Drilling derricks and Rig Masts consist of a steel framework with a square or rectangular cross-section. Their purpose is to support the hoisting equipment and rack the tubulars while tripping pipe. The numbe.
[pdf] Air-lift reverse circulation drilling technology is often used in geothermal well drilling, but there are many problems along with drilling depth increasing, such as double-wall drill pipe leaking, air-water mixer blo.
[pdf] ARCH drilling combines direct air rotary drillingwith the simultaneous operation of a casing hammer. An oversized casing is driven into an undersized bore using air as a circulation medium, allowing for efficient.
[pdf] 
