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Hydraulic Rotary Actuators – SM4

The Eckart SM4 rotary actuator is a heavy-duty and highly-customizable rotary actuator designed for the toughest and most-demanding applications.

Because of its torque, angle of rotation, pressure range, positioning accuracy, stability of position, type of attachment, and its dimensions, the Eckart SM4 rotary actuator can be used in a wide range of applications. Not only is the SM4 a compact and robust unit, but it is also wear-resistant and efficient. The SM4 can be configured with an industry-leading fine and controllable end cushioning curve. Additionally, the SM4 unit can be driven via “black and white” or with proportional, control, and servo valves. For the purpose of subsequent driving, the piston end-positions at the linear cylinder and at the rotary actuator can be scanned via electronic end-position acknowledgement mechanisms. Ultimately, with the SM4, you have a high-performing product that is both robust and compact, allowing for optimal adaptation depending on your specific requirements.

Helical Spline Hydraulic Rotary Actuators:

Our rotary actuators are the helical spline design. This means, a piston and a helix, or sliding spline, work together to convert the linear motion of the piston into rotational motion. Composed of two moving parts and some form of housing, the sliding helical splined gear concept within the actuator is used in many applications where a rotary movement is required. Helical Spline Actuators function when the piston is axially displaced using hydraulic pressure causing simultaneous rotation of the piston. Standard amounts of rotation are 90°, 180°, and 360°; but are available generally up to 720° or more. Additional rotation is created by making the spline gears longer while maintaining the same diameter. The primary benefit to this type of product compared to alternative designs such as linkages using hydraulic cylinders (linear actuators) is its compact design.

Hydraulic Rotary Actuator Standard Features:

  • Torque output to 750,000 in-lb (85,000 Nm)
  • Pressure rating at 3,625 psi (250 bar)
  • Standard rotation: 90°/180°/270°/360°
  • Externally adjustable end stop ± 5°
  • Wear resistant moving parts
  • Four-point contact bearing to withstand extreme radial and axial loads
  • Adjustable home position
  • Tight backlash of 20 angular minutes

Hydraulic Rotary Actuator Optional Features:

  • End cushioning including sophisticated damping curves
  • Tighter backlash as low as 5 angular minutes
  • Position indication through encoders or proximity switches
  • Drive shaft configurations, such as spline shaft, tooth hub, hollow shaft, key shaft, etc.

Hydraulic Rotary Actuator Custom Configurations Available:

  • Drive shaft
  • Drive shaft on both ends
  • Adjustable end position rotation
  • Rotation more than 360°
  • Reversed turning direction
  • Direction connection of valving
  • Operating pressure over 2,625 psi (250 bar)
  • Operating speed
  • Mounting flanges
  • Special housing and gear materials
  • Special paint
  • Sea and saltwater resistance

Eckart is a supplier and rotary actuator manufacturer for various applications including construction, mechanical, marine, and industrial.

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