Trelleborg Offshore’s innovative drill riser buoyancy technology has helped offshore drilling contractor, Transocean, achieve a new record in deepwater drilling. The ultra-deepwater drillship, the Dhirubhai Deepwater KG2, achieved the record depth, 10,194 ft, during a drilling job offshore India for Reliance Industries.
Reducing weight subsea
Billy Nitsche, drilling global customer solutions manager, Trelleborg Offshore, commented: “The drill riser provides a conduit for the drill string and drilling fluids from the ocean floor to the rig. This has significant weight which must be supported by its own structure and ultimately by the drilling vessel. To reduce this weight in water to a more manageable amount, discrete drill riser buoyancy modules are fitted around the riser circumference along its length.”
Trelleborg supplied Ultra Module Integrity System (MIS) drill riser buoyancy modules (DRBMs) rated down to 11,000ft to cover 100 riser joints for the drilling rig. The unique modules are constructed from low-density composite syntactic foam which is reinforced with a proprietary sub-layer and encased in a glass reinforced epoxy (GRE) external skin.
A long and successful track record
In addition 11 joints of Trelleborg’s stackable riser guard and riser shims were specified. The innovative riser guard is a free flooding, self equalizing, neutrally buoyant unit, offering complete protection for bare riser joints and external lines during handling, storage and drilling operations.
Nitsche added: “Trelleborg has a long and successful track record as leaders in the supply of DRBMs and we are very proud to be associated with the drilling depth record achieved on this project. We are continually investing in our state-of-the-art research and manufacturing facilities to enable us to push the boundaries of technology for the offshore environment. It’s always rewarding when this pays off, but never more so than when our solutions contribute to such success.”
Transocean sets new record
By utilizing Trelleborg’s Ultra MIS drill riser buoyancy modules Transocean was able to surpass its own prior record of 10,011 ft which had been set in 2003 by the Discoverer Deep Seas working for Chevron in the U.S Gulf of Mexico, while also using Trelleborg Offshore’s drill riser buoyancy modules.
Source: , June 3, 2011; Image:transocean