Pre-stage helical worm gearboxes, which have an additional reduction stage with helical gears, a pre-stage helical module, located upstream of the gearbox.
The pre-stage helical module consists of 4 sizes (63-71-80 and 90), which can be coupled with a certain number of gearbox sizes.
The pre-stage gearboxes are supplied exclusively in the PAM version as the pre-stage helical module, acting as an input reduction stage, makes it unnecessary to use an input transmission.

The product designation is:

  • VRT pre-stage worm gearboxes supplied only in the PAM version