Pneumatic Piston Actuator PMX


Omni Model PMX pneumatic piston actuators are designed to operate surface safety or shutdown valves on oil & gas wellhead, transmission, storage, manifold or other applications where fail-safe capability is required.

Model PMX actuators can be used for land or offshore installations and are engineered to provide reliable service in a variety of operating conditions where piston, hydraulic and pneumatic actuated valves are used.

Omni provides Model PMX actuators already mounted on piston, hydraulic and pneumatic actuated valves and ready to deploy in 5,000 and 10,000 psi working pressures.


Integrated Manual Override

Model PMX pneumatic piston actuated valve assemblies are configured with an integrated manual override system to hold the valve open during well intervention or other servicing activities. The manual override cannot be separated from the actuator. This prevents loss or theft of the override mechanism while the valve is in service.

Over-Pressure Protection

Model PMX actuators come equipped with pressure relief devices to protect personnel and guard against damage to the actuator in case of an over-pressure condition. The pressure relief device is easily inspected and is field-replaceable.

Orientation, Rotation & Ease of Piping

Model PMX actuators have pressure inlet and outlet ports located at convenient locations on the upper housing assembly. The actuator can be rotated to facilitate proper piping orientation based on field conditions. Once proper orientation has been achieved, the actuator can be secured in position to prevent piping damage due to accidental rotation.

Integrated Backseat

Model PMX actuators incorporate bonnet assemblies that have an integrated metal-to-metal backseat that allows valve bore pressure to be isolated in the valve cavity while work is being performed on the actuator.

Corrosion Protection

Model PMX actuator housings are internally and externally coated to prevent corrosion due to environmental conditions. All internal components are either stainless steel or are coated to prevent corrosion due to any contamination that might be present in the pneumatic control pressure source.


Model PMX actuators are designed for ease of maintenance. All non-metallic seals and other parts are easily replaceable.

Available Sizes

Model Size Pressure (PSI)
PMX 13 2 1⁄16” 5,000
PMX 13 1 13⁄16” 10,000
PMX 13 2 1⁄16” 10,000