Troubleshooting of vibration roller walking weakness

In the investigation of vibratory weak fault, we follow the "easy first" principle to do the following: one is the fault check outside check hydraulic system, including the adequacy of engine power, speed not enough; manual operating mechanism is loose, death or stroke is not in place; whether the voltage and current normal. Two is to check the hydraulic tank fuel quantity, oil quality, oil filter is dirty, etc.. After the above factors are excluded, the diagnosis is made according to different faults.

Fault diagnosis of 1. walking weakness

(1) check the engine and hydraulic pump, hydraulic motor and driving wheel connecting parts are installed in the mechanical fault; check whether the motor drive bypass valve in the channel state, if high, low pressure oil chamber will be communicated.

(2) check brake system. In normal operation, the engine solenoid valve is energized, the brake is disengaged, such as can not be disengaged, should check whether the mechanical failure, if not, can adopt the method of the brake drag, lift the brake (counterclockwise rotation manual pump handle), then do the following check.

(3) check the high pressure and oil filling pressure of the main circuit of the walking hydraulic system. 60 MPa pressure gauges are connected at two high pressure measuring ports, and the 4MPa oil pressure gauge and test machine are used at the oil filling pressure measuring port. At normal temperature (30~60 DEG C), oil supply pressure is about 2? 6 MPa, when walking machine is not less than 2? 4MPa; when the maximum pressure resistance across the main circuit can reach 38 MPa, normal walking is not less than 20 mpa. If both are normal, the fault is mechanical.

If the oil supply pressure is lower than the set value, the walking lever is placed in position to adjust the pump relief valve (Note: the adjustment of observation fill oil pressure gauge, the adjustment is not too large, and remember the original position), if the pressure can not reach the normal value or pressure change, can determine the relief valve or repair oil pump failure; if the machine not go up the oil pressure is normal, so the operation of oil supply pressure is walking down a lot, should be measured walking motor return pipe back pressure, the pressure should not be less than 2 MPa, if the pressure is low that spindle motor and valve low pressure relief valve failure; when the oil supply pressure is higher than the the specified value, can reduce the pressure relief valve, if not lowered, for overflow valve malfunction.

If the high pressure is low, the fault may be caused by hydraulic pump, hydraulic motor, multi-function valve block (including high pressure relief valve). Two charge pump can be removed with the plug blocking the outlet of the pump, the engine idling, slow forward, small angle push rod walk, if the pressure is not normal should be dismantling the multifunctional valve block, if the multifunctional valve is normal, caused by leakage in the hydraulic pump; such as high pressure and normal pressure, for motor fault. How to determine which motor fault or two motors are respectively before and after the fault? Remove motor inlet and return pipe, with the plug after the test machine, the motor pressure is still not normal for the motor fault can be measured by the motor; the amount of oil leak judging method is open and connected to a motor vent pipe that is normal in normal pressure discharge oil 3~4 l/min, otherwise the motor fault.

2. fault diagnosis of vibration system

(1) after checking out the electrical faults, check the vibration of the elastic couplings and the lubricating oil in the vibration shaft of the vibration motor and the vibration shaft. Too much lubricating oil will cause vibration frequency not to go, usually due to motor combination seal damage to the shaft caused by oil leakage. If the vibration shaft spline sleeve wear seriously, it will also lead to vibration failure. At this point, the oil pressure and the system working pressure should be detected, so as to make diagnosis.

(2) since the front and rear vibration systems of the machine are independent and interconnected (common pump), the "component replacement method" can be used for diagnosis. For example, when there is a low vibration frequency, the pipeline of the front and rear two motors can be interchanged. If the fault has been transferred, it indicates that the fault is on the pump, otherwise the motor is faulty. Similarly, the same "interchangeability method" can be used to diagnose the displacement control valves used for variable frequency operation.