MIR Valve Sdn Bhd ordered 12 RH rack and pinion actuators to control subsea ball valves on a jacket flooding system as part of the Petronas Carigali Sdn Bhd Bokor Phase-3 Redevelopment Project which aims to boost production rates. Jacket flooding systems are used to co-ordinate the opening and closing of flooding and venting ballast chambers using seawater to support and stabilise large offshore structures.
The Bokor field project involves the installation of three wellhead platforms while Rotork’s actuators will be installed 70 metres underwater where they will be used for on/off duty. The actuators will open the valves once within 48 hours of the jacket being submerged and provide a fail-safe return to the closed position if there is a hydraulic supply failure in future.
Rotork RH actuators were specified for the project as a hydraulic power supply is the preferred method for subsea actuation. The local service and technical support offered by Rotork Site Services (RSS) was also a key factor. Through a global team of fully trained and experienced service engineers, RSS provides on-site repairs, commissioning and maintenance to support both Rotork and non-Rotork products.
The RH range of hydraulic rack and pinion actuators offer an economical solution for quarter-turn valves which need a constant torque requirement throughout the stroke. Available in five cast iron body sizes, the actuators are capable of producing torque output up to 3,400 Nm (30,000 lbf.in) at operating pressures up to 250 bar (3,600 psi). Both double-acting and spring-return configurations are available and RH actuators comply with ISO 5211 DIN 3337 standards. The RH is also certified as suitable for use in Safety Integrity Level 3 (SIL3) applications in accordance with IEC 61508, is environmentally protected to IP67M and has explosionproof certification to ATEX 2014/34/EU standards.
The RH can operate in a temperature range from -30 to 100 °C (22 to 212 °F) as standard while high, low and extreme low variants are also available.