In a jet or soft-flow machine, every part of the rope should pass the nozzle often. This calculator gives the rope length in each tube and the time for one full circulation, and the fabric speed you need for a target cycle time.
How it works
- Fabric per tube (kg) = batch weight ÷ number of tubes.
- Rope length (m) = kg per tube × 1000 ÷ (GSM × open width in m).
- Cycle time (min) = rope length ÷ fabric speed (m/min).
- Speed needed (m/min) = rope length ÷ target cycle time.
Heavy, long ropes give long cycle times. If the cycle time is too long, reduce the load per tube or raise the reel and nozzle speed within the machine’s limits for that fabric.
Questions
What is cycle time in a dyeing machine?
Cycle time is the time one rope of fabric takes to go once around the machine: rope length ÷ fabric speed.
How do you calculate rope length?
Rope length (m) = fabric weight per tube (kg) × 1000 ÷ (GSM × fabric width in metres). Use the open width; for a tube, that is twice the flat tube width.
Why does cycle time matter?
A long cycle time means each part of the fabric sees the liquor less often, which raises the risk of uneven dyeing and crease marks. Faster circulation with the right load and speed gives more level results.