Subsea well cap trials completed off northern UK

A well-capping device has been successfully deployed in waters west of Shetland, according to industry association Oil & Gas UK.

Offshore staff

LONDON -- A well-capping device has been successfully deployed in waters west of Shetland, according to industry association Oil & Gas UK.

To strengthen the UK’s emergency response capabilities, the association’s Oil Spill Prevention and Response Advisory Group (OSPRAG) has undertaken numerous initiatives to improve well engineering and oil spill response capability.

These including developing thewell capping device for use offshore the UK to seal-off an uncontrolled subsea oil well should a major well control incident arise.

The purpose of the recent Emergency Equipment Response Deployment (EERD) exercise was to simulate the logistics involved in transporting a well capping device, loading it onto a vessel, and finally lowering it over the side before fixing it to a purpose-built, simulated well on the sea floor.

Total E&P UK managed and executed the project over a 10-day period in July at a site in block 206/4, around 75 km (46.6 mi) northwest of Shetland.

The various stages of the exercise included:
• Site prepared by deploying a specially-built landing base to the seafloor at a depth of 300 m (985 ft) to accurately simulate a subsea well
• Use of ROVs to activate subsea oil dispersant (in this case a non-toxic fluorescent dye)
• Heavy-duty cutting shears deployed to sever a subsea marine riser pipe. In a real situation, this action would be taken in order to clear the riser out of the way to make room for the cap to be landed
• Capping device deployed over the side of a multi-service vessel using a crane
• Device landed on to the well, locked on to the base, and activated using ROVs
• Recovery of all equipment, including the landing base.

Oil & Gas UK’s chief executive, Malcolm Webb, said: “The next stage will involve a full debrief involving all participants to identify any learning opportunities and Oil & Gas UK will share these findings throughout the industry.”

08/10/2011

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