Our client designed a decommissioning Conductor Recovery System for installation on a Norwegian offshore platform

A lifting solution was required to manoeuvre saws, drilling, and pinning tooling into position on system prior to pipe recovery and avoid any reliance on platform cranes.

Power and control solutions were required to cover supply and operate entire system. Considerations had to be given for footprint on platform and the high flows and pressures required by system resulting in a kW requirement that could surpass platform supply. The system offers a SWL lifting capacity of up to 300 metric tonnes supplied via hydraulic cylinders and the client wanted a solution to safely monitor the SWL while in operation. Any equipment provided had to be suitable to operate in hazardous areas offshore and be NORSOK compliant with redundancy capabilities.


Solution

Brimmond provided two fully foldable rental marine cranes converted to be used within a Zone 2 Hazardous Environment and certified to Norksok Z015. Hydraulic overload device on cranes safely stops all functions when boom structures are overloaded and load cells were mounted on hooks for monitoring SWL. A manual emergency pump recovery system was supplied to allow the operator to move and lower the load from the crane during a failure of power supply.

Two Zone 1 45kW Electric Hydraulic Power Units were used to collectively run the system with a third provided as a backup to avoid any downtime during operations. A separate containerised auxiliary tank was supplied to cover high flows and pressures required. Individual framed units allowed for flexibility when installing on deck.

ATEX Zone 1 Data Logging Jacking Load Unit to allow client to monitor entire system lifting capacity via load pins on the system hydraulic cylinders. The unit included ATEX load display panel, overload warning lights (90%, 100% SWL) and emergency safety cut offs.

Jacking Tower Control Panel housed within a DNV 2‐7.3 certified lifting frame that can operate various functions including the lifting/lowering jacking circuit, cranes & saw supply, drilling units and two air operated spiders. Supplementary control functions were also included for any future modifications.


Scope of supply

2 x Norksok Z015 certified EFFER Zone 2 440M Marine Cranes 2 x Atex Zone 1 Load Cells

2 x Hydraulic Emergency recovery system

3 x Norsok Z015 certified Zone 1 45kW EHPU 1 x Auxiliary Tank 1 x ATEX Zone 1 Jacking control system 1 x ATEX Zone 1 Data logging jacking load system