The impeller of the water pump is made of cast iron. The blade on the pump impeller plays a main role, and the shape and size of the pump impeller are closely related to the performance of the pump. Pump impellers can generally be divided into single suction type and double suction type two, single suction impeller for unilateral suction, small flow pump impellers for this type. The double suction impeller absorbs water on both sides, and the large flow pump impeller adopts the double suction impeller. It can be manufactured by CNC engraving, Sand Casting, transparent acrylic(PMMA/PC) 3D Printing.

Centrifugal pump impeller mainly has the following four forms, closed, front half open, back half open, open these four.
1. Closed impeller: composed of blade and front and rear cover plate. The efficiency of the closed impeller is higher and the manufacturing difficulty is greater. It is most commonly used in centrifugal pumps. Suitable for transporting clean water, solution and other small viscosity without particles of clean liquid.
2, semi-open impeller: there are generally two structures: one is the front semi-open, composed of the back cover and blade, the impeller of this structure is less efficient, in order to improve efficiency need to be equipped with adjustable clearance sealing ring, the other is the back semi-open, composed of the front cover and blade, because the same sealing ring can be applied to the closed pump impeller. The efficiency is basically the same as that of the closed impeller, and in addition to transporting liquid, the blade also has the sealing effect of the back blade or the auxiliary impeller. Semi-open impeller is suitable for conveying liquid containing suspended solids such as solid particles and fibers. Semi-open impeller is less difficult to manufacture, low cost, and strong adaptability. In recent years, the application of centrifugal pumps in refining and chemical industry has gradually increased, and it is used to transport clean water and liquids similar to clean water.
3, open impeller: only blade and blade reinforcement, no front and rear cover of the impeller. The number of open impeller blades is less 2-5 pieces. The impeller of the pump has low efficiency and less application, which is mainly used for conveying liquids with high viscosity and slurry liquids.
The blade of the centrifugal pump impeller is generally a backward-bent blade. The blade has two kinds of cylindrical shape and twisted shape, the application of twisted blade can reduce the load of the blade, and can improve the suction performance of the centrifugal pump, improve the anti-cavitation ability, but the manufacture is difficult and the cost is high. Pump impeller Centrifugal pump for refining and chemical industry requires the impeller to be cast or all-welded integral pump impeller. The welded pump impeller is developed in recent years, which is mostly used for casting metal materials with poor performance, such as iron and its alloys, and is a special centrifugal pump for chemical industry. The geometric accuracy and surface finish of the welded pump impeller are better than that of the cast impeller, which is conducive to improving the efficiency of the centrifugal pump.