Used in drilling operations with non-uniform wellbore diameters or frequent tripping of drill string

Also used in certain completion and workover operations where ram BOPs may not be practical

Important safety device in oil and gas drilling operations, legally required to be installed and regularly tested

Equipped with hydraulic control system to pack off annular spaces with different sizes

Capable of fully packing off the wellhead if no drilling tool is present

Can pack off annular spaces between well barrel and Kelly, cable, and steel wire during coring or well-test operations

Equipped with pressure-relieving/adjustable valve and accumulator to perform running/retrieving bit with force using 18 degree butt-weld drilling rod without fine thread