VariStroke is Woodward’s line of linear electro-hydraulic valve actuators for operation

of steam or hydro turbine control valves. These linear actuators utilize a low-pressure,

hydraulic oil source (typically turbine lube oil) to provide its output shaft force.

Its superb accuracy and resolution make it ideal for steam valve control and related

turbine speed and load control, where turbine up-time and availability is essential.

Features & Benefits

• Precise and stable control for responsive performance

• Variable/configurable shaft lengths for various application requirements

• Patented dirt tolerant and self-cleaning technology for increased reliability

• High-torque valve and motor design (50 lbs chip shear)

• Fast slew rates/times (up to 10”/sec)

• Side-load tolerant for reducing potential oil leaks

• Integrated driver (4-20 mA) and 11-point linearization table

• Self-tuning adaptive control algorithm

Product Variants

• Cylinder Bore Sizes:

100mm (4 in)

150mm (6 in)

200mm (8 in)

250mm (10 in)

300mm (12 in)

• Configuration

Integrated

Remote

Servo Valve Only

• Cylinder – Max. Stroke

100mm (4 in)

150mm (6 in)

200mm (8 in)

250mm (10 in)

300mm (12 in)

• Action:

Double Acting

Single Acting

No Hydraulic Cylinder

• Rod End

Male Thread

Female Thread

No Hydraulic Cylinder

• Fail-Safe Direction:

Extend

Retract

No Hydraulic Cylinder

• Compliance:

ATEX Zone 1

ATEX Zone 2