Working principle of hydraulic pump: use the constant change of sealing volume to realize oil absorption and pressure.
Oil suction condition of the pump: the oil tank is connected to the atmospheric pressure.
The working pressure of the pump refers to the pressure of the pump output oil, which is only related to the load resistance. When the load is large, the working pressure is large, and when the load is small, the working pressure is small. Load includes pipeline resistance, external load, friction of relative moving parts, etc.
The nominal (rated) pressure of the pump refers to the maximum allowable working pressure of the pump during operation, which is limited by the structural strength and leakage of the parts of the pump itself.
The displacement of the pump refers to the volume of oil discharged by one revolution of the pump shaft. The common unit is cm3/r.
The theoretical flow of the pump refers to the volume of oil output by the pump per minute (regardless of leakage). The common unit is l/min (L / min), which is equal to the displacement of the pump multiplied by the speed.
Gear pump the gear pump is installed in the pump body and pump cover (front and rear covers) through a pair of meshing active and passive gears, which are separated into two closed spaces (oil suction chamber and oil pressure chamber). When the driving wheel is driven to rotate, the volume of the oil suction chamber gradually increases to form a local vacuum. The atmospheric pressure will put the oil pressure into the pump, and the volume of the oil pressure chamber will gradually decrease to release the oil pressure.
The damage of the pump is mainly manifested in the following aspects: the decrease of efficiency makes the hydraulic components unable to work.
The damaged parts are mainly: the shaft sleeve of the gear shaft is worn; The inner surface of the shell is worn; The side plate is worn.
The wear of the shaft sleeve of the gear shaft will lead to the wear of the inner surface of the housing; Contamination of hydraulic oil is the main cause of early wear of gear pump.
It is of little value to repair the worn gear pump, because when it is worn, all parts are damaged almost at the same time. For gear pumps with more than two connections, there may be damage to the spline sleeve which plays a connecting role in the middle during use (at this time, it shows that some gear pumps do not work). At this time, it can be solved by replacing the spline sleeve.
