The GV20 is a Marine Drill rig for nearshore and offshore geotechnical operations. It is equipped with a heave compensation system and a 3-in-1 Bottom Hole Assembly(BHA) suitable for offshoregeotechnical drilling. The unit height of the GV20 marine drilling rig is 20 meters and is rated to a maximum load of 30 tons. The drill string is advanced via a Top Drive DANDO 500 Rotary Head which is motion compensated and fitted with a Mud Swivel and 4-inch stainless steel ball valve with air actuator.
The drill string comprise of collars and the standard 5-inch API drill pipes will be lowered through the seabed frame(SBF). Drilling with sea water or polymer mud depending on the the subsoil encountered will be carried out via a Duplex Double-Acting Mud Pump.
The power swivel is connected to the drill string by means of a drive sub which is flanged to the hollow spindle and has a 4.5-inch IF pin on its lower end to suit the drillstring. Control of the drilling would be from the drill console which would be equipped with a 4 spool valve bank and fitted with gauges for the compensator charge / blow down, mud flow and power swivel.