Non-Rotating Protectors Allow Drilling Ahead with High Riser Deflection
Riser Deflection Limits Drilling Window
A semi‐submersible rig drilling in 8,125ft (2,477m) of water experienced 110 hours with the lower flex joint (LFJ) differential angle greater than 0.5° and had to stop drilling ahead. Ocean currents caused riser deflection and elevated concern for stress in the riser and LFJ wear. NRPs Reduce Concern of Wear Installing SS‐658‐SC model non‐rotating protectors (NRPs) through the deflected lower flex joint or ball joint reduced concern for wear. The NRP sleeve maintains standoff of the drill pipe tool joint. In 110 hours with the differential angle greater than 0.5°, drilling ahead for 43 hours was possible using NRPs. The table below was provided by the operator.