High Torque starting of Viscose Dryer solved by an industrial drive
Viscose is used as raw material for textiles and hygiene products. The raw material for viscose itself is pulp. Before going to the dryer, the pulp is converted into viscose in a complex process. The viscose dryer process can be divided into two parts; the spike conveyor and the dryer. The spike conveyor feeds the wet viscose to the dryer as a fluid feed. In the dryer, fans suck the wet viscose tightly into rolls. At the same time air dries the viscose.
The old PWM drive could not produce enough high torque from the start if the silo was full. So the silo filling time was limited only to 2 and half minute by the drive. By replacing the old drive with a new DTC-controlled industrial drive, sufficently high torque could be produced and the full capacity of the silo could be utilised.
The viscose dryer
Solved Problem
- The silo is working as an in-process stock for wet viscose
- Heavy duty starting is required, when the stock is full
- The old AC drive could only produce half of the required torque
Solution
- Motor: 5.5 kW, 1500 rpm
- Industrial drive 11 kVA, 7,5 kW
Benefits
- DTC enabled sufficiently high torque at the start
- Increased process reliability