Gas-Over-Oil Actuators


Paladon GH and GHL-Series gas-over-oil (gas/hydraulic) valve actuators use high pressure process gas to provide the energy required to power the valve actuator automating the valve. To provide increased safety and reliability, the process gas acts upon hydraulic fluid stored in gas-over-oil tanks, creating hydraulic pressure that is subsequently used to power the hydraulic valve actuator. As standard, the gas-over-oil control system provides local open and close control using either the high pressure process gas, or via a hydraulic hand pump. Numerous additional control system options are available; including linebreak detection (rate of drop and high/low) and remote control.


Automation of rotary and linear valves in gas transmission lines.

Operating Ranges

  • Supply Pressures
    • 13 to 250 Barg (90 to 3625 psig)
  • Torque & Thrust Outputs
    • GH-Series: 200 to 680,000 Nm (1,770 to 6,018,000 lb in)
    • GHL-Series: Up to 289,134 N (65,000 lbf)

Key Features & Benefits

  • Low or high pressure control system designs available
  • Suitable for operation on sour and wet power gas
  • Compact and highly reliable manifolded control systems
  • Modular control system manifolds to allow for quick, simple and inexpensive control system functionality changes or servicing
  • Fully enclosed controls with lockable cover to provide excellent environmental protection and protection from unauthorised operation
  • Hydraulic manual override as standard to allow for local open and close valve operation on loss of power gas supply
  • Local open and close valve control using power gas as standard
  • Independent open and close valve speed control as standard
  • PED or ASME approved gas-over-oil and power gas storage tanks for safe containment of power gas
  • Scotch-yoke valve actuators with symmetrical, canted and demi-canted yoke designs to ensure optimum actuator sizing and Lloyds certified for operation down to -65°C (-85°F)
  • Linear valve actuator systems available
  • Double-acting and spring-return actuator configurations
  • Valve actuators certified to IP66M
  • Valve actuators 3rd party approved for SIL 3 applications
  • Valve actuators certified in accordance with PED 93/27/EC