Subsea Gate Valve Applications

Oliver Valvetek Limited manufactures a range of 'small bore' subsea gate valves, from 0.38'' [10mm] bore to 1.00'' [25mm] bore.

These valves typically have an opertaing pressure rating up to 15,000psi [1034bar] and a operating temperature range of -20F [29c] to +350F [+180c]. Water depth rating down to 10,000ft [3050m].

Gate Valves

Override Operator

The actuated gate valves can be supplied with an override operator, which can be used to open/close the gate valve in the event of a loss of hydraulic pressure. Different adaptors can be provided for connection to extension rods for ROV operation.

Position Indication

Clear position during both hydraulic and override operation. On the half turn gate valves, the unique offset drive pin arrangement provided for 180 degree operation.

Hydraulic Actuator Seals

Tee seal hydraulic actuator seals with Peek anti-extrusion rings are used as standard and have been tested to 7,500psi [517 bar].

Enviromental Seals

All subsea gate valves have seals to prevent the ingress of seawater. These have been tested to water depths equivalent to 10,000 feet [3050m].

Override Operating Threads

The multi-turn designs ACME thread design ensures low override operating torques.

Disc Spring Fail Close Actuator

The fail close (optional fail open) action is by way of a disc spring stack. These have been design for many operating cycles. A 50,000 cycle test was conducted on one set.

Anti-Blowout Spindle

Each size of gate valve has a spindle designed to provide an anti blow-out safety feature.

Gland Seals

The gland seal within each gate valve has been designed with a spring energised lower seal to prove dynamic adjustment of the packing gland seal in response to pressure changes. This feature ensures leak free spindle sealing with no requirement for adjustment.

Carbide coated gates and seats for long term performance with minimum wear.

Body Seal

All the gate valves have either Grayloc or Destec metal to metal body to bonnet seals.

Uninterrupted flow passage through valve

The control on the open to closed position provides clear through bore with minimum restriction to flow.