Answer: Return to the oil meter - reflecting the oil return status of the hydraulic system. The hydraulic oil return system of the drilling rig is a low pressure system, and the normal oil return pressure is between 0.3 and 0.6 MPa. When the return pressure value is greater than 0.6 MPa, the problems reflected by the oil return system include:
1The oil temperature is lower, the oil return resistance is larger, and the reflected pressure value can reach 1.2MPa. This situation generally occurs in the power-on state. At this time, it is not appropriate to let the rig work immediately, because the hydraulic components of the rig return oil system are It is a low-pressure structure, and immediate work will cause the pressure of the oil return system to increase, sometimes damaging the hydraulic components. The correct method is: the rig should be idling for a few minutes, observe the return pressure gauge to lower the normal value, and then carry out the drilling work, so as to ensure the safety of the rig;
2 When the return pressure value is continuously maintained at a value and there is a tendency to increase slowly, it should be judged that the return filter of the oil return system is clogged, causing the oil return to be blocked, and the oil return filter should be performed at this time. Cleaning, when conditions are good, it is best to take the kerosene or diesel oil to clean the spare; if there is no such condition, clean it with water in the well, and clean the attached material with a small fire stick. For the cleaned oil return filter, the attached water should be cleaned to prevent water from entering the fuel tank, causing the water in the oil tank to form a state of water-in-oil or water-in-oil, resulting in premature failure of the hydraulic oil and waste;
3When the oil return pressure gauge pointer oscillates, and the noise of the suction of the main and auxiliary pumps is accompanied, it indicates that the oil suction filter in the fuel tank is blocked, and the oil suction filter must be cleaned immediately. If the main and auxiliary pumps are short-lived for a long time. Working in the oil state will cause damage to the main and auxiliary pumps, and in severe cases, a burning accident will occur. The oil absorption filter is generally cleaned with water in the well, the flocs attached to the oil absorption filter net, various kinds of slag, etc. are cleaned, and the moisture on the filter net is cleaned. In the case of pressurized wind in the well, the pressure air can also be used to purge the suction filter. When disassembling the top cover of the fuel tank, it is necessary to prevent the pulverized coal and cuttings on the fuel tank cover and the roof of the roadway from falling into the fuel tank, causing pollution to the hydraulic oil. Pump
pressure gauge – reflects the rated pressure value of the hydraulic system; it also reflects the operating parameter pressure value when the motor rotates in the dual pump fuel supply system. According to the design, the system pressure value is 21 MPa, which reflects the limit value or capacity value of the equipment.
The hydraulic system problems reflected by the pump pressure gauge include:
1 system pressure value is too low or simply no pressure. The problem lies in the hydraulic system safety valve. The treatment methods are as follows: firstly, the system safety valve is cleaned. Since the safety valve uses a cone valve to seal the oil, when there is a foreign matter stuck to the cone valve or the cone valve is deflected, it will cause an oily situation, so that the pressure cannot be established, and the foreign matter can be removed by cleaning the safety valve. Righting cone valves, which often occur when new valves are used. Secondly, the limit spring in the safety valve is fatigued, the spring force is insufficient to cause overflow, and the pressure does not meet the design requirements. Again, the seal "O" ring in the safety valve is damaged, causing high pressure oil to leak and pressure loss.
2 When the motor rotates in the forward or reverse direction, or the one-way force is weak, the pressure value reflected on the pump pressure gauge does not meet the parameter requirements. The problem is the one-way control valve on the rotary plate valve, or the control spring fatigue, or the plate. The remaining iron filings in the valve are obstructed, resulting in a steel ball sealing oil that is not tight enough to cause leakage and pressure relief.
3 The internal leakage of the motor is damaged, the pressure cannot be established, and the pressure value reflected by the pressure gauge is always in a lower range. Fourth, the pressure gauge is damaged.
Feeding and lifting pressure gauges - reflect the rated pressure values of the incoming and outgoing systems and the values of the parameters in operation. In the dual-pump working oil circuit system, the auxiliary pump group provides oil to reflect that the system pressure value is 21 MPa. This pressure value reflects the limit value or capacity value of the feeding and pulling system; in the work, it reflects the feeding and lifting. The parameter value. The parameters reflected by the parameters of the feeding and drawing pressure gauges mainly include: firstly, reflecting the efficiency of cutting the rock by the drill in the pressurized drilling; second, reflecting the stability of the cutting rock and the mutual influence between the Drill Bit
and the rock. Third, it reflects the gas dynamics of the borehole and the sudden accidents in the borehole channel.
Sub-pump pressure gauge - reflects the pressure design value provided by the sub-pump and the parameter change value during the working process. According to the design, the secondary pump pressure value is 21 MPa, which reflects the limit value or capacity value of the equipment.
The secondary pump pressure gauge reflects the problems of feeding and lifting hydraulic systems including:
1 The feed and pull-out pressure values are too low or there is no pressure. The problem is with the safety valve on the hydraulic system. The method of treatment is the same as above.
2 The pressure value does not meet the working requirements. The problem lies in the pressure relief relief valve of the auxiliary pump plate valve block. The pressure relief relief valve should be cleaned or repaired. The valve core is stuck. If it is damaged, it needs to be replaced.
3 If there is no problem in the safety valve and the relief relief valve after inspection, check whether the plate seat has machining iron scraps to hinder the check valve operation, if necessary, clean the iron filings. After the above treatment, generally The problem can be solved.