Offshore rigs need to be surveyed every year, with the intensity of examination increasing between annual, intermediate, and 5-year frequencies. Examination includes numerous challenging compartments and spaces, including seawater tanks (normally closed and sealed), rig legs (hundreds of feet tall), the underside of helidecks (over water). An operator introduced the use of drones for tank surveys, thus mitigating risk and introducing commercial efficiency as a significant amount of preparatory costs were avoided and the rig outage time was reduced considerably.
The operator decided to pioneer the region’s first drone inspection of tanks and hull structures for offshore units among the drilling contractors, thus demonstrating how the this technology can be applied to improve safety, eliminate risk, increase efficiency, and reduce costs. In a pilot trial of the concept, the company demonstrated how a typical week-long inspection program can be completed in a single day—a cost and efficiency improvement of almost 700%. Risks include lack of oxygen, fall from heights, and injuries from obstructions. Of course, experienced industry staff members take great precautions before attempting such tasks. In fact, companies have developed golden rules that govern activities inside confined spaces.
Scaffolding needed to be erected inside tanks using specialized crews at considerable cost. Tanks needed to be ventilated in advance of entry in to the tanks. Work needed to be conducted at height with staff working on scaffolding with limited lighting. Rig time was being lost when it was brought to the jetty for surveys to ensure safe access before surveys could be conducted.
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