Shipyard installs NOV compensator

ST Engineering Halter Marine and Offshore (STEHMO) installed a National Oilwell Varco (NOV) crown mounted compensator (CMC) on Houston-based Diamond Offshore’s Ocean Blackhawk drill ship. The 215-metric-ton passive heave compensator was fully assembled and lifted on the top of the derrick in May. Carol Crane Rigging & Lifting Technology and Mammoet supported STEHMO with completing the engineered lift. Before the lift, the Pascagoula, Miss., shipyard cranes removed the existing ‘A’ frame from atop the derrick and supported (NOV) with all the modifications required for the compensator. In addition to the installation, STEHMO, formerly known as VT Halter Marine, fabricated and installed a Hydraulic Power Unit (HPU) platform and other minor alterations to the existing pipe systems. “We take great pride in offering the facilities, along with the skilled professionals necessary, to accomplish a project of this scale,” Nian Hua Lim, president/CEO of STEHMO, told Marine Link. (Source: Marine Link 07/04/19) The purpose of the NOV Crown Mounted Compensators is to apply a constant tension to the drill string and compensate for any rig movement.