DUDLEY, UK -- RotaBolt tension control fasteners have been chosen for new Expro-manufactured open water lubricator valves (OWLV). The valves are being used on offshore drilling rigs as a safety testing device in open water riser systems.
The OWLV is used as part of an open water riser system during the installation and work over of subsea trees. It typically sits 50-200 m (164-656 ft) below the rig floor and allows the introduction and external pressure testing of the downhole tooling string.
"This is the first time we have used RotaBolt technology," says Chris Cusack, Expro design engineer. "We have been very pleased with it and found that the installation and tooling times were considerably reduced."
The RotaBolt 2 system was selected because it provides a range of tension control on installation, tightening, and in-service checking. It offers two tension settings in a single sensor and features a dual load indicator cap – the outer cap for high tension setting and inner cap for low tension – giving the choice of an operational tension range for overload or maintenance control
The OWLV also allows testing of the riser string and surface well control equipment above it, and provides an additional safety barrier between the subsea wellhead and the drilling rig. Each OWLV is approximately 132 in. (3,353 mm) long, has an external diameter of 24.20 in. (950 mm), and a through bore of up to 7.375 in. (187 mm). Ten RotaBolt 2 fasteners are fitted to the flanges at each end of the OWLV.