Mission pump is a broad concept of a common pump. Different regions, habits ultimately will not be involved in the pump as the same. Mission pump means to the borehole during drilling to transport mud or water and other fluid mechanically. Mission pump is an important part of the equipment. In common circulation drilling, it is the surface flushing medium─ slurry water or polymer fluid─ at a certain pressure after passing a high pressure hose taps, drill column and the drill hole and then directs the bottom of the drill, for the purpose of cooling the drill bit, and the cutting down of debris being removed and transported to the surface. Mission pump has common types of piston or plunger. Power machine is driven by the crankshaft rotary pump and crankshaft is driven by crosshead then reciprocates the piston or plunger pump cylinder. In alternating suction and discharge, valves play role in achieving the purpose of pressure delivery and circulating fluid.
The two main performance parameters of mission pump: displacement and stress.
Displacement is the discharge certain in liters per minute. It is related with the hole diameter and the back speed of the required fluid from the bottom of the hole. Pore size is so that the greater displacement is required. And rate of return on the fluid is required to be able to cut down the drill cuttings ﹑ rock powder promptly and wash them from bottom of the hole, and reliably bring them to the surface. When the geological core drills, the return rate is generally 0.4 to 1.0 m / min or so.
Pump pressure depends on the depth of the borehole, the resistance of the fluid passage through and the nature of the transmission fluid. The deeper drilling, the greater the pipeline resistance, the higher the pressure needed. With the depth changes of whole diameter, the displacement of the pump can be adjusted at any time. The flow meters and pressure gauges shall be equipped in the mud so that make the changes clearly. And it always making people understands the pump drilling operation \ transfer case, while the holes by pressure changes determine whether the condition of the hole is normal to prevent the occurrence of accidents.
Compared with shear pump , which is to quickly configure and handle mud solid control equipment to meet the configuration requirements of high-performance mud, mission pump can deliver a high concentration of high-viscosity <10000PaS and slurry containing particles suspended and transports flow stably without over-current, pulse and mixing, cutting slurry phenomenon. What’s more, discharge pressure has nothing to do with the speed and low flow can maintain a high discharge pressure. That’s why mission pump plays an important role in the project, however shear pump is also important because of the different roles. Working with mission pump and shear pump can be the best way for the project process.