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Valve Actuators

Actuation matched to the valve, not the catalogue

Pneumatic, electric, hydraulic and manual actuators for quarter-turn and multi-turn valves, supplied with the accessories that complete the assembly.

The Range

Actuators by drive type

Orbit valve fitted with an Orbit actuator

The actuator is specified from the valve’s torque demand and what the process needs to happen on loss of power or air, not the other way round.

Pneumatic, Spring Return

Fail-safe

Purpose: Compressed air drives the valve one way; a spring returns it the other. On loss of air the spring decides the position.
Applications: Emergency ShutdownOil & GasProcess Plant
Note: Choose fail-open or fail-closed to suit what the process needs on loss of air.

Pneumatic, Double Acting

High cycle

Purpose: Air drives the actuator in both directions, giving more thrust than a spring-return unit of the same size.
Applications: Modulating DutyHigh CycleLarge Bore
Note: No inherent fail position. Add a lock-up or accumulator if one is required.

Electric, Motor Operated (MOV)

Precise

Purpose: An electric motor and gear train position the valve, with limit and torque switches defining travel and cut-off.
Applications: Remote OperationWaterPower Generation
Note: Suits sites with no reliable instrument air supply.

Hydraulic

High thrust

Purpose: Hydraulic fluid delivers high thrust in a compact envelope, for large valves or high differential pressure.
Applications: PipelinesSubseaHigh Pressure
Note: Where the thrust required exceeds what pneumatic can practically deliver.

Scotch Yoke

Quarter-turn torque

Purpose: Converts linear thrust to quarter-turn rotation with a torque curve that peaks at the ends of travel, where a ball or butterfly valve needs it most.
Applications: Ball ValvesButterfly ValvesPlug Valves
Note: Torque output matches the unseating and seating demand of a quarter-turn valve.

Rack & Pinion

Compact

Purpose: A rack drives a pinion for quarter-turn rotation with a flat torque curve, in a small, light housing.
Applications: HVACWater TreatmentSmall Bore
Note: Economical where torque demand is modest and space is tight.

Manual Gear Operator

Manual

Purpose: A worm or bevel gearbox reduces the effort needed to operate a large valve by hand.
Applications: Large BoreInfrequent OperationNo Power Supply
Note: Fitted where a valve is too large to operate by lever or handwheel alone.

Actuator Accessories

Control & feedback

Purpose: Positioners, limit switch boxes, solenoid valves and manual overrides that complete an actuated valve assembly.
Applications: PositionersLimit SwitchesSolenoidsOverrides
Note: Specified with the actuator so the assembly is commissioned as one unit.

Selection Guide

Which actuator do you need?

Start from the duty and the failure mode, and the drive type follows.

ActuatorUse it whenBest suited to

Pneumatic spring

The valve must take a known position if air is lost.

Fail-safe duty

Pneumatic double

You need more thrust and will control the fail position separately.

High cycle, large bore

Electric (MOV)

There is no reliable instrument air, or you need precise positioning.

Remote operation

Hydraulic

Thrust demand is beyond what pneumatic will deliver.

High pressure, large valves

Scotch yoke

A quarter-turn valve needs peak torque at the seat.

Ball & butterfly

Rack & pinion

Torque demand is modest and space is limited.

Compact quarter-turn

Manual gearbox

No power is available and the valve is too large for a lever.

Manual operation

Already have actuators in service? We also repair and recalibrate them. See MOVs & Actuator Services.

Sizing an actuator?

Send the valve type, size, pressure class and the fail position you need. We will size it and quote.