What are the different types of piston pumps?

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Plunger pumps can be divided into three main categories: axial plunger pumps, radial plunger pumps, and in-line (reciprocating) plunger pumps. In axial piston pumps, the pistons are arranged axially. When the axis of the cylinder block coincides with the axis of the drive shaft, it is called a swashplate-type axial piston gear pump; when the axis of the cylinder block and the axis of the drive shaft are not on the same line but form an angle, it is called a inclined-shaft type axial piston pump. Axial piston pumps have advantages such as a compact structure, high operating pressure, and ease of achieving variable displacement. Features of axial piston pumps: Since the arrangement of the pistons allows for an efficient use of space, resulting in a reduced radial dimension, the volume of these pumps is small. The principle of hydrostatic bearings is employed between the slip shoes and swash plate, as well as between the cylinder block and the distribution plate, which enables axial piston pumps to operate continuously at high speeds and high pressures. It is easy to achieve variable displacement, with various methods available for this purpose; moreover, multiple control methods can be integrated. The swash plate design allows for shaft-driven operation, and the inclination angle of the swash plate is usually around 20 degrees. The space required for the pump to switch from forward displacement to reverse displacement is small, which is why axial piston pumps are widely used in variable displacement pumps and those that require driven pistons. In contrast, the inclined shaft design does not allow for shaft-driven operation; furthermore, the angle between the pistons and the drive shaft is between 20° and 45°, resulting in a larger amount of space needed for the pump to switch from forward displacement to maximum reverse displacement. Therefore, it is generally used in positive displacement pumps, while this design is more commonly found in the structure of plunger motors. For more information, please visit the China Pump Industry Network.