Subsea Valves

The Dublok range of subsea valves includes Needle, Globe, Ball and Check valve options contained within a robust manifold with a variety of end connections to suit the specific requirements of the application. Operating conditions up to 10,000 psi at 3,000 meters depth can be accommodated. Valves can be diver or ROV operated using low torque, non-rising stem activation with visible valve indication.

Special head unit configurations have been designed and proven specifically for subsea installations. Needle type (1/2” bore pipeline type / 5mm bore hydraulic service type), Globe, Ball and Check up to 2” bore are available to meet most requirements. The pipeline needle configuration has been extensively tested and proven by independent examining bodies. All these head unit types can be used in any manifold or valve body configuration to give the same versatility as the on-shore and top side range.

Robust construction, seawater ingress seals and ease of use together with the availability of various materials of construction gives superior subsea performance and extended operating life with minimum maintenance requirements.

Features

Robust design to withstand accidental damage and/or abuse which the valve may be subjected to during installation and use.
Essential elements of the head unit components are protected from ingress of sea-water by elastomeric seals. These seals are secondary to basic gland and valve seals, which are primary seals, and are so placed to protect these elements from the damaging effect of sea-water.
Most valve head types can be adapted for actuation by either diver or ROV (Remotely Operated Vehicle).
Needle valve construction uses a two-part spindle assembly with a non-rising actuation stem. This is of great advantage when being used with ROVs.
Globe and Needle valve seats are non-rotating, ensuring positive non-galling operation during shut off.
Ball valve configuration of seats (fully supported) with floating ball gives best solution for all through bore applications.

Needle Valve – Piping Class

Features
- Metal seated needle type
- 1/2” diameter bore
- Non-rotating seat
- Non-rising stem
- Optional indicator
- Non-adjustable gland packing
- Fully enclosed construction with secondary sea water seals at boundary interfaces
- Bolted bonnet construction

Applications
For pipeline applications where a through ball design is not required and with increased security of a positive metal to metal shut off to suit all service applications. Can be adapted to diver or ROV operation.

Needle Valve – Instrument Class

Features
- Metal seated needle type
- 5mm diameter bore
- Non-rotating seat stem
- Non-rising stem
- Non-adjustable gland packing
- Fully enclosed construction with secondary sea water seals at boundary interfaces.

Applications
For instrument pressure monitoring applications where flow is not required. With increased security of positive metal to metal shut off to suit all service applications. Can be adapted to diver or ROV operation.

Ball Valve – Metal Seated

Features
- Trunnion mounted
- Fire tested to BS 6755 Part 2
- Antistatic to BS6755 Part 2
- Metal to metal seats (tungsten carbide coated)
- Fitted with secondary sea water seals at boundary interfaces.

Applications
For pipeline applications where a through bore design is required. 1/4 turn shut off for ease of diver operation.

Light/Medium Duty DBB Subsea Needle Valve

Light/Medium Duty Single Isolation Subsea Needle Valves

Dublok SS 3

Heavy Duty DBB Subsea Needle Valve

Globe Valve

Features
- Outside screw and yolk
- Non-rotating stem tip
- Metal to metal seat
- Body seals – pressure energised
- Metal to metal wing seal with sea water seal back-up
- Bolted bonnet construction.

Applications
For pipeline applications where a through ball design is not required. With increased security of positive metal to metal shut off. Can be adapted for diver or ROV operation.

Check Valve

Features
- In line, spring loaded piston
- Metal to metal seat (soft seat available as option)
- Inconel spring
- Tandem construction for extra security
- Sea water seals at boundary interfaces.

Applications
For injection service where the process fluid is being conditioned. Prevents process backflow of conditioning fluid if pressure falls.