The output flow fluctuation is related to many factors. For the Rexroth variable pump, it can be considered that the control of the variable mechanism is poor, as if the object enters the variable mechanism, step marks, wear marks, scars, etc. are drawn on the control plug, so that the control plug does not change. Due to insufficient amplifier power or damaged parts, and poor damper performance with a springless control plug, the city's control plug behavior remains unchanged. The flow is constant and often accompanied by pressure fluctuations. Such drawbacks generally need to disassemble the hydraulic pump, replace the damaged parts, increase the damping, increase the spring stiffness and control the pressure, etc.
Axial Rexroth Piston Pump Working Principle Variable Rexroth Piston Pump Maintenance and Troubleshooting, 1. The working principle is that the pump shaft and the motor shaft are misaligned or dead, the bearing and coupling of the torsion shaft are damaged, and the elastic pad is damaged Noise will occur when the removal bolts are loosened. For pumps that run at high speed or transmit large energy, check regularly and record the amplitude, frequency and noise of each component. If the vibration frequency of the pump is the same as that of the pressure valve, it will cause resonance, and the speed of the pump can be changed to eliminate the resonance.
There are no two reasons for the overheating of the hydraulic pump. One is that the mechanical friction generates heat. Because the active surface is in a dry friction or semi-dry friction state, the active parts rub against each other to generate heat. The second is heat generation by liquid friction. The high-pressure oil leaks to the low-pressure chamber through various cracks, and a large amount of hydraulic energy is lost and turned into heat energy. Therefore, the correct selection of the clearance between the active components, the volume of the fuel tank and the cooler can prevent the overheating of the pump and the overheating of the oil. In addition, the oil return filter'> filter blockage causes the oil return back pressure to be too high, which will also cause the oil temperature to be too high and the pump body to overheat.
When the inclination of the swash plate of the Rexroth variable displacement axial piston pump is zero, it is called the external position, and the output flow of the pump is regarded as zero at this time. However, there will always be a phenomenon that the external position deviates from the external point of the adjustment part, and there is still no flow output when it is at the external point. It means that the position of the controller is deviated, loose or damaged, and needs to be re-zeroed, tightened or replaced. Insufficient angular maintenance of the pump and wear of the tilt trunnion can also occur.
Rexroth piston pump output pressure is too high
Because the hydraulic system of the molding machine uses many cylinders, and the load of each station is not the same, it makes sense to use the Rexroth variable pump outside the system.
The oil inlet pipe is too thin, the flow capacity of the oil inlet oil filter is too small or blocked, the oil inlet pipe sucks air, the oil is too wide, the oil level is too low and the oil absorption is insufficient, and the liquid hammer occurs outside the high pressure pipe, etc. noise. Therefore, it is necessary to accurately design the fuel tank, and select the correct oil filter, oil pipe and target valve.
The output pressure of the pump is determined by the load, which is approximately inversely proportional to the input torque. The output pressure is very free of two types of drawbacks. 1. The output flow of the Rexroth hydraulic pump is insufficient or does not output oil
The oil leakage of the Rexroth piston pump is mainly without the following notices:
(1) The oil seal from the shaft is damaged or the shaft has no defects or scratches;
(2) If the internal leakage is too large, the pressure at the oil seal will increase, and the oil seal will be damaged or washed out;
(3) The oil drain pipe is too long to cause oil leakage at the seal;
(4) The external oil pipe of the pump is loose, the pipe joint is damaged, aged or cracked;
(5) The bolts of the variable scheduling mechanism are loose and the seal is damaged;
(6) The cast iron pump casing has no blisters or poor welding.
