FPT – Fluid Power Technology has designed and manufactured the special hydraulic bolt tensioners
used on the Hebron offshore platform
The Hebron oil field is located offshore Newfoundland and Labrador, Canada in the Jeanne d’Arc Basin 350 kilometers southeast of St. John’s.
The field was first discovered in 1980, and is estimated to produce more than 700 million barrels of recoverable resources.
The water depth at the Hebron field is 93 metres (Mean Sea Level).
Hebron Platform Illustration. The Hebron field is being developed using a stand-alone concrete gravity based structure (GBS). The GBS consists of a reinforced concrete structure designed to withstand sea ice, icebergs and meteorological and oceanographic conditions.
The FPT hydraulic bolt tensioners were used for controlled tightening of the bolted joining connecting the offshore platform to the supporting tower below the sea level.
Twelve threaded studs with 15 mm pitch M138 have been tightened to minimize seizures due to the highly corrosive environment between nuts and studs and to facilitate future maintenance operations if required. The used bolt tensioner has a working pressure of 1000 bar, stroke 15 mm, force 7350 kN to 1000 bar and spring return execution to facilitate the operations.