sample production per person is 5 pieces per day. But the actual production per person is 3 pieces per day.

Process Flow Layout of Cutting Room

Receive marker along with block pattern/Copy of block pattern

Cross check, marker & block pattern by concern cutting & QC supervisor

Not OK

Need rectify

Check

OK

Go for cutting

Proceed sample (sample make by line chief/supervisor)

Finish sample

Hand over to QC along with report (Report make by sample maker, with his findings during making sample)

QC will check details

Prepare risk analysis report along with report

Sample review meeting for correction

Make report

Check pattern, cutting, marker & confirm (cutting supervisor & QC supervisor)

Bulk cutting

Explanation of Process Flow Layout:

At first cutting room management receives marker along with block pattern from marketing department. After receiving marker & block pattern quality control or cutting supervisor check it (in CAD room). If the marker is ok then they go for cutting. If the marker is not ok then it need to be rectified and checked. After check line chief or supervisor proceed for making sample. During making sample a report is made concerning the sample. When sample is finished line chief handover it to the quality control along with report. Quality control check details of the sample and prepares risk analysis report along with previous report. A review meeting is arranged if there is any need for correction. A report is made based on sample review meeting. Then cutting supervisor and quality control supervisor check pattern, cutting and marker and confirm and go for bulk cutting.

Fabric relaxation: After finishing fabric are kept in normal condition for 8 to 10 hours to regain its normal elasticity. This is done to prevent size deformation. It can be done on many fabrics to avoid shrinkage problem.

Auto spreading: Before cutting fabrics need to be spread over the table. It can be done manually or by automatic machine. In the cutting room Gerber machine is used to spread the fabrics.

Scissor cutting: This kind of cutting is used to cut small amount of fabric.

Bulk cutting: This kind of cutting is used to cut large amount of fabric.

Bundling: After cutting fabric pieces of a single style or design is bundled together for sewing.

Cutting capacity:

Total capacity of the cutting room is 60000 pieces per day. Production is carried out for 1 shift.

Process Flow Layout of Printing & Packaging:

Artwork/Technical sheet received from buyer

Marketing department

Printing & Packaging department

Design development by Photoshop & Illustrator

Printing on Tracing Paper

Mesh Fabric Binding

Applying photo emulsion Coating on Mesh Fabric

Screen Exposure to Light

Screen Washing by Water Jet

Print

Explanation of Process Layout:

At first artwork or technical sheet consisting of the design to be printed is received from buyer in the marketing department. Then the artwork is sent to the printing & packaging department where further development of the design is carried out in design software like Photoshop & Illustrator. After the design is developed it is printed on tracing paper. Then the tracing paper is attached on a frame using glue which is known as mesh fabric binding. Then a special kind of photo emulsion coating is applied on the mesh fabric and exposed to light for 10 minutes. Exposure to light makes the photo emulsion coating weak in areas where design is printed. After exposure to light water jet is used for washing the screen. At this time weaken photo emulsion coating is broken and the tracing paper is ready to be used for print.

Printing Types:

1. Pigment print2. Rubber print3. Discharge print4. Flock print5. Foil print6. Crack print7. Plastisol print8. General print9. Burn out print10. Glitter print11. Puff print12. Glow in the dark print13. Sueted print14. High density print15. Photo print16. Glossy print17. Metallic print18. Stud print

Printing Problems:

1. Print size mistake2. Print position mistake3. Print color mistake4. Print registration problem5. Color stain problem6. Color shading problem

Types of Quality Testing:

1. Color fastness to washing2. Color fastness to water3. Color fastness to rubbing4. Color fastness to perspiration5. Color fastness to saliva

Capacity of Printing & Packaging department:

Total capacity is 100000 to 125000 pieces per day.

Process Flow Layout of Finishing & Packing

Receive sewing output

Remove thread

Bundling

Ironing

QC check

Get up check

Size measurement

Price hangtag

Get up iron QC check

Metal detectorQC check

Folding

Poly

Packing

Spot clean QC check

Get up iron

Explanation of Process Flow Layout:

At first output of the sewing process is received from sewing output table according to color & size. Then thread is removed from the sewing output in thread machine and bundled together according to size & color. Then sewing output is ironed and sent to quality control check. Get up check is also done for extra checking. Then size measurement is taken to check whether it meets buyer requirements. Then price hang-tag is attached to sewing output and goes for Get up iron. Again quality check is done and folding of sewing output is completed. Sometimes due to handling by hand creates spot in the white fabric. If spot is created it is cleaned by soap, jet powder & acetone. Then QC check and get up iron is also done. Then sewing output is inserted into polythene bag and ready for packing in carton. Metal detector test is also carried out but it depends on buyer.

