1. Uneven Dyeing (Color Variation, Batch Difference, Tube Difference)
Symptoms: Color differences, streaks, patches, or inconsistencies in color between different batches/tubes.
Main Causes:
Poor dye liquor circulation; insufficient main pump flow or head, leading to uneven dye penetration.
Significant differences in fabric length or distribution in each tube, causing different fabric circulation cycles and resulting in tube difference.
Inconsistent process parameters (temperature, time, liquor ratio), or performance differences between different dyeing batches, leading to batch difference.
Fiber fuzz clogging nozzles or pressure taps, affecting dye liquor atomization and distribution.
2. Equipment Leakage and Sealing Failure
Symptoms: Leakage at dyeing batches, pipe joints, or drum doors, posing a safety hazard.
Main Causes:
Aging, damage, or improper installation of sealing rings.
Corrosion and cracking at welded joints, especially prone to occur after long-term operation in high temperature and humidity environments.
3. Temperature and Pressure Abnormalities
Symptoms: Inaccurate temperature control, slow heating, large pressure fluctuations, even triggering alarms and shutdowns.
Main Causes: Scale buildup or aging of heating elements, sluggish response of cooling valves.
Faulty or blocked pressure sensors, unable to provide real-time system status feedback.
Failed safety valve calibration, affecting high-pressure operation safety.
4. Abnormal Temperature and Pressure
Symptoms: Inaccurate temperature control, slow heating, large pressure fluctuations, even triggering alarms and shutdowns.
Main Causes: Scale buildup or aging of heating elements, sluggish response of cooling valves.
Faulty or blocked pressure sensors, unable to provide real-time system status feedback.
Failed safety valve calibration, affecting high-pressure operation safety.
5. Mechanical System Failure
Symptoms: Abnormal noise, vibration, transmission jamming, chain skipping, etc.
Main Causes: Insufficient lubrication of bearings and gears, or deteriorated lubricating oil.
Transmission chain too loose or too tight, causing skipping or accelerated wear.
Damaged main pump bearings or worn impeller, affecting circulation efficiency.
6. Control System and Electrical Failure
Symptoms: PLC alarms, touchscreen lag, program inability to start, data loss.
Main Causes: Oxidation of electrical components, loose wiring terminals, causing poor contact. The motor insulation resistance has decreased, posing a short circuit risk.
The control system firmware has not been updated, resulting in poor compatibility or bugs.
6. Other Common Problems
Pilling or creases: Caused by improper airflow control or excessive fabric width during airflow dyeing, resulting in compression as the fabric passes through the nozzles.
Dye liquor crystallization or reagent precipitation: Caused by incomplete cleaning of the dyeing vat or improper dye liquor preparation leading to blockage.
Frequent machine shutdown alarms: Often caused by false sensor alarms, incorrect parameter settings, or improper operation.
