NOV's two main predecessors, Oilwell Supply and National Supply, were founded in 1862 and 1893, respectively. These two companies manufactured and distributed pumps and derricks. In 1930, acquired Oilwell Supply. In 1958, merged with National Supply. In 1987, National Supply merged with USS Oilwell to become "National Oilwell". Varco was founded as Abegg and Reinhold Company by Walter Abegg and Baldwin Reinhold i.
[pdf] SWMC-SWDS 115AN integrates the advanced technology of the current split pneumatic drilling rig. The prototype has passed over 3000 hours of destructive operation experiments and 4 kinds of field tests in different geological environments. It has improved more than 10 mechanical loopholes.
[pdf] As a kind of friction clutch that uses compressed air as manipulating power source, pneumatic-tyred clutch is widely used in such equipment as oil drilling rig and workover rig, and is also an important part of the drive systems of oil drilling rig and workover rig.
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