maintenance of mud pump in geological drilling 2018-09-14 16:29:52

maintenance of mud pump in geological drilling

As an important equipment in the mud circulation system in geological exploration work, the mud pump plays a key role in conveying the water, mud and other flushing materials for the drilling to ensure the smooth progress of drilling production. Therefore, it is extremely important to have an in-depth understanding of the role of the mud pump, the performance parameters of the mud pump, and routine maintenance and maintenance.
Mud is the “blood” in drilling work, and mud pumps are extremely important equipment in mud circulation systems. How to carry out regular maintenance and scientific and reasonable maintenance of the mud pump in drilling construction is of great significance to improve the service life of the mud pump and thereby maximize the economic benefits of drilling production.

1 The role of the mud pump

Mud pumps are an important part of drilling machinery. Its main function is to drill the mud into the well with the drill bit during the drilling process, play the role of cooling the drill bit, cleaning the drill, fixing the well wall, driving the drilling, and bringing the cuttings back to the ground after drilling. In the commonly used positive circulation drilling, the mud pump sends the surface flushing medium—clear water, mud or polymer flushing liquid to the bottom end of the drill bit through a high-pressure hose, a faucet and a drill pipe center hole under a certain pressure. The purpose of cooling the drill bit, removing the cutting debris and transporting it to the surface is achieved.

2 mud pump performance parameters

Theoretical displacement and working pressure are the two most important parameters of mud pump performance. The theoretical displacement of a mud pump is usually the volume of the medium that the pump discharges per unit of time. It is related to the speed of the return from the bottom rinse and the diameter of the bore. The larger the diameter of the hole, the larger the displacement it needs. The speed of returning from the low-flush liquid from the hole should be able to flush the cut rock powder and cuttings out of the bottom of the hole in time and reliably return to the surface. The working pressure of the mud pump can generally be regarded as the liquid force per unit area at the discharge port of the pump, which can be referred to as pump pressure. The amount of pressure of the pump can be determined by the resistance of the rinsing fluid conveyed through the channel and the depth of the hole. If deep drilling is required, the channel resistance is greater and the required pressure is correspondingly higher.

As the depth and diameter of the borehole change, the displacement of the mud pump can be adjusted accordingly. In order to achieve the purpose of changing the displacement of the mud pump at any time, a hydraulic motor or a gearbox is usually provided in the structure of the mud pump. The mud pump is usually equipped with a pressure gauge and a flow meter, so that the displacement of the mud pump and the change of the working pressure can be accurately grasped, so that the drilling personnel can understand the operation of the mud pump at any time, and at the same time judge the drill through the change of the pressure. Whether the condition in the hole is normal can prevent accidents in the hole.

In addition, rated power and efficiency are also important performance parameters of mud pumps. The input power of a mud pump is usually the energy that the power machine transmits to the drive shaft of the mud pump per unit time. The working power of the mud pump and the rated impulse (the number of times the pump is called the pump stroke, which refers to the number of reciprocations of the piston per unit time) is called the rated power of the mud pump. Effective power, also known as water power, is the added energy of a liquid after it has been pumped through a mud pump per unit of time. The ratio of the effective power to the input power of the mud pump is called the efficiency of the mud pump.

Mud pumps can be divided into single-acting and double-acting types. The single action is that the piston reciprocates once, the mud pump can make one suction and discharge. The double action is that the piston divides the liquid cylinder into two working chambers. The two working chambers have a suction valve and a discharge valve. The piston reciprocates once and can be performed twice. Inhalation and discharge process. According to the number of cylinders of the mud pump, there are three types: single cylinder, double cylinder and three cylinder. With the rapid development of drilling technology, the mud pump is gradually required to have a large working pressure, power and displacement. Conventional three-cylinder single-acting mud pumps are easy to maintain and reliable in all types of drilling industry and are still commonly used.

3 Mud pump maintenance and maintenance

Usually the mud pump can be divided into two parts - the power end and the hydraulic end, and the working process can be divided into two processes of inhalation and discharge. The power end of the mud pump is composed of a connecting rod, an eccentric wheel, a crosshead, a crank, etc., for transmitting power, converting the moving speed and the movement mode, thereby providing suitable power for the hydraulic end. The hydraulic end is composed of a piston, a pump cylinder, a suction pipe, a suction valve, a discharge pipe, a discharge valve, etc., and can convert mechanical energy into internal energy of the liquid, thereby being used for slurry transportation. During the alternation of inhalation and discharge, the purpose of circulating and pumping the flushing liquid can be achieved. The medium transported by the mud pump usually has high viscosity, large sand content, high pressure and certain corrosiveness. This requires reasonable daily maintenance and maintenance of the mud pump and prolongs the service life of the pump.

The installation of the mud pump must be stable. Before the mud pump is turned on, carefully check the lubrication, fastening status and clearance between the various components in the pump. Try to avoid the frequent pumping of the mud pump. When opening or reversing the pump, it is necessary to prevent the vaporization of the medium in the pump and prevent the temperature of the medium in the pump from changing greatly during the conveying process. The reason is that the temperature change will cause the pump body to be unevenly heated. It may cause deformation, aging, etc. of components inside the pump. In addition, turn the motor or pulley by hand to check the internal obstacles during rotation and adjust the belt tightness as appropriate. In addition, it is necessary to check whether there is any dirt blocking the inlet pipe and the outlet pipe, and add grease to the bearing to check whether the bottom valve is closed tightly and open and closed freely. Check the seal of each part to prevent water leakage, air leakage, etc.

The particle size of the mud pump during the construction process is related to the service life of the vulnerable parts of the mud pump. The suction line of the mud pump is not allowed to leak. The particle size of the pump should meet the requirements to avoid the blockage of mud pump by large particles. The bearings, pump casings and impellers of the mud pump are the most vulnerable parts. The bending of the bearing of the mud pump or the deviation from the bearing housing will increase the wear of the pump components and cause vibration of the pump body. The damage of the mud pump blades is mostly caused by cavitation of the pump or by inhalation of solid or metal impurities. Always check and replace consumable parts, or try to use more advanced anti-wear technology measures to increase the service life of consumable parts.

Do the maintenance of the mud pump. First, we must ensure that the oil quantity and oil quality of the lubricating oil are clean. We need to release part of the oil bottom and replenish some new oil every month, and ensure that the oil can be changed once every six months. The second is to always check the temperature changes of various parts of the bearing, whether there is abnormal noise, if the temperature is too high, it will burn the bearing. The third is to constantly check the working condition of the piston and cylinder liner and replace the piston in time. The fourth is to check the use of the bonnet and the cylinder head seal, so that it can be replaced in time. The fifth is to check whether the working conditions of the mud vibrating screen, desilter, sand remover and sand pump are normal. The sixth is to check the piston and safety pin of the safety valve to ensure that the mud pump can operate safely under drilling conditions. Seventh, it is necessary to conduct a comprehensive disintegration inspection every two years, to detect the clearance of the bearing for maintenance and repair, and to regularly pump the mud pump in order to prolong the service life of the mud pump.

4 Conclusion

The construction unit shall have special personnel responsible for maintaining and maintaining the mud pump, regularly inspect and maintain the mud pump, be able to find problems in time, solve problems, and try to avoid the shutdown of the installation or even the entire project. In the process of mud pump construction, in order to achieve the maximum efficiency of the mud pump, each mechanical component device can work normally and continuously, and the project can be completed as scheduled, and it is necessary to ensure that the various components of the mud pump can operate normally. Therefore, regular maintenance and maintenance of the mud pump is essential.