I. Fabric Dyeing Quality Issues
1. Seam End Marks: Dark stripes appear across the entire fabric at both ends, mainly due to excessively wide or thick seams. During winding, pressure causes water accumulation, leading to dye buildup.
Solutions: Control the seam width; make several cuts after sewing to release stress; adjust tension to prevent fabric sagging.
2. Color Difference at the Beginning and End: Inconsistent color at the beginning and end of the fabric is often caused by a high initial dye concentration followed by a decrease.
Solutions: Keep the dye guide clean; add dye in stages according to dye properties; when dyeing the same color continuously, reuse residual dye from the previous batch to balance the concentration.
3. Color Difference at the Edges (Left, Center, Right): Uneven color between the edges and the center is often caused by improper doctor blade curvature, uneven dye spraying, or tension imbalance.
Countermeasures:
Color Spots and Dotting: Adjust the fabric stretcher curvature to 4-8mm; check for nozzle blockage and optimize the reversing frequency to once every 2-3 minutes.
4. Color Spots and Dotting: Mottled or small dark spots on the fabric surface are commonly caused by insufficient dye dissolution, an insufficient liquor ratio, or temperature fluctuations.
Countermeasures: Use soft water to dissolve the dye; prepare the sizing first, then dissolve in warm water; for reactive dyes, a water temperature of 40-60℃ is recommended to avoid high-temperature hydrolysis.
5. Color Difference Between Front and Back Sides: Inconsistent color on the front and back sides or left and right sides is a typical problem of uneven penetration.
Countermeasures: Increase the liquor ratio to 1:3 or higher to enhance penetration; cover the machine with a heat-insulating cover to prevent excessive heat loss from the edges.
II. Mechanical and Operational Faults:
1. Wrinkles: Straight wrinkles in the warp direction of the fabric are caused by uneven seam ends, excessive tension, or non-level rollers.
2. Wrinkles and Dotting:Solutions: Ensure the seam ends are flat and the fabric width is even; adjust the tension appropriately and clean the stainless steel rollers regularly.
Weft Skew: The weft yarns are skewed due to uneven feeding into the cylinder or excessive water jet impact.
Solutions: Standardize the fabric feeding method, control the boiling dyeing steam pressure, and avoid water jet impact causing misalignment.
3. Loose Board Marks: Appearing as annual rings, caused by excessive tension and temperature during winding, resulting in localized heat setting.
Solutions: Wind with cold water, and control the winding tension to avoid excessively high tension.
4. ENF Fault (Inverter Self-Tuning Abnormality): The equipment vibrates upon power-on and reports an ENF error, often due to encoder phase sequence mismatch.
Solutions: Check the encoder and motor connection status; try swapping the four wires of phases A and B to see if the vibration is eliminated.
III. Systemic Prevention Recommendations
1. Maintain Stable Temperature and Humidity: Fluctuations in workshop temperature and humidity can easily lead to fabric shrinkage and deformation. It is recommended to maintain constant environmental conditions.
2. Ensure Compliance with Pretreatment Standards: Ensure thorough desizing and scouring of the greige fabric, and maintain a neutral pH value (6.5–7.5) to avoid impurities affecting dye adsorption.
3. Regular Equipment Calibration: Check roller parallelism and tension sensor accuracy monthly, and lubricate bearings and correct stretcher curvature quarterly.
