Woodside awarded Greater Western Flank subsea installation scope to Fugro TSM. Cube were involved in the design of the subsea equipment (refer 029) and were engaged by Fugro-TSM to provided permanent equipment design, installation aid design and construction engineering support.
The scope included:
- Pipeline hold-back clamps for restraining the pipeline against walking forces
- A pipeline alignment and clamp installation frame.
- A chain handling gantry beam
- Umbilical clamps
CUBE was able to collaborate efficiently with the Fugro-TSM project engineers to develop fully functioning and code compliant designs. The use of 3D models to present and agree design concepts greatly helped to reduce the design requirements, cost and schedule. Early delivery of approved design documentation allowed Fugro-TSM to start fabrication early and protect their supply schedule. The scope was completed within Cube’s cost estimate.
The bolt tension and clamping pressure the subsea umbilicals had to be managed carefully so as not to exceed the external pressure limits of the umbilicals, whilst generating sufficient friction to function. Belleville washers (also known as a coned-disc spring washers) were used to manage and control the bolting tensions.
Each of the 16″ pipeline clamp half shells weighed 500 kg. Cube designed the overhead gantry type frame to assist with installation.
A chain handling gantry beam cantilevering from the pile tops was also designed.