A piston pump is a type of positive displacement pump that uses one or more reciprocating pistons to move and pressurize fluid. Piston pumps can handle high pressures, viscous fluids, and solid particles. They are widely used in hydraulic systems, irrigation, drilling, and other applications.
Piston Pump Parts
Every piston pump contains three major components: a piston, a crank, and inlet and exit valves. The piston is the main element that enables liquid to flow in and out through the valves. The crank, which is connected to the motor, rotates and allows the piston to move back and forth repeatedly. The inlet and exit valves control the direction and timing of the fluid flow.
Depending on the design and configuration of the piston pump, there may be additional parts that affect its performance and characteristics. Some of the common parts of piston pumps are:
| Part | Description |
|---|---|
| Cylinder block | It is attached to the drive shaft and rotates at the same speed as the shaft. It has axial bores that house the pistons. |
| Piston assembly | It consists of the piston, the piston rod, and the piston shoe. The piston moves in the axial bores of the cylinder block. The piston rod connects the piston to the piston shoe. The piston shoe slides on the swash plate and changes the stroke length of the piston. |
| Swash plate | It is a tilted plate that determines the angle of the piston stroke. By changing the angle of the swash plate, the displacement and flow rate of the piston pump can be adjusted. |
| Port plate | It is a plate that has inlet and outlet ports for the fluid. It is located at one end of the cylinder block and seals the fluid chamber. |
| Valve plate | It is a plate that has valves for each piston. It is located at the other end of the cylinder block and regulates the fluid flow. |
| Shaft | It is the part that transfers the rotational motion from the motor to the cylinder block. |
| Bearing | It is the part that supports the shaft and reduces friction. |
| Seal | It is the part that prevents leakage of fluid and air. |
Piston Pump Basics
The basic working principle of a piston pump is as follows:
- As the shaft rotates, the cylinder block also rotates with it. The pistons move in and out of the cylinder block due to the action of the swash plate.
- When the piston moves out of the cylinder block, it creates a low-pressure area in the fluid chamber. The inlet valve opens and allows fluid to enter the chamber. This is called the suction stroke.
- When the piston moves into the cylinder block, it creates a high-pressure area in the fluid chamber. The outlet valve opens and allows fluid to exit the chamber. This is called the discharge stroke.
- The fluid is transferred from the low-pressure side to the high-pressure side by the reciprocating motion of the pistons. The flow rate and pressure of the fluid depend on the number, size, and speed of the pistons, as well as the angle of the swash plate.
