Sub-Sea Actuators

Our range of Sub-sea Actuators is based on the hydraulic heavy duty scotch yoke design or linear heavy duty piston.

There are 3 main types;

  • IP68 which is suitable for submersion down to 10m
  • Shallow water subsea which is suitable for submersion down to 137m
  • Deep water subsea which is suitable down to 3,000m

Subsea Actuators are often supplied with manual override facilities. We can provide both handwheel (shallow applications) or ROV interface override facilities including a hybrid – ROV clamped onto a handwheel – designs.

Ascendant is also able to add accessories such as subsea limit switchboxes, subsea position feedback units (4-20mA) and subsea hydraulic quick connect fittings.


  • Double Acting (DA) or Spring return (SR)
  • Torque range – up to 400,000NM
  • Thrust range – up to 19.5KN
  • Supply – Up to 350 bar hydraulic
  • Approvals – CE, Shell, Petrobras
  • Clean room assembly of parts to NAS6
  • ROV override available
  • Feedback switches or potentiometer available
  • Special fast removal mounting spool available
  • Testing down to max. 3,000m in hyperbaric chamber
  • Painting – Epoxy paint to sub-sea standard or project specification
  • Accessories – see Component supply include limit switches and limit switch boxes

Additional Services

  • Automation system design using CAD
  • Supply of complete assembled and tested automated Valves
  • Fitting of automation assembly to free-issue Valves
  • Fitting and Testing of customer supplied components (engineering and labour only)