Problem and it's remedies in Processing

 

Problem and it's remedies in Processing

GREY ROOM

A) Thick & thin place:-

Causes                                                                                     Remedies

 1. Immature fiber.                                                               1. Selection of raw material

 2. Staple length.                                                                 2. Mature fibre.

 3. Neps.                                                                              3. Good staple length.

 

B) Weft bar:-

Causes                                                                                    Remedies

 1. Count variation                                                                1. Use Less variation of weft count.

 2. Density of pick more.                                                      2. Required density of weft.

 

C) End & Pick missing:-

Causes                                                                                    Remedies

1.Warp stop motion not working on loom at                        1. Use warp stop motion as per break.

    warp break

2. Moving empty shuttle.                                                      2. New extra thread joining

3. Breakage of weft thread                                                   3.Mending.

                                                                            

 

SHEARING & CROPPING

 

A) Cut or holes damage to fabrics:-

Causes                                                                                Remedies

1. Presence of metallic particle on fabric.                            1. Use magnetic metal detector in feeding device.

2. Due to abrading action.                                                    2. Removal of metal particle from grey fabric.

 

 SINGEING    

A) Incomplete singeing:-

Causes

1. Low flame height.                                                         1. Flame height 4”- 6”

2. fast fabric speed                                                            2. Fabric speed 90-120 m/min

3. High Moisture content                                                  3. Ensure moisture content should be 6-8%

 

B) Uneven Singeing:-

1. Change in fabric speed during singeing                       1. Maintain Uniform fabric speed throughout singeing

 

C) Thermal damage:-

1. Too slow fabric speed                                                 1.Fabric speed must be set above 60-70 m/min

2. Close distance between the fabric and                        2.6-8 mm upto 6-20 mm distance between the strength fabric                                   the burner                                                                           and the burner

 

 

 DESIZING

A) Incomplete desizing:-

1. Inappropriate desizing bath pH                                       1. Set pH of bath depend on enzyme type

                                                                                                 Malt extract 6-7.5

                                                                                                 Pancreatic 6.5-7.5

                                                                                                 Bacterial 5.5-7.5

2. Insufficient fabric pick-up                                               2.Use of wetting Agent

3. Deactivation of enzyme due to                                        3.Use of appropriate sequestering agent

     presence of metals or other

     agents contaminants

4. Inappropriate desizing bath temperature                       4.Temperature of bath must be 80-95• C.

 

B) Uneven desizing:-

1. Inappropriate bath temperature                                      1. Ensure bath temperature of bath 80-90° C

2. Non-uniform washing after                                            2.Ensure Hot wash at 95°C for 10-15min Thorough and                                           desizing                                                                               uniform washing after desizing

3. Preferential drying of outer layers of the batch              3a.Covering the batch with polythene or other suitable sheet

                                                                                            3b. Keep the batch rolling

4. Temperature variation during digestion                          4.Covering the batch with polythene or other suitable sheet

5. Foaming in the bath                                                         5.Use of appropriate defoamer

 

SCOURING

A) High residual impurities:-

1. Inadequate concentration of scouring chemicals            1.Check recipe Sodium carbonate - 2-3% owf

                                                                                             Anionic  detergent - 1-3 g/l

2. Ineffective or incompatible surfactant/wetting agent     2.Effective and compatible surfactant/wetting agent

3. Water hardness                                                                3.Use of soft water

4. Ineffective chelating agents                                            4.Effective chelating agents

 

B) Damage or loss in strength:-

1. Contamination of iron                                                    1a.Use of appropriate complexing agent

                                                                                           1b Water purification

2. Presence of air in the machine                                       2a.Exclusion of air

leading to the formation of oxycellulose                           2b.Use of mild reducing agent Bleaching

C) Uneven whiteness:-

1. Use of inappropriate surfactants                            1.Appropriate/ compatible surfactants

2. Irregular chemical feeding                                     2.Optimum chemical feeding

3. Foaming in the bath                                               3.Appropriate use of defoamer

4. Water hardness                                                       4.Soft water or use of sequestering agents

5. Condensation or water marks                                5.Optimum steaming conditions

6. Inappropriate use of defoamer                               6.Appropriate use of defoamer

 

D) Harsh handle:-

1. Silicate deposits                                                    1a.Optimum control of pH

                                                                                  1b. Use of organic stabilisers

                                                                                  1c.Thorough washing after bleaching

 

E) Resist marks:-

1. Deposits of insoluble salts of surfactants               1.Use of soft water or appropriate chelating agents

2. Redeposition of impurities                                     2a.Careful selection of scouring auxiliaries

                                                                                   2b.Thorough washing after scouring

 

F) Fiber degradation Reduction in fibre strength:-

1. Metal contaminants                                              1a.Treatment of water to remove metal contaminants

                                                                                  1b.Use of appropriate complexing agents

 

G) Low degree of whiteness:-

1. Too low bleaching pH                                           1.Ph 10-11

2.Residual sodium acetate after                                2.Thorough rinsing after Neutralization

Neutralization

3. low steaming temperature                                    3.Steaming at 90-95^C Check no leakage of steam

4. Short steaming time                                             4.Steaming 60-90min

 

MERCERIZATION

A) Low increase in luster:-

1. Dwell time                                                               1. Dwell time should be 60 sec

2...Low concentration of Caustic                                 2.Caustic concentration must be 52Tw or 26 Be

3. insufficient fabric stretching while on the frame     3a.Optimum fabric stretching while on the frame

                                                                                      3b.Use of tensioner device

 

B) Poor shrinkage control

1. insufficient fabric stretching while on the frame    1.Optimum fabric stretching while on the frame

2. Too much caustic on the fabric as                           2.Removal of excess caustic from the fabric before it comes off it                                    comes off the frame                                                   the frame

 

 

 

 

 

 

 

 

                                                                             

 

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