How do I adjust the caterpillar belts to give the correct nip pressure?

These instructions only refer to a Servo-Torq® combination rotary cutter with integral caterpillar infeeder/puller machine fitted with the following options:

  • Air operated upper caterpillar belt.
  • Adjustable turret-stop assembly.
  • Upper belt position counter.

Belt nip pressure refers to the amount of force applied to the extruded tube or pipe to prevent it slipping between the belts.


The two most important considerations when setting the caterpillar belt position & nip pressure:

  1. The two belts (upper & lower) must be set at the correct height. This is to ensure that the tube/pipe can enter the inlet cutter guide bush without snagging or fouling on the edge of the bush.

The tube or pipe must always line-up with the bore through the cutter bushes.

  1. The amount of belt pressure on the tube/pipe must be sufficient to prevent the product from slipping or moving between the belts.

If the belts aren’t gripping the tube or pipe sufficiently well, the extrusion won’t be pulled smoothly. It will slip between the belts. This will have a very negative impact on cut length accuracy.


Never put your hand or fingers between the extruded material and the turret assembly.

The belts may close unexpectedly, trapping your hand or fingers!



For more technical advice please email our Tech Team on:

Downloads (PDF):

> Setting nip pressure datasheet.