PLEM Control
Offspring International’s PLEM control systems can be operated from the surface or subsea.
Single Point Mooring (SPM) and Conventional Buoy Mooring (CBM) systems feature a PLEM containing single and multiple valves to control flow to and from the terminal. Smooth operation of the valves is critical to maximising tanker movements and trouble-free scheduling. Offspring International offers several PLEM control systems for SPM and CBM loading and offloading:
Manually controlled valve – operated by diver.
Ideal for shallow water where calm Sea States are the norm. These valves are normally left permanently open and only closed for a hose change out or in the event of an emergency. Suitable for both SPM and CBM systems.
Remote double-acting valve – operation from the SPM buoy.
The PLEM valve is controlled using a double-acting hydraulically operated actuator, powered open and closed by Hydraulic Power Unit (HPU) mounted on the CALM buoy and connected by a control umbilical.
Remote single-acting valve – operation from the SPM buoy.
The PLEM valve is controlled using a single-acting, hydraulically operated actuator, powered open by a HPU mounted on the CALM buoy and connected by umbilical. The valve is held open by hydraulic pressure and fails safe via the actuator’s spring when the hydraulic pressure to the actuator is lost.
