Parameters of finishing machine

Achieving finishing target of knit fabric means to achieve the finished fabric with all the quality or parameters that is required by the customer..  In case of knit fabric, target qual

FINISING PRAMETERS

Name : MAZADUL HASAN SHESHIR

ID: 2010000400008

Batch: 13th Batch (Session 2009-2013) Department: Wet Processing Technology Email: mazadulhasan@yahoo.com (FB) Blog: www Textilelab.blogspot.com

Southeast University,Bangladesh

Department of Textile Engineering

PREPARED BY © right

Knit fabric Finishing

The term finishing, in a broad sense it covers all the processes of making the fabric good looking, good hand feeling, luster and of course for buyer requirement It is done after dying and before delivery to market Various types of parameters are controlled during finishing section considering buyer requirement The term also includes bleaching, dyeing, mercerizing etc But normally the term is restricted to the final stage in the sequence

of treatment of Knit fabrics after bleaching and dyeing However, fabrics which are neither bleached nor dyed are also finished.

The aim of finishing is to render textile goods fit for their purpose or end use Besides that, finishing can be done for achieving the following purposes-

a) To improve fabric attractiveness.

- By modification of fabric appearance(optical brightening),

-By altering fabric handle (Softening, Stiffening)

-Control of fabric dimension (Sanforising, Compacting)

b) To improve service ability.

-Protection of fabric (Flame proofing, Water proofing)

-Improved performance (Water repellency, Raising)

-Easy care properties (Resin finish, Crease recovery)

Objects of finishing:

Achieving finishing target of knit fabric means to achieve the finished fabric with all the quality or parameters that is required by the customer

 In case of knit fabric, target quality refers to the shade, GSM, shrinkage, spirality, color fastness etc When order is placed, at first fabric structure, GSM, shade is considered Depending on the parameters yarn count, m/c gauge, stitch length, machine dia, yarn type are selected all those factors are related with target quality

 Grey fabric gsm should be lower than finished gsm In case of knitting fabric at least 15% weight will increase during wet processing

 Grey gsm will depend on the shade percentage, lycra %, type of yarn used and type of finishing pequired for that particular fabric For light shade stitch length will be more than deep shade

 In case of spirality, it will depend on the yarn count, compactness, feeder no of the knitting machine If count (Ne) is high, compactness of the fabric is more and feeder

no of the m/c is lower than fabric spirality and shrinkage will be less

Finishing & Finishing Target:

 Yarn count and m/c gauge are related to each other and if those two factors are not matched then faults will be occurred on the fabric For example, 20’s for 20G/18G, 30’s for 24G, 40’s/28G will yield lower spirality and shrinkage

 In case of wet processing, shade must be developed in the dyeing laboratory and should be approved by the buyer The recipe that is developed in lab is used by reducing in quantity for bulk production Because dye pick up percentage is always high in dyeing m/c

 Shade should be kept in deeper condition before dropping of dye liquor from dyeing m/c because shade could be lighter during soaping In case of finishing process, padder pressure, temperature, fabric speed, chemicals and finishing line should be determine by considering the finishing target because, all those factors may affect fabric shade

 When fabric is unloaded from m/c water content is about 200% in case of knit fabric Thus hydro-extractor, de-watering m/c are used before drying the fabric Otherwise heat consumption for drying process will be huge and that is not cost effective In this section finishing chemicals can be applied to the fabric

Finishing & Finishing Target:

 Drying machine is used to evaporate water remaining in the fabric after watering process and to obtain fully dried fabric Fabric dia will reduce during relax drying process and tube fabric is finished in this machine

 Thus tubular fabric dia should be kept more than the required finished dia in watering machine This dia will be reduced in drying machine After that tube compactor is finally used to achieve target quality of the fabric gsm can be controlled up to 10%

de- But in case of open line, stenter machine is used, which may control most of the parameters in knit fabric But fabric should be in open form Thus open squeezer

is used to slitting the fabric Then the fabric is feed on stenter where chemicals can also be applied Fabric shrinkage, spirality, Gsm, shade, bowing effect, slanting etc can be controlled by stenter m/c Maximum 20% gsm can be controlled by stenter m/c

