I. Pre-Operation Preparation
1. Personnel and Protection: Operators must receive professional training and wear acid- and alkali-resistant gloves, protective goggles, and work clothes to prevent skin contact with dye liquor or inhalation of harmful gases.
2. Equipment Inspection: Inspect all components of the dyeing machine (circulation pump, nozzles, guide rollers, valves) for damage and ensure there are no residues or foreign objects clogging them.
3. Material Preparation: Accurately weigh the dye and auxiliaries according to process requirements, and select the appropriate nozzle diameter based on the fabric type (e.g., lightweight or heavyweight) (e.g., 50mm for lightweight fabrics, 100mm or more for heavyweight fabrics).
II. Parameter Setting and Start-up
1. Water Level and Liquor Ratio Setting: Set a reasonable liquor ratio (the ratio of dye liquor mass to fabric mass) based on the fabric weight. Typically, the liquor ratio for overflow dyeing machines is 8:1, while for spray dyeing machines it can be as low as 4:1 to 6:1 to save water.
2. Temperature and Time Control: Set the heating rate, holding time, and final temperature of the dyeing program (e.g., high-temperature dyeing with disperse dyes can reach 130℃). The heating process must match the dye liquor flow rate to prevent uneven dyeing.
3. Liquid Flow Regulation: Adjust the return valve: Open valve I fully, and appropriately close valves II and III, especially valve III, to prevent lag or blockage of thin fabrics.
Nozzle Gap: Adjust symmetrically left and right to ensure consistent fabric speed and avoid dyeing deviation.
III. Monitoring During Operation:
1. Start-up: Start the main pump to circulate the dye liquor. After the fabric runs smoothly for 3-5 minutes, close the dyeing tank door, then add dye and auxiliaries to prevent mechanical blockage.
2. Dynamic Monitoring: Observe the fabric running smoothly in real time, checking for tangling or knotting.
Monitor the dye liquor temperature. If it exceeds 85℃, immediately stop the machine and close the return valve. Note the alarm system: When the fabric circulation time exceeds 180 seconds, the equipment will automatically alarm and stop to prevent dyeing spots.
IV. Dyeing Completion and Post-Processing
1. Shutdown Operation: After dyeing is complete, stop the equipment, turn off the power, and wait for the temperature inside the tank to drop to a safe range before opening the tank and removing the fabric to avoid burns.
2. Cleaning and Maintenance: Drain the dye liquor promptly and clean the dye tank, nozzles, and filters to prevent residues from affecting future use. Perform anti-corrosion maintenance when the equipment is not in use for an extended period.
3. Safety Lockout: Before opening the door, ensure the pressure has been released to prevent burns from hot liquid splashes. Pay particular attention to residual pressure and the risk of hydrogen peroxide decomposition.
