Ultra Power roller screws

Ultra power roller screws HR
The SKF Ultra Power range of planetary roller screws is designed for heavy loads and long service life.

This range has been optimized to provide a capacity increase up of to 60% over the standard SR roller screw with the same combination of diameter and lead and to reach the maximum possible service life within a compact space.
For a given screw nominal diameter, the basic load carrying capacity does not fluctuate much with the lead. This unique characteristic helps the roller screw selection with regard to the required speed and life, while maintaining the same load carrying capacity, resulting in increased design flexibility for customers.

SKF planetary roller screw kinematics operate with continuous rolling motion of the rollers without recirculation. Thus, they are highly reliable for high load applications with short strokes, rapid and/or frequent changes of direction.

Features and benefits

  • Length up to up to 8 000 mm (please consult SKF for longer screws)
  • Standard lead precision G5 (ep=25µm/300mm)
  • Lead precision G3 (ep=12µm/300mm) and G1 (ep=6µm/300mm) on demand
  • Axial play up to 0,1 mm
  • High rotational speed depending on screw nominal diameter: N.d0 max = 160000 (for example,  2133 RPM for screws with nominal diameter 75) Rotational speed up to 2 650 rpm (for screws with nominal diameter 60 mm)
  • Standard wipers
  • Optional support bearings. Please consult SKF
  • Many strong contact points for heavy load capacity and long service life
  • Rollers synchronized by toothed rings, resulting in exceptional performance in applications with frequent changes of direction
  • Rollers guided for even circumferential load distribution
  • No torque variation during changes of direction
  • Axial play or preloaded execution on request
  • Long lead up to 50 mm for high linear speed
  • High axial stiffness
  • Easy nut disassembly from the shaft if necessary
  • Ability to operate in contaminated environment with minimum loss of performance
  • Adaptable tooling for non-standard, left hand thread or special designs
  • No miniature parts to improve robustness and reliability
  • Availability of customized designs

Technical data of the HR range

Nominal diameter
from 60 to 240 mm
from 15 to 50 mm
Basic dynamic load capacity
up to 3994 kN
Basic static load capacity
up to 23387 kN
up to 12 000 rad/s2

Typical applications

  • Presses for plastic injection moulding and blow moulding
  • Electromechanical presses for cold forming
  • Broaching machines
  • Large machine tool
  • Off-highway vehicles
  • Oil and gas
  • Steel industry
  • Hydro-electric power plants
  • Powerful electromechanical cylinders
  • Lifting and handling
  • And many other applications
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