Critical Off-Shore Oil Rig

Safety is paramount on offshore platforms. If there is any doubt on integrity of safety equipment, drastic protocols are in place but at the expense of production. UTComp made an emergency visit to an offshore platform in the North Atlantic to investigate a downed PROD boom. The results were expedited so the company could make the right decision quickly.

OVERVIEW

After a significant weather event, inspection identified potential damage to a PROD boom. PROD booms are essential for keeping rescue boats safe during evacuation of the platform. Due to safety concerns and regulations, platform was required to down-man and drastically limit production. Production loss of 230,000 barrels daily during the time boom was out of service. Immediate solution was required. This study recounts the expedient assessment conducted by UTComp on lifeboat boom condition.

SUMMARY

PROD boom is used to position 2 lifeboats away from the oil rig when they are released in emergency evacuation. Booms are typically made from Fiber Reinforced Polymer (FRP) and engineered to provide the required structural properties. In November, a boom on an offshore platform rotated from the operating position to the maintenance (inverted vertical) position. After this rotation occurred, an unknown length of the boom was exposed to extreme ocean swells. The effect of the strong wave action across the boom was unknown and visual inspection identified an area of damage. An emergency site visit by our Chief Technical Officer was required. On arrival, the boom’s condition was still in the maintenance position with some weathering. The inspection was completed while the boom was in this position. An inspector with rope access training was given instruction in the UltraAnalytix^® data collection methods.

The external inspection procedure generally follows the principles of API 653 and was adapted to this specific FRP experience. A longitudinal damage in the middle joint was detected during the external inspection. Ultrasonic readings were taken along the crack using UltraAnalytix^® inspection techniques. Another small feature was visible and inspected thoroughly. The interior surface of the boom was inspected using a borescope for any signs that damage occurred. No indications were detected on the inner surface.

A crack in the middle joint

A small gouge in the gel coat

CONCLUSION

After careful review of the data, calculations and the inspection report, UTComp determined the condition of the boom. The results showed the longitudinal damage in the middle joint was small scoring in the gel-coat that was limited to the thickness of the gel-coat. Therefore, it was classified as cosmetic damage with no structural effect on the FRP of the boom. A small gouge was deemed insignificant due to the fact the glass fibers were still contained in resin and no disruption of the FRP structure was detected. All photos from the internal inspection show that the interior had no resin damage. Because of the emergency of this situation, UTComp was able to expedite the analysis and results. The boom was confirmed suitable for continued service quickly and the oil platform was able to return to full operating capacity within 24hrs after the results.

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OWNER: Global Oil and Gas Company | FACILITY LOCATION: Gravity Based Platform, North Atlantic
INSPECTION DATE: November 2018 | INSPECTOR: Geoff Clarkson, Chief Technical Officer
ENGINEERING ANALYSTS: Mark Putt, Stephen Cha,
Arthuran Chundramoorthy, Trent MacKay, Colin Perry