Halter installs passive heave compensator on Diamond Offshore drillship

(PASCAGOULA, Miss.) — ST Engineering Halter Marine and Offshore has installed a 215-mt NOV passive heave compensator on Diamond Offshore’s Ocean BlackLion. The compensator was lifted fully assembled and set on top of the derrick.

Ocean BlackLion arrived at Halter's deepwater facility in early May. Shipyard cranes were used to support the NOV with all modifications required to suit the new equipment. This contract represents the third Diamond Offshore drillship performing similar upgrades at this facility over the last year.

The shipyard team installed an MPD piping system and a ballast water treatment system, both systems were 3D laser scanned and engineered in-house aboard Diamond Offshore vessels during previous projects to avoid interference. Additional shoring of structural support were put in place to accommodate modules.

In addition, ST Engineering Halter Marine and Offshore fabricated miscellaneous platforms, performed upgrades to the ballast water treatment system and relocated the firewater system piping, in addition to painting the exterior hull. ST Engineering Halter Marine and Offshore also devised a custom solution for a mechanical tie-in for the ballast water treatment system to avoid disrupting the internal coating systems.

Ocean BlackLion is the third drillship and fifth working deepwater drilling rig to visit the shipyard under contract to work in the Gulf of Mexico over the last six months.

By Professional Mariner Staff