The axial pump components are not much different from the centrifugal pump. The most noticeable difference is the diffuser design between the centrifugal pump and the axial pump. In accordance with the impeller design, centrifugal pumps are emphasized to generate high head fluid pressure, while axial pumps emphasize high flow fluids. For that, the diffuser design on the centrifugal pump (in this case is the volute casing) is more “extreme” when compared to the diffuser in the axial pump.
Based on the image above, here are the main parts of the axial pump:
- Pump Inlet. This part becomes the inlet side of the fluid to get into the pump. In a vertical axial pump, the inlet side is funnel-shaped (so-called Suction Bell) in order to reduce the hydraulic head loss.
- Impeller. Impeller becomes the main part of this pump. The design is similar to a propeller on a ship. This impeller serves to induce an axial force which is transferred to the working fluid.
- Diffuser. The axial pump casing is also like a diffuser-shaped on centrifugal pump. Its function is to lowering the pump speed and raise the working pressure. However, the design is not as extreme as the volute casing of the centrifugal pump, because the increased outlet pressure of the axial pump outlet may cause vibration and reduce the working life of the axial pump. Once again, the main function of axial pump is to achieve high fluid flow, not high fluid pressure.
- Shaft. Serves to continue the rotation of the electric motor to the impeller.
- Guide Bearing. Serves to hold the position of the shaft to stay on the axis line work. These bearings require a lubrication system that must be maintained to avoid temperature rise.
- Stuffing Box. Is a sealing system that serves as a barrier between the shaft with the casing to avoid leakage.
Here is the detailed picture of axial pump parts: