Diagnosis of the walking weakness and vibration lo

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Diagnosis of weak walking and vibration loss of vibratory roller

when troubleshooting, we follow the principle of easy first and then difficult to do the following inspections: first, check the faults outside the hydraulic system, including whether the engine power is sufficient and whether the speed is sufficient; Whether the manual control mechanism is loose, stuck or the stroke is not in place; Whether the voltage and current are normal. Second, check the oil quantity and quality of the hydraulic oil tank and whether the oil filter is dirty. After eliminating the above factors, diagnose according to different faults

1 ﹐ diagnosis of weak walking fault

(1) check whether the connecting parts between engine and hydraulic pump, hydraulic motor and driving wheel have mechanical faults; Check whether the bypass valve installed on the front drive motor is in the channel state after the user purchases the equipment, which can be used to realize multiple functions. If so, the high and low pressure oil chambers will be connected

(2) check the braking system. When the engine works normally and the solenoid valve is powered on, check whether the brake can be disengaged. If it cannot be disengaged, check whether there is a mechanical fault. If not, drag the brake to release the brake (rotate the handle of the manual pump counterclockwise), and then do the following checks

(3) check the high pressure and oil replenishment pressure of the main circuit of the walking hydraulic system. Connect 60MPa oil pressure gauge to the two high-pressure pressure taps respectively, and connect 4MPa oil pressure gauge to the oil replenishment pressure tap and test the machine. At normal temperature (30~60 ℃), the oil makeup pressure is about 2.6MPa, and it is not less than 2.4Mpa when the machine is moving; When running against resistance, the maximum pressure of the main circuit can reach 38Mpa, which is not less than 20MPa during normal walking. If both are normal, the fault is mechanical

if the oil replenishment pressure is lower than the specified value, place the walking control lever in the middle position to adjust the overflow valve of the oil replenishment pump (Note: observe the oil replenishment pressure gauge during adjustment, the adjustment range should not be too large, and remember the original position). If the pressure cannot reach the normal value or the reading of the pressure gauge does not exist, therefore, the R & D centers of covestro, large and small, can quickly provide them with technical consulting services such as polyurethane and polycarbonate, It can be judged that the overflow valve or make-up oil pump is faulty; If the oil make-up pressure is normal when the machine is not running, so the oil make-up pressure will drop a lot during the running operation, then measure the back pressure of the oil return pipe on the running motor, which can not be met elsewhere, and the pressure should not be less than 2MPa. If the pressure is low, it indicates that the shuttle valve and low-pressure overflow valve of the motor are faulty; When the oil make-up pressure is higher than the specified value, the pressure of the overflow valve can be reduced. If it cannot be reduced, the overflow valve is faulty

if the high pressure is low, the fault may be caused by hydraulic pump, hydraulic motor and multi-function valve block (including high-pressure overflow valve). The two main pipes of the pump can be removed, and the outlet of the pump can be blocked with plugs. The engine runs at idle speed, and the walking rod is pushed forward and backward slowly at a small angle. If the pressure is abnormal, the multi-function valve block should be removed and inspected. If the multi-function valve is normal, it is caused by the internal leakage of the hydraulic pump; If the high pressure is normal, the motor is faulty. How to judge which motor is faulty or both motors are faulty? The oil inlet and return pipes of the front and rear motors can be removed respectively, and the motor whose pressure is still abnormal after the test run is blocked is the faulty motor; It can also be judged by measuring the oil drain volume of the motor. The method is to disassemble the oil drain pipe of the motor and connect the measuring cylinder. Under normal pressure, the oil drain volume of 3~4l/min is normal, otherwise it indicates that the motor is faulty

2 ﹐ diagnosis of vibration system fault

(1) after eliminating the electrical fault, check the elastic coupling between the vibration motor and the vibration shaft and the condition of the lubricating oil in the vibration shaft. Too much lubricating oil will make the vibration frequency unable to go up, which is generally caused by the oil leakage into the shaft due to the damage of the motor combined oil seal. If the spline sleeve of the vibration shaft is seriously worn, it will also lead to vibration loss, such as the recycling of biodegradable plastics, high-tech functional new materials and waste plastics as environmental friendly plastic products. At this time, the oil replenishment pressure and system working pressure should be tested, so as to make a diagnosis

(2) since the front and rear vibration systems of the machine are independent and interconnected (share the make-up oil pump), the component replacement method can be used for diagnosis. For example, when the vibration frequency of one wheel is low, the pipelines of the front and rear 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 displacement control valve used for frequency conversion operation can also be diagnosed by the same interchange method

(3) the initial starting pressure of the vibration main oil circuit can reach 32Mpa, and its continuous working pressure can reach 20MPa when the vibration amplitude is large, and about 12MPa when the amplitude is small. When the continuous working pressure of the engine at the rated speed is much higher than the standard value, the rotation flexibility of the vibrating shaft should be checked, that is, rotate the vibrating shaft with a special tool to make the eccentric block in the high position and then release it. At this time, the vibrating shaft should be able to swing several times. If you feel great resistance, you should replace the bearing of the vibrating shaft

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