What Are The Key Considerations When Designing A Hydraulic Power Unit?

When designing a hydraulic power unit, the design should be tailored to the specific application. A hydraulic pump unit consists of the hydraulic pump, its driving motor, coupling, and the transmission base assembly. It is not recommended to use a rigid connection between the hydraulic pump shaft and the motor shaft. Typically, an elastic coupling is used, and for larger hydraulic pump units, special electric motors with internal splines or medium flanges may be used for connecting the hydraulic pump to the motor. If the motor has significant vibration, a pulley or similar connection should be used between the hydraulic pump and motor. The radial load on the pump shaft should not exceed the manufacturer’s specified limit. If necessary, a bearing-supported bracket should be added to install the pulley or gear.

Regarding the hydraulic station’s oil tank, the design is crucial—too large is wasteful, and too small is impractical. Typically, the tank has a sloped bottom to ensure that when changing the hydraulic oil, it can be completely drained and carry away any bottom sediments. Therefore, the bottom of the oil tank should be designed with a slope; it should not have a double bottom, as this would hinder heat dissipation.

The suction pipe of the hydraulic station should not be too close to the bottom of the tank to avoid drawing in impurities from the tank floor. The return pipe should extend below the liquid level to prevent oil splashing and the generation of bubbles and noise.

If possible, it is advisable to separate the suction area from the return area. This will help increase the circulation path of the fluid, improving heat dissipation and air separation. The height of the partition should be appropriate—too low will be ineffective, and too high could cause the hydraulic pump to run dry.

The air filter should have a flow capacity greater than the hydraulic flow to compensate for any decrease in liquid level caused by the pump shaft drawing oil.

The inner walls of the oil tank should ideally be treated with spray plastic coating. Plastic offers excellent resistance to acids and alkalis, good adhesion, high impact resistance, and provides an even, smooth, and aesthetically pleasing finish, making it a preferred option for the treatment.