Source：Jiangyin Eternal Heavy Industry Co.,Ltd. Release time：2021-08-30 14:47:17 Author：1207
What should be paid attention to when choosing a hydraulic pump?
The hydraulic pump is the power element of the hydraulic system, which determines the pressure and flow of the entire system. Therefore, hydraulic pumps should be selected according to the pressure, flow, price, working stability, accuracy, etc. The advantages and disadvantages of various pumps should also be considered.
What is the principle of choosing a hydraulic pump?
①Whether variable is required: Radial plunger pump, axial plunger pump, and single-acting vane pump are variable pumps.
②Working pressure: plunger pump pressure 31.5MPa; vane pump pressure 6.3MPa, up to 21MPa after high pressure; gear pump pressure 2.5MPa, up to 25MPa after high pressure.
③Working environment: The gear pump has the best anti-pollution ability.
④Noise index: Low-noise pumps include internal gear pumps, double-acting vane pumps and screw pumps. The instantaneous flow of double-acting vane pumps and screw pumps is uniform.
⑤Efficiency: The total efficiency of the axial plunder pump is the highest; the pump with the same structure, the pump with a large displacement has a higher total efficiency.
What are the advantages and disadvantages of various pumps?
Compact structure, small size, stable operation, uniform flow, less pulsation and noise, longer life, efficiency is generally higher than gear pumps, and the price is lower than plunger pumps. Small and medium flow vane pumps are often used in throttling control systems. Large flow vane pumps are generally only used in non-regulated hydraulic systems to avoid excessive power loss. Vane pumps are mostly used in hydraulic systems of machine tools, hydraulic presses, vehicles, engineering machinery and plastic injection machines.
The structure is simple, the price is low, the work is reliable, the maintenance is convenient, the adaptability to impact load is good, and the inertia of the rotating part is small. The bearing load is larger and wears quickly. Compared with the vane pump and the plunger pump, the efficiency is the lowest. It is mostly used in machine tools, construction machinery, mining machinery, and agricultural machinery.
It has compact structure, long life, low noise, high pressure, large flow rate, and large unit mass power ratio. It is easy to realize flow adjustment and flow direction change, but the structure is complex and the price is high. Plunger pumps, especially axial plunger pumps, are widely used in high-power hydraulic systems that require high pressure, large flow and need to be adjusted.
④ Screw pump:
It is essentially a gear pump, which is characterized by simple structure and light weight; small flow and pressure pulsation, uniform delivery, no turbulence, no agitation, and few bubbles; reliable operation, low noise, and smoother operation than gears Pumps and vane pumps, volumetric efficiency is high, and suction lift is high. However, it is difficult to process and the flow cannot be changed. It is suitable for machine tools, using two-screw or three-screw pumps, and has two installation methods, vertical and horizontal.