Roll motors

The roll motor developed by Randax is ideal for use as a direct drive motor on the spreader rolls of paper machines. This roll motor innovation is a prime example of an integrated special motor and the related benefits. The patent is pending for the motor solution in several countries.

The energy-efficient and compact roll motor makes use of the spreader roll’s bearings. It is installed between the roll sleeve and the supporting articulated bearing, i.e. in place of the belt drive used in traditional solutions. The rotor of the direct drive Randax motor is directly supported by the rotating sleeve of the spreader roll and its bearings. The stator and the motor frame are attached to the static shaft of the roll.

The fully developed Randax® direct drive motor solution provides the user with numerous benefits:

Precise motor speed adjustment ensures good spreading efficiency and high-end product quality

  • Optimal spreading improves the operability of the paper machine!
  • The direct drive synchronous motor means that the roll rotates at exactly the same speed as the motor – no belt drive problems!

A maintenance-free motor reduces operating costs

  • The direct drive solution eliminates the need for belt drive servicing and adjustment!
  • ‌The motor has no bearings – so there is no need for greasing!

 The direct drive roll is delivered as a complete unit

  • ‌The motor comes pre-installed when the roll arrives at the factory or is installed in the paper machine!
  • It is supported by the roll, which means that no separate adjustment platforms or foundations are required!

Benefits of using a special motor

  • The compact permanent magnet motor fits inside cramped spaces
  • High efficiency – energy savings
  • Corrosion-resistant materials for demanding environments
  • Can be designed for different roll sizes and power requirements

Technical specifications and nominal values:

Motor type:  Permanent magnet motor


HS Model 

LS Model


400/690 V 400/690 V


118 Hz  24 Hz


1770 RPM  180 RPM


30 kW    1 kW


46 A    6,9 A


55  55 


152 kg 118,5 kg