1. Equipment Preparation: Check the power supply, transmission system, temperature control system, and liquid level sensor to ensure all components are operating normally.
Clean the dyeing tank to prevent residual dye from affecting the color of the new batch.
Set process parameters according to fabric type: temperature, tension, machine speed, dye liquor pH, etc.
2. Fabric Winding: Smoothly wind the pre-treated fabric (desized, scourized, and bleached) onto the feed roller, avoiding wrinkles or overlaps.
Adjust the initial tension to ensure the fabric smoothly enters the dye bath during the first run.
3. Dyeing Cycle (Core Stage): The fabric is unwound from the passive roller, immersed in the dye bath via the guide roller, and then wound onto the active roller, completing one "one-stage" cycle.
During each cycle, the dye liquor flows continuously through a circulation pump to maintain uniform temperature and concentration.
The system achieves "three constants" through PLC and frequency converter control:
Constant linear speed: prevents fabric stretching;
Constant tension: avoids wrinkling or fabric breakage;
Constant temperature: ensures stable dye uptake.
The number of dyeing passes is set according to the fabric thickness, length, and color depth, typically ranging from 20 to 60 passes.
Key process nodes (such as adding dye, sodium sulfate, and alkali) are added automatically or manually in steps according to the program. For example, when using Annox L-type reactive dye, the typical process is:
Rolling up → Hot water wash → Adding dye → Adding sodium sulfate → Adding alkali → Heat preservation → Washing → Soaping → Unloading.
4. Post-treatment
After dyeing, the fabric needs to be thoroughly washed to remove loose dye and auxiliaries.
Dye fixing, softening, and drying processes are performed as needed to improve color fastness and hand feel.
5. Inspection and finishing
Color difference and color fastness are tested on the finished product to ensure compliance with standards.
Cut and package, ready for warehousing or the next stage of processing.