 Fabric shade can be controlled by maintaining temp if shade is dark then temp should be high and 15-20% light shade can be obtained

Finishing & Finishing Target:

 If shade is light in fabric then temp should be lowered and silicon softener is used in large quantity.Then the fabric is finally finished with open compactor m/c Maximun 14% gsm of the fabric can be controlled

 If ultra-soft fabric is required by the buyer, then gsm of the fabric should be kept

at least 5% more after finishing process Softening action is done on the back side of the fabric and the fabric is again finished on stenter m/c

 In case of brushing, the back side of the fabric is brushed Loops of the fleece fabric are brushed Fabric may feed on the m/c for 5-8 times until the target brushing action is achieved

 After all those operations, quality control process of the fabric is done in online and off-line process In online process gsm, shade, shade variation, hole patta, bowing, slanting, oil mark, chemical spot etc are checked and graded with 4 points system In off-line QC shrinkage, spirality, gsm, color fastness, wash fastness etc are done which are required by the buyer

Finishing & Finishing Target:

 Sometimes problem can appear such as shrinkage, spirality, gsm of the fabric which cannot be controlled by those finishing process In this case fabric is wetted and tumble dried to overcome those problems

 By this process, sample fabric is finished at first then required tests are done on the fabric Sometimes it is not possible to control shrinkage, gsm, spirality, and other knitting faults due to knitting m/c and yarn In this situation, the knitting department should take necessary actions to overcome those problems If any faults or quality problem is appeared due to dyeing or finishing the fabric should

be reprocessed, such as re-dyeing, topping, stripping are done and finished again But target should be to finish the fabric without re-processing

 Above all those factors, target finished date must not exceed to finish the fabric

If the fabric is achieve with all the required quality within the target finished date then that will be said that we have achieved the finishing target of knit fabric for a particular batch

Finishing & Finishing Target:

PRODUCTION PARAMETER

OF

STENTER

STANDARD OPERATING PARAMETER FOR DIFFERENT FABRIC IN STENTER

Fabric Type GSM Dia (“) Temperature (*c) Feed(%) Over Pressue Padder Speed (rpm) Blower rpm

Single jersey 115-150 2”+ 110-140 40-45% 2 bar 30-35 1100-1300Single jersey 160-220 2”+ 120-170 40-45% 2.5 bar 25-30 1200-1400Lycra Single

jersey 160-200 4”+ 130-160 50% 2 bar 25-30 1200-1400Lycra Single

jersey 200-250 4”+ 140-160 50% 2 bar 24-28 1200-1400Pique 160-200 3”+ 130-160 40-45% 1.5-2bar 25-30 1200-1400Lycra Pique 190-220 4”+ 130-160 50% 2 bar 20-25 1200-1400Fleece/Terry 260-300 4”+ 140-170 40-45% 2 bar 20-25 1300-14001x1 Rib 160-220 2”+ 130-160 45% 2 bar 24-28 1300-14002x2 Rib 190-220 2”+ 140-160 45% 2 bar 20-25 1200-1400Interlock 190-220 3”+ 130-160 50% 2 bar 20-25 1200-1400

Relation between yarn count, fabric type, stitch length and finished GSM:

For Single

jersey-FINISHED GSM COUNT FINISHED DIA

140 30/1 Machine dia=Finished dia

160 26/1 Machine dia+1=Finished dia

180 24/1 Machine dia+2=Finished dia

200 20/1 Machine dia+3=Finished dia

220 18/1 Machine dia+5=Finished dia

For Plain

Relation between yarn count, fabric type, stitch length and finished GSM:

If the fabric is to be Enzyme washed, the stitch length should be kept (10%) less than the normal range Because, enzyme wash reduces the total weight of the fabric by removing the floating fibre and hairy fibre

