Introduction


In the unlikely event of a subsea well control incident, the Offset Installation Equipment (OIE) allows installation of one of the OSRL Capping Stacks from a safe offset distance.

  • If the hydrocarbon discharge rate from the incident well creates hazardous surface conditions unsuitable for operations directly above the incident well due to surface boil and high Volatile Organic Compound (VOC) and Lower Explosive Level (LEL) levels, an exclusion zone up to 500m radius may be put in place.
  • The OIE will enable the operator to safely install the Capping Stack from vessels located outside the exclusion zone and soft shut in the well.
  • The OIE system is stored at OSRL’s storage facility in Trieste, Italy, and with it’s 234 mts weight, requires a large construction vessel for deployment.
  • The OIE is designed to operate between 75 to 600msw depth.

Logistics planning guidelines


Interactive 3D

OIE main

OIE Carrier simplified

OIE technical

Specification

How it works


  • The OIE system consists of the following subsystems:
    • a carrier with adjustable buoyancy;
    • a winch system to control the carrier position and lift payloads;
    • a cardan joint for cap fine positioning;
    • and a control system to control all functions.
  • The ballast is provided via four air ballast tanks that are supplied with air via a dedicated umbilical. This buoyancy provides sufficient flexibility to carry a variety of response equipment payloads, whilst also enabling the equipment to be configured to minimize interaction with the hydrocarbon plume.
  • Mooring winches allow positional control of the carrier in the vicinity of the well, while pennant winches allow lifting and lowering of equipment. Each of the winches has a 50mT pull capacity.
  • The cardan joint provides both the capability to align and lower the capping stack (or other equipment) onto a tilted blowout preventer (BOP).
  • The control system consists of hydraulics, power and communications supplies which are provided via a remotely operated vehicle (ROV).
  • The hydraulics utility is provided by an 01E-specific hydraulic power unit that is included in the delivery and attached to the ROV.
  • The dragchain provides passive height control (relative to the seabed) when the carrier is being moved laterally.

Carrier specification


    Carrier Ref. Mass 236 t
    Overall height: 14.023 m
    Overall width: 10.498 m
    Overall length: 13.527 m
    Region of application: Worldwide within operational WD
    Working depth min/max: 75/600 msw
    Exclusion Zone radius: Up to 1000 m
    Min/max storage temperature: -25/+50 °C
    Min/max operating temperature in air: -20/+50 °C
    Min/max operating temperature in water: -2/+50 °C
    Storage design life time: 20 years
    Continuous operating life: 6 months
    Wet storage life after CS installation: 2 years
    Net uplift: ~5-10 t
    Minimum uplift at 300 msw: 1500 kN

Equipment list

Base structure Main frame
Bracings, supports
Cardan joint, including soft landing system
ROV interface panel
ROV emergency intervention panel
Ballast tanks
Buoyancy foam
Mooring Winches
Tensioning system
Mooring lines
Drag chain
Surface equipment Control container
Workshop container
Deck stands
Air supply Compressor
Piping and deck hoses
Long and short umbilical
Winches
Overboard fairleads and chutes
Umbilical termination heads
ROV equipment ROV
0IE-specific hydraulic power unit (IHPU) skid
IHPU interface frame
Towing equipment Towing steel wire
Towing boat deck equipment
Towing lines buoyancy
Storage and transportation Transport pallets
Transport containers
Testing equipment Test cables
Dummy stab plate with connectors
Test console
Test hydraulic power unit
Assembly equipment Erection stand
Main frame assembly aid
Working platforms

Media

  • OIE Carrier Assembly

  • OIE Load Out/SIT

  • OIE Storage

  • Offset Installation Concept

  • Carrier