Subsea Screening Rings

With the experience gained from many inspections in both the North Sea and the Gulf of Mexico, GUL’s Sub‑Sea GWT equipment has evolved into a reliable modular system. GUL Sub‑Sea rings are easily adjusted to fit different pipe sizes and are available for both ROV or diver deployment.

The advantages of using the Sub‑Sea rings include:

  • Screening unpiggable sections of line for internal or external corrosion/erosion.
  • Screening under weight coat and insulation with minimal cleaning and excavation.
  • The on-site analysis allows the ROV to perform follow-up indications.
Ethernet comms between instrument and the ROV or the topside box minimises time under water

    Fast Ethernet Collection

Depth rating covers the majority of subsea pipelines

    3000m max water depth

Size specific frames hold modules that can be moved from one frame to another

    Interchangeable modules

Two different frame types for deployment by a diver or an ROV

    Diver or ROV

A variety of sizes can be accommodated

    6 to 24 inch

Quick collection on station

    5 minute collection

Available Versions:

ROV Deployed

A Subsea G4mini is mounted on the ROV. A hydraulic connection is used for opening and closing the ring. The test is carried out from the ROV control room.

Diver Deployed

The test is controlled via an umbilical from a topside interface box to the Wavemaker instrument. The rings are installed on a clean section of pipe by 1 or 2 divers using a mechanical clamping mechanism.


Number of Channels 12
Nominal Pipe Sizes 6″ to 10″ (DN 150 to 250)
Operating Depth 3000m max.
Compatibility Uses Ethernet connected Subsea G4Mini


Number of Channels 12
Nominal Pipe Sizes 6″ to 26″ (DN 150 to 650)
Operating Depth Any diver depth
Compatibility Umbilical connection to Subsea G4Mini (> 50m) or
topside Wavemaker® (< 50m)