Liner retrieval & caisson inspection

Challenge

Stork was contracted by a major North Sea Operator in February 2015 to retrieve a partially disbonded rubber liner that was affecting caisson pump performance.

Solution

A two stage bespoke solution was designed in order to fully remove the liner from the caisson.

• Stage 1: Stork retrieved the 20 metre liner using in house hydraulic retrieval tools.
• Stage 2: The remaining parts of the liner and any debris was removed using HP water jetting. Retrieved parts were collected in a customized debris capture basket, designed and produced by Stork to ensure complete removal of any remaining materials.

Once the liner was removed, Stork was able to evaluate the condition of the caisson using remote visual inspection. Following inspection services, the team provided a scope report in a timely manner, including recommendations on how to further improve and extend caisson integrity.

Benefits

This project provided the client with a cost effective and innovative solution to improve pump performance. The two stage approach provided a bespoke solution using multiskilled personnel to deliver an effective and quick turnaround. The platform team was able to successfully reinstall the pump, reinstating the caisson to optimum performance. The visual inspection showed that the caisson was in good condition meaning no further inspection or repair was required at this stage. Stork’s specialist inspection team went the extra mile to complete the job within a tight timeframe and within budget.

Workscope: Retrieving a partially desponded liner and caisson inspection services

Date: 2015

Equipment: Hydraulic Retrieval Tools, High Pressure Water Jetting, Customized Debris Capture Basket, Caisson Inspection Tools

Safety: Project delivered with no lost time incidents and within budget