Assorted packing:

1. Solid color-Solid size2. Assorted color-Sold size3. Solid color-Assorted size

Folding types:

1. Half folding2. Flat folding3. Boat folding

Accessories:

1. Price hangtag2. Price sticker3. Lock pin4. Tag pin5. Band roll6. Bio cotton7. Size sticker8. Barcode sticker9. Country sticker10.Shipping mark11. Gum tape

CBM calculation:

If 1000 carton is used and carton length-40 cm, carton width-40, carton height-20 cm then cbm = 40×40×20×1000=32,000,000=32 cbm

Capacity:

Total capacity is 12000 to 15000 pieces per day.

Work–study:

Work-study is the systematic examination of the methods of carrying activities so as to improve the effective use of resources and to set up standards of performance for the activities being carried out.

Work-study

Method study Work measurement

Work place engineering Time study

Motion economy G.S.D

Sew easy

Capacity study

Historical data

Minimum work place Analytical estimating

Maximum work place

Bottleneck:

Which are holding up production operations, or a lengthy operation, that consumes a great amount of time.

A bottleneck is the operation in any team that has the lowest capacity of production.

Reasons of bottleneck:

A bottleneck may be raised in the line for the following reasons,

1) If the said operators has more work content than other operators.2) If the operator is unskilled or semi skilled in respect to the operation.3) If there happens quality fault in the operation.4) If two or various types (color) of thread are used in the same machine.5) If there is any problem in machinery purpose.

Formula of Operation Capacity graph:

Capacity/Hr = (60/Capacity Total Avg. Time) * Total Manpower

Capacity Achievable = Capacity per Hour * Balance %

Performance = (SMV / Capacity Total time) * 100

Balance = Basic Pitch Time / Bottleneck Time

Improvement % = 1- (Production per Hour / Capacity per Hour)

BPT = Capacity Total Avg. Time / Total Use Worker

UCL = BPT * 120 %

LCL = BPT * 80 %

Work Study Formula:

Target / Hr = Total Worker * (60 / SMV) * 73 %

Efficiency = (Earn Hour / Available Hour) * 100

Earn Hour = (Total Production * SMV) / 60

Available Hour = Total Worker * Total Working Hour

Performance = Earn Hour / (Available Hour – Total off Hour) * 100

Target Achieve Efficiency = (Total Production / Total Target) * 100

Basic Time = (Observed Time * Rating) / Standard Rating

Observed Time = Time recorded by qualified work study officer by observing a regular worker while he/she is doing a task.

Standard Rating = The pace at which a qualified worker perform a task, Standard Rating=100

Allowance Time = 30% of basic time (Personal allowance, Recovery allowance, Technical allowance, Bundle handling allowance)

Standard Minute Value (SMV) = Basic Time + Allowance Time

Sample Calculation:

Here the first operation is Front Rise & Back Rise Match.

For this operation, SMV = .20 min.

SMV Target = 300 pieces/hour

After study, 10 Cycle Time = 2.12 min.

10 Cycle Time × 1.7 = 2+ (.12×1.7) = 2.20

Average = 2.20 / 10 = .22

30 % Allowance = .22 × .3 = .066 = .07

Total Time = .22 + .07 = .29

Capacity = 60 / Total Time = 60 / .29 = 206.896 = 207 pieces/hr

Performance = (SMV / Total Time)*100 %

= (.20 / .29)*100 % = 69 %

Working Flow Chart (WS)

Received Order List from Merchandiser

Received Sample

Do Process Breakdown

Calculate SMV

Provide SMV to Marketing & Planning

Making Paper Layout

Arrange PP Meeting

Follow-up M/C Layout during Issue

Do Time Study & Line Graph

Help Re-Balance the Line & Finalize SMV on Line by Time Study

Do efficiency & Others Report

Merchandising Department

Factory

Double Confirm & Prove Work Process Along With Factory/In-charge

Send Report to All Concern

Along With Floor In-Charge

Along With Concern Department

Within 2 Days from Issue

Prepare Machine & Work Flow Chart