Hydraulic pumps are divided into gear pumps, piston pumps, vane pumps and screw pumps. Each pump has its own characteristics and is applied in different mechanical or industrial equipment.
I. Gear Pump
Pressure range: 2.5~28MPa; displacement range: 0.3~650ml*r; flow fluctuation: large; higher speed: high; volumetric efficiency: 0.7%~0.9%; total efficiency: 0.6%~0.8%; self-priming performance: excellent; noise: large; price: lowest; pollution resistance: excellent; commonly used in construction machinery.
II. Vane Pump
Pressure range: 6.3~21MPa; displacement range: 0.5~480ml*r; flow ripple: small; higher speed: low; volumetric efficiency: 0.8%~0.95%; self-priming: excellent; general; noise: small; price: low; pollution resistance: medium; commonly used in situations requiring low noise.
III. Piston pumps
Pressure range: 4.0~70MPa; displacement range: 0.2~560ml*r; flow fluctuation: large; higher speed: medium; volumetric efficiency: 0.85%~0.9%; self-priming: poor; noise: maximum; price: expensive; pollution resistance: poor; good anti-pollution performance for low noise applications.
IV. Screw Pump
Pressure range: 2.5~10MPa; displacement range: 25~1500ml*r; flow fluctuation: minimum; higher speed: maximum; volumetric efficiency: 0.8%~0.9%; self-priming performance: best; noise: minimum; price: expensive; pollution resistance: poor; flow and power maximum, mostly for high power applications.