The closing time of annular BOP preventers The main disadvantage of the annular preventer in a drilling rig is the time required to close it. The annular preventer takes three to ten times the fluid volum.
[pdf] DTH technique was used in well drilling exclusively to dig, accurate, vertical bores, and rotary drilling was used to turn the hole. The Directional DTH system, patented by Atlas Copco, was first used.
[pdf] Each screw machine must be equipped with a gas storage tank and, if needed, auxiliary equipment such as a cold dryer and a filter. The installation requirements are as follows: A) The installation sequence of supporting equipment is: “air compressor → gas tank → gas-water separator → cold dryer.”
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