Drilling BOP Spherical rubber annular BOP 13 5/8"-3000PSI API Standard
APPLICATION
Annular Bop must be used with hydraulic control system.It is usually with ram type BOP,but it can also be used independently. It can be used for following operations:
1.It can seal on almost any shape of size-Kelly,drill pipe, tool joints, drill collars, casing or wireline.
2.When there is no drilling tool in hole, it can completely shut off the hole.
3.With an accumulator,forced tripping with 8°/35°welded tool joints is allowed.
WORKING PRINCIPLE
Closing action begins when hydraulic fluid is pumped into the closing chamber of the BOP below the piston. As the piston rise, it pushes the element up and the element’s spherical shape causes it to close in at the top as it moves upward. As the piston continues to rise, the element seals around the drill string or shuts off the well bore. Steel segments in the element move into the well bore to support the rubber as it contains the well pressure below. Opening action begins when hydraulic fluid is pumped into the opening chamber of the BOP above the piston. As the piston comes down, the element returns to its original position by its elasticity.