I. Pre-operation Preparation
1. Equipment Inspection: Verify that temperature gauges, pressure gauges, and safety valves are responsive and functional; check that the motor and electrical circuits are free of leakage; ensure the filter screen is clean and unobstructed; and confirm that the vessel seals are intact with no risk of leakage.
2. Dye and Chemical Preparation: Verify dye and auxiliary quantities against the recipe; prepare a slurry of disperse dyes using cold water for 20–30 minutes, then dilute with warm water (40–45°C); filter all materials through a screen before use.
3. Safety Protection: Operators must wear protective clothing and rubber gloves; clear flammable or explosive materials from the surrounding area; and ensure fire-extinguishing equipment is in place.
II. Startup and Fabric Loading
1. Turn on the main water, power, and air supplies; release the emergency stop button to start the equipment; and set the operation mode to "Manual."
2. Open the vessel door; sew the fabric to be dyed into a continuous loop (rope form) and stack it neatly in an "S" pattern within the storage trough; close the door and lock it securely.
3. Fill with fresh water according to the set liquor ratio and start the circulation pump to initiate dye liquor flow.
III. Dyeing Operation
1. At 40°C, add acetic acid and run briefly to adjust the dye liquor pH to 5–6; then add the filtered dye and continue running for 10 minutes.
2. Raise the temperature according to the process curve: control the heating rate at 2°C/min until 80°C, then reduce to 0.5–1°C/min between 80°C and 130°C; hold at 130°C for 30–45 minutes; monitor fabric movement through the viewing port throughout the process to prevent fabric jams or tangling.
3. Adjust nozzle pressure during operation based on fabric thickness to ensure the temperature change does not exceed 1.5°C per fabric circulation cycle.
IV. Post-dyeing Processing
1. After dyeing, slowly cool the bath to 85°C and vent all residual steam from the vessel; do not open the vessel door until the pressure gauge reads zero and the temperature drops below 80°C. 2. After removing the fabric, proceed sequentially with reduction clearing, rinsing, and neutralization; upon completion, verify the shade to ensure it meets requirements.
V. Equipment Cleanup and Shutdown
1. Clean the dyeing vat according to standard procedures: for light-colored products, a hot water rinse suffices; when switching from dark to light shades, boil the vat with caustic soda and a scouring agent at 130°C for 60–90 minutes, and scrub the filter screen.
2. Sequentially turn off the water, electricity, and air supplies; complete the equipment operation logs and clean the work area.
