A unique operation of the crane boom replacement has been successfully completed on Sakhalin Energy’s Piltun-Astokhskoye-B (PA-B) offshore platform. For the first time in the world oil and gas industry practice a 48 meters long crane boom weighing 18 tonnes was installed on the operating offshore platform in adverse weather conditions.
“It was an awesome sight, – says Offshore Installation Manager Denis Lutsev.
– At first the “old” crane boom had to be transferred to the cargo ship, and then the new boom, which is the size of a 15-storied building and weighs 18 tonnes, was lifted from the cargo deck and installed on its slewing platform. Our installation team demonstrated extraordinary precision workmanship in this operation: when the boom had to be connected to special pins the accuracy of the boom positioning was measured in millimetres”.
The new boom components were manufactured by Favco, a reputed crane equipment maker. The project was implemented in three stages: the boom sections were first delivered to the island where they were assembled into a single structure at the Kholmsk Onshore Supply Base. Then the Pacific Endeavour transported the boom to the PA-B offshore platform. The final stage of the project included dismantling of the old boom and installation of the new one.
“It is common world’s practice in this case to cut off the ‘old’ crane boom using cutting torches”, says Anton Tolvanen, Senior Project Manager and Sakhalin Energy’s Lead Construction Engineer. “Our ?ompany engineers developed their own know-how, a technical procedure for detaching the bearing section of the boom from the crane making it possible to avoid hazardous hot work. On top of that, our method made it possible to preserve structural integrity of the boom“.
The unique character of the offshore operation was also due to the fact that it was accomplished in-house using the ?ompany’s own resources: onshore and offshore engineering staff which made it possible to avoid hiring external contractors and additional equipment.
The operation was planned with due regard not only for the team actions coordination, exact timing and schedules alignment, but also for weather conditions. The heavy lift had to be completed within the optimal weather window, when the ice was still holding the surge of the sea down while the season of thick fog and stormy winds was yet to come.
The focus of the project planning and execution was on every aspect of its safety, which involved a lookahead analysis of all potential risks (including compilation of the risk registers) and the development of safe practices. And no wonder that by the end of May the PA-B Platform had work 7 years without Lost Time Incidents.