Return oil pressure

In order to working stability of the motor, request has the certain back pressure, back pressure is too large, according to the relation between torque hydraulic motor and its inlet, outlet pressure is proportional to the difference, in the inlet pressure is certain, when back pressure increase is bound to make the hydraulic motor of the import and export of reducing the pressure difference, so causing the hydraulic motor rotation weakness. Under normal circumstances the return oil pressure should be 0.3MPa~1.0MPa.

Oil drain pipe

Oil drain pipe is generally not received the system back to the oil on the road, for the motor provided with a flushing system, oil drain pipe can act as a return pipe flushing. When the motor axis in the horizontal direction when installed, should the oil drain line is connected to the discharge of oil casing in the top end of the estuary (Fig. 2). If the motor shaft is in the vertical installation, leak optional tubing should be connected to the upper end cover of the motor oil drain (Figure 2), when necessary, increase the appropriate back pressure in the oil discharge pipe on the road, the pressure is not too large, otherwise it will lead to the axial seal damage caused by leakage, back pressure value should be controlled in the the following 0.5MPa, instantaneous peak work should be less than 0.8MPa by measuring the motor case pressure know), so that the motor is always full of oil. And can reduce the running noise of motor.

Regularly and lubricating grease

Because the hydraulic motor of low rotation speed, large load, rolling bearing its internal hard to form a lubricating oil film, so should be regularly carried on the grease lubrication, cycle is generally 2000h~3000h.

Motor installation and replacement

Replace the motor as far as possible to make the motor output shaft less or not by the radial force, ensure the internal support bearing motor without extra force, otherwise, the long time use will make the oil distribution mechanism deflexion, affect its service life. Therefore, the motor in the installation of the transmission shaft is connected with other machinery to ensure concentricity, or with flexible connection. For the motor with torque arm, installation should be the first to connect the motor and the torque arm, and then fixed torque arm, in order to prevent damage to the shell or plate shaft.

Low speed high torque hydraulic motor in normal use, should first ensure enough back pressure. Back pressure should be to ensure the minimum output pressure of the hydraulic motor in no-load operation stability. Usually should be with the increase of rotational speed, improve the motor corresponding return pressure value.

Secondly, the hydraulic motor due to wear or seals aging caused by bad sealing and leakage increases, or mechanical friction force is too large, resulting in hydraulic motor flow instability, torque ripple, resulting in the phenomenon of creeping. Operation not long time working at the minimum stable speed following. Because, at low speed motor flow into fewer, larger proportion caused by leakage, lower volumetric efficiency, leading to crawling. The minimum stable speed in general multi function curve hydraulic motor can reach 0.1r/min~lr/min.

Again, for the hydraulic motor for continuous operation, avoid high temperature in continuous operation in the motor housing lead to wear gap is too large, resulting in large discharge, the shell pressure increased, the leakage to the outside of the shell, thereby causing the lower volumetric efficiency, we must carry on the cooling and flushing, flushing oil impurities can take the inside of a motor, and a sealing ring cooling effect on the radial. Rinse the loop should be independent of the system circuit.

Pay attention to capture the abnormal signals

Good at capturing the fault signal, to take timely measures. Small changes in sound, vibration and temperature will mean motor problems. Ma Daji is old, there are internal leakage, and leakage will increase with the increase of temperature. Because of the internal leakage can make the sealing gasket and the lining ring deformation so may also occur outside leakage. For motor internal leakage judgment, the author of the repair experience is: first the motor oil return pipe stop, stop flushing and disconnect the motor connected with the flushing pipe, and then the system pressure to a minimum, the oil pump is started, and gradually be pressure to normal range, can be observed and leakage of casing pressure changes in the pressure measuring point motor and oil discharge outlet, the test can be performed only when necessary two positive and negative directions.

To keep the oil clean

As far as possible to make the hydraulic oil to keep clean. Behind most of hydraulic motor faults are hidden down hydraulic oil quality. Failure is mostly solid particles (particles), any pollutants and overheating of the formation of the. Summarize experience is, hydraulic system with hydraulic motor of the oil liquid cleanliness, should be maintained at least at the level of NAS9 or less. Otherwise, containing impurities in the hydraulic oil, friction parts of the surface wear will cause Madane, wear into the groove, resulting in increased leakage.