Platform Well Conductor Removal Solutions
(Champion: EnQuest) – April 2020
Platform Well Conductor removal vertically via the pin and cut method (either by platform equipment or by heavy lift) is an established method. However, technical challenges exist with the integrity of casings and grout bonding, changes (repairs, support shims etc), access and connector design and supports. Non-rig-based solutions were also of interest.
Operators were looking for examples of proven successes, and for new innovative (technical and commercial) solutions and efficiency gains to this specific cost challenge. Solutions should be carried out in a safe and environmentally diligent manner, while considering the requirements of access and platform support systems and facilities.
Determine the best methods and innovations proposed by the supply chain with respect to the five specific sub-tasks highlighted below:
The subsea separation cut of the conductor strings (internal or external cutting) above the seabed. The conductor will contain various casings, potentially separated by grout and with marine growth externally. Assuring that the cut was successful is key.
Subsea pinning, through the conductor strings.
Lifting of the conductor string, whether in tension or compression, depending on conductor integrity.
Topside ‘pin, cut then lift’ repetitive process, which involves the boring and insertion of a pin, cutting the conductor string and then lifting the sections. The desire is to achieve both step change and incremental improvements, to some or all parts of this process, whether by platform-based rig or rigless lifting systems.
Solutions for the removal of conductor anodes, shims, guides, clamps/repairs etc. when these are required to be removed to support effective removal.