... case, main drive system, transmission, double hoist group, mud pump, turntable, derrick, steel wire rope feed mechanism are installed ... and ps mechanical seal sand pump, positive cycle IS150-125-315 water centrifugal pump, 2 bv5121 motor vacuum pump suction vacuum, ... a horizontal reciprocating two-cylinder double-acting piston mud pump, through the pneumatic control clutch combination and separation; ...