How should the heating rate of the dyeing machine be controlled?

1. The importance of heating rate control
The heating rate directly affects the dyeing rate, the expansion degree of the fiber and the final dyeing effect. Improper control may lead to problems such as uneven dyeing, color flowers or color differences.
2. Control of heating rate in different temperature sections
Normal temperature to 80℃: The dye uptake rate in this temperature section is low, and a faster heating rate can be used, usually around 2℃/min.
80℃ to 110℃: This temperature section is the key stage for rapid dyeing of the dye, and the heating rate should be strictly controlled below 1℃/min.
110℃ to 130℃: The dye is basically dyed, and the heating rate can be appropriately increased to 1.5℃/min.
3. Recommendations for heating rate of specific dyes
Disperse dyes: Below 90℃, the heating rate can be slightly faster; above 90℃, especially when close to 130℃, the heating rate should be controlled to slowly approach the dyeing temperature.
Nylon dye: 65-85℃ is the key temperature range, the heating rate should be strictly controlled, and the leveling agent should be added, and the step-by-step heating method should be adopted.
4. Other considerations for heating rate control
Dye liquor circulation state: Ensure that the dye liquor circulates fully and the dye liquor temperature is uniform, which is conducive to the uniform dyeing of the fabric.
Temperature compensation: Since the temperature sensor may only measure the temperature of a certain point in the dye tank, it is necessary to set the temperature compensation value to ensure that the actual temperature of the dye liquor is consistent with the set value.
Process parameter optimization: According to the levelness of the dye, the depth of dyeing and the circulation state of the dye liquor, the heating rate should be reasonably set.