The Well Control System or the Blowout Prevention System on a drilling rig is the system that prevents the uncontrolled, catastrophic release of high-pressure fluids (oil, gas, or salt water) from subsurface formations. These uncontrolled releases of formation fluids are referred to as Blowouts.
[pdf] The hydraulic system is the muscle of the crawler mounted drill rig, and its control is a vital part of the overall control system. Hydraulic valves are used to direct the flow of hydraulic fluid to different actuators, such as cylinders and motors.
[pdf] Reverse circulation is achieved by blowing air down the annulus of the rod, the differential pressure creating air lift of the water and cuttings up the inner tube which is inside each rod. It reaches the deflector.
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