For light color, the finished GSM varies near about 15-20% from grey GSM For average color, the finished GSM varies 20-25%

For dark color, grey GSM is kept less (i.e the stitch-length is large) because take up%

of dark color is more and the weight of dyed fabric will be increased

If the GSM varies 25-30%, it is not only necessary to control the VDQ pulley dia but also yarn tension & take up roller

Fabric Type Overfeed % Temperature0C Speed

(m/min) (%) Inch Stretch

LightColor ColorDeep

Single Jersey 30 % to 45% 150-1550C 160-1650C 25~28 Depend on

fabric G.S.M

Single Lacoste 30 % to 42% 150-1600C 160-1650C 22~26

Depend on fabric G.S.M

Polo Pique 30% to 6405% 150-1600C 160-1650C 20~25 Depend on

fabric G.S.M

Interlock 30 % to 40% 1650C 165-1700C 22~24 Depend on

fabric G.S.M

Parameters for cotton Fabric:

GSM COLOR SET TEMP HEAT DELIVERY DIA OVER FEED m/min SPEED

AFTER HEAT SET GSM

LESS FROM REQUIRED GSM

190- 200

White & ligh 185C +15% 40/18/25 20 150 20-25Average 185C +15% 40/18/25 20 145 20-25R/black 185C +15% 30/15/20 20 130 25

160-170

White & ligh 185C +15% 40/18/25 20 130 20-25Average 185C +15% 40/18/25 20 125 20-25R/black 190C +15% 30/15/20 20 120 25

150

White & ligh 190C +15% 40/18/25 20 100 20-25Average 190C +15% 40/18/25 20 100 20-25R/black 190C +15% 30/15/20 20 100 25

Procedure for Heat set for Lycra s/j fabric:

Dia Control:

Fabric Dia(Increase)

Single jersey 1.5 – 2 ) inch +

Rib fabric 2 – 2.5 inch +

Interlock 3 – 3.5 inch +

Pique 3 – 3.5 inch +

Dia is controlled by dia controlling meter scale.

1 -If any fault, GSM of the fabric is reduced then to increase the GSM of the fabric dia will have to be reduced (2 – 3) inch.

2 -If Over feed speed is more then Dia of the fabric will be more.

3 -If Over feed speed is less then Dia of the fabric will be less.

4 -If length is more then width of the fabric is reduced.

5 -If length is less then width of the fabric is more.

N.B: Fabric speed is controlled on the fabric dia Here, Dia less or More fully

depends on yarn count and buyer order Dia is done less or more by using expander rod.

Procedure for Heat set for Lycra s/j fabric:

GSM COLOR SET TEMP HEAT DELIVERY DIA OVER FEED m/min SPEED

AFTER HEAT SET GSM

LESS FROM REQUIRED GSM

240- 230

White& light 190C +15% 40/18/25 20 185 20-25Average 190C +15% 40/18/25 20 180 20-25

210- 220

White & ligh 180C +15% 40/18/25 20 165 20-25Average 180C +15% 40/18/25 20 160 20-25R/black 185 C +15% 30/15/20 20 140 25

Rules for heat set fabric:

1 Temp constant(give in heat set process)

2 Speed always constant

3 Over feed

A.For white & average color

i Standard: 40/18/25

ii Minimum: 30/15/20 iii Maximum: 50/25/25

B For black color

iv.Standard: 30/15/20 v.Minimum: 20/12/18 vi.Maximum: 50/25/25

4 Stretch:

i Maximum: 35% to 40%

ii Minimum: 18%

5 After heat set fabric dia (delivery)

i.Maximum: given in heat set procedureii.Minimum: 14% of m/c dia

6 GSM

i White color: required GSM (less 50 to 55)

ii Average color: required GSM (less 60 to 65)iii Black color: required GSM (less 75 to 80)

PRODUCTION PARAMETER

OF

COMPACTOR

For different type of fabric speed and compaction ( TUBE TEX ):

