When the rotary drilling rig is working, the hydraulic oil temperature is high, which will accelerate the oxidation and deterioration of the oil, shorten the life of the oil, cause the viscosity of the hydraulic oil to be greatly reduced, cause the internal leakage of the hydraulic pump, reduce the working efficiency of the equipment, and cause the phenomenon of "powerlessness". It has a great impact on performance and life.
【Causes and possible solutions】 ①The heat dissipation is too slow ---- the hydraulic oil radiator fan does not work solution: 1. The cooling bypass safety valve is abnormally opened, and the high-temperature hydraulic oil does not pass through the oil radiator, and returns directly to the oil tank to repair or replace the safety valve. 2. The set pressure of the safety valve of the independent cooling system becomes lower, the fan speed is too low, and the cooling power is not enough. Reset the pressure. 3. The cooling gear or plunger pump is damaged, the output flow is limited, the fan speed is too low, and the cooling power is not enough, check the oil pump. 4. The output parameters of the independent cooling controller are faulty, check the circuit or re-update the controller parameters. ②Heat production is too fast-----main hydraulic system failure solution: 1. The oil level in the fuel tank is too low, and the oil viscosity is too low. Refuel or replace the oil with a suitable viscosity. 2. The internal wear of the pump is serious, the gap is too large, and the internal leakage is serious. Overhaul and replace pump. 3. Serious internal leakage of the main valve, repair or replace the main valve. 4. Serious leakage of hydraulic pump and motor, repair or replace pump and motor. 5. The main safety valve is faulty, the sealing is not strict, the high and low pressure are connected, and the overflow is serious. Repair or replace the main safety valve. 6. The bypass overflow valve of the oil filter is not opened normally, and the overflow loss is too large. Overhaul or replace the bypass overflow valve. 7. The pipeline is twisted and bent too much, and the interface shrinkage is too small. Replace the oil pipe.
According to typical oil pump requirements, the oil viscosity only operates between 13cSt and 860cSt viscosity. When the working oil temperature exceeds 72°C, the viscosity of the commonly used standard No. 46 hydraulic oil will be lower than 13cSt. Therefore, when the working oil temperature of the hydraulic oil of the machine exceeds 72 °C, it should be considered to use the hydraulic oil with a standard viscosity of No. 68 to increase the viscosity to a suitable viscosity, reduce internal leakage, and improve the working efficiency of the hydraulic oil.
