Wuhu single screw air compressor which one is better

The principle of rotary screw air compression is really no different than reciprocating (piston) compression. Both are positive displacement machines that take in a fixed volume of air at atmospheric press. [pdf]

Velocity double k drilling rig

Is capable of drilling depth of 4000 m (13,100 ft) with 4-1/2" DP and represents the largest self-propelled truck mounted drilling rig in the lineup. It comes equipped with two C-18 diesel engines to serve as its main power source. [pdf]