Fabric Type Speed ( r.p.m ) Compaction

WORKING PARAMETER OF COMPACTOR

Fabric type Colour Speed Over Feed Temperature Blanket

Pressure Teflon Pressure

Single

jersey

White Colour

15-18 15-18

25-30 25-30

90-110 110-120 1.5-2bar 36psiPique

(s/j,d/j)

White Colour

15-18 15-18

30-35 30-35

100 110-120 1.5-2bar 36psi

Lycra s/j White

Colour

12-16 12-16

Full over feed

100-110 100-120 1.5-2bar 36psi

1x1 Rib White

Colour

15-20 15-20

20-30 20-30

100 110-120 1.5-2bar 36psi

2x2 Rib White

Colour

15 15

12-25-30 25-30

100 110-120 1.5-2bar 36psi

Interlock White

Colour

12-16 12-16

Full over feed

100 110-120 1.5-2bar 36psi

Shrinkage Tolerance of Different Fabric:

Overfeed % Up Setup for Lafer compacting Machine:

Overfeed % Up for Lycra Single Jersey : 60 Overfeed % Up for Single Jersey : 35/40.

Overfeed % Up for Lacost fabric : 35/40 Overfeed % Up for Rib fabric : 20/22 Overfeed % Up for CVC fabric : 45

Fabric type Colour (m/min) Speed Over Feed

(%) Temperature (degree C)

Blanket Pressure

Teflon Pressure

Stretch (%)

Single

jersey

White Colour 15-18 15-18 25-30 25-

30

90-110 110-

35

100 110-120 1.5-2bar 36psi As required

Lycra s/j White

Colour 12-16 12-16 over Full

feed

100-110 100-120 1.5-2bar 36psi As required

110-120 1.5-2bar 36psi As required

(Blanket type)

Type of Fabric Padder Pressure Over feed

Parameters used for different types of fabric:

Fabric Req GSM Finish GSM R F B Temperatur e m/min Speed Over feed

PRODUCTION PARAMETER

OF

DRYER

Fabric Type Overfeed

% Temperature0C Speed (m/min) Folder Speed

Low G.S.M

Single Jersey 30 % to-40% 150-1600C 130-1500C 15-20 20-25 2~3 As

Required Single

2~3

As Required

PARAMETERS USED FOR DIFFERENT CONSTRUCTED FABRIC

For cotton fabric:

Fabric Type Temp

(oC)

Over feed (%)

Vibration Ext Temp

Checking parameters:

1 Overfeed ( %) : It depends on fabric structure & GSM

2 Temperature: It depends on color & GSM.( normally for single jersey -1600C, for high GSM, like-fleece, it may be 2500C )

3 Speed: It depends on fabric GSM For higher GSM, lower the speed.

M/C set up for Ruckh relax dryer:

Temperature setting 100c- 120c for white shade

120c-130c for light shade 130c-140c for Dark shade 150c-170c for curing

Blower fan setting Auto

Exhaust fan setting Auto

M/C Speed 3-35 m/min Depends on quality of fabric Over feed 0-40% depends on fabric construction Width of expreader setting 45-114 cm: Depends on the required

width of fabric.

PRODUCTION PARAMETER

OF

SQUEZER Or PADDER

Over feed and Padder pressure of

Squeezing Machine:

Feed roller pressure:

Fabric Type Pad pressure Speed Over Feed

PRODUCTION PARAMETER

OF

SLITTER

Over feed and Padder pressure of Slating Machine:

Fabric Type Pad pressure Speed Over Feed

Singeing:

Speed(m/min) 0-120  55-60 for cotton

 70 for PC/CVC

Potentiometer Setting (rpm) 0-150  80-90 for cotton fabric

 60-70 for CVC/PC

Burner operation mode Auto/Manual Auto

Flame height (cm) 1-8  6 for white & light shade

high

 Low – not used

 Medium – for white & light shade

 High – for medium & dark shade fabric