The Impeller Form Of Stainless Steel Sewage Pump

Apr 14, 2026

Stainless steel sewage pump belongs to a type of unobstructed pump, which has various forms such as submersible and dry. Currently, the commonly used submersible sewage pump is the submersible sewage pump, and the commonly used dry sewage pump is the horizontal sewage pump and the vertical sewage pump. Mainly used for transporting urban sewage, feces or liquids containing fibers. The medium containing solid particles such as paper scraps is usually transported at a temperature not exceeding 80 ℃. Due to the presence of fibers that are prone to entanglement or clumping in the conveyed medium. Therefore, the flow channel of this type of pump is prone to blockage.

Once the pump is blocked, it will not work properly and may even burn out the motor, resulting in poor drainage. It has a serious impact on urban life and environmental protection. Therefore, anti clogging and reliability are important factors for the quality of sewage pumps. Like other pumps, the impeller and pressure chamber are the two core components of a sewage pump. The quality of its performance represents the quality of the pump performance. The anti clogging performance, efficiency, cavitation performance, and anti abrasion performance of the sewage pump are mainly ensured by the two major components of the vane pump and the pressure chamber. Below are the introductions:

 

 

1. Impeller structure type:

The impeller structure is divided into four categories: blade type (open, closed), swirl type, channel type, (including single channel and double channel) spiral centrifugal type. The open semi open impeller is easy to manufacture and can be easily cleaned and repaired when blockage occurs inside the impeller. However, in long-term operation, the clearance between the blades and the side wall of the pressurized water chamber will increase due to particle abrasion, resulting in reduced efficiency. And increasing the gap will disrupt the pressure distribution on the blades. Not only does it generate a large amount of vortex loss, but it also increases the axial force of the pump. At the same time, due to the increased gap, the stability of the liquid flow in the channel is disrupted, causing the pump to vibrate. This type of impeller is not easy to transport media containing large particles and long fibers. In terms of performance, the efficiency of this type of impeller is low, about 92% of that of a regular closed impeller, and the head curve is relatively flat.

2. Swirl impeller:

Pumps using this type of impeller have some or all of the impeller retracted from the pressure chamber flow channel. So it has good non blocking performance, strong particle passing ability and long fiber passing ability. The particles flow in the pressurized water chamber and are propelled by the vortex generated by the rotation of the impeller. Suspended particles themselves do not generate energy, but only exchange energy with the liquid in the flow channel. During the flow process, suspended particles or long fibers do not come into contact with the blades, and the situation of blade wear is relatively mild. There is no increase in clearance due to abrasion, and it will not cause serious efficiency decline during long-term operation. Pumps using this type of impeller are suitable for pumping media containing large particles and long fibers. In terms of performance, the efficiency of this impeller is relatively low, only about 70% of that of a regular closed impeller, and the head curve is relatively flat.

3. Closed impeller:

This type of impeller has a higher normal efficiency. And in long-term operation, the situation is relatively stable. Pumps using this type of impeller have smaller axial forces and can be equipped with auxiliary blades on the front and rear cover plates. The auxiliary blades on the front cover plate can reduce the vortex loss at the impeller inlet and the wear of particles on the sealing ring. The secondary blades on the rear cover plate not only serve to balance axial forces, but also prevent suspended particles from entering the mechanical seal chamber and provide protection for the mechanical seal. However, this type of impeller has poor non clogging performance, is easy to wrap, and is not suitable for pumping untreated sewage media containing large particles (long fibers).

 

 

4. Flow channel impeller:

This type of impeller belongs to bladeless impellers, and the impeller flow channel is a curved flow channel from the inlet to the outlet. So it is suitable for pumping media containing large particles and long fibers. Good anti blocking performance. In terms of performance, this type of impeller has high efficiency and is not much different from ordinary closed impellers, but the head curve of the pump with this type of impeller drops sharply. The power curve is relatively stable and not prone to over power issues, but the cavitation performance of this type of impeller is not as good as that of ordinary closed impellers, especially suitable for use in pumps with pressure inlets.

5. Spiral centrifugal impeller:

The blades of this type of impeller are twisted spiral blades that extend axially from the suction port on a conical hub body. This type of impeller pump has both the functions of a positive displacement pump and a centrifugal pump. When suspended particles flow through the blades, they do not hit any part of the pump, so it has good non-destructive properties. Less destructive to the conveyed material. Due to the propulsion effect of the spiral, suspended particles have strong passability, so pumps using this type of impeller are suitable for pumping media containing large particles and long fibers, as well as high concentration media. It has obvious characteristics in situations where there are strict requirements for the destruction of the conveying medium.

In terms of performance, the pump has a steep head curve and a relatively flat power curve.

 

 

The most common type of pressure chamber used in sewage pumps is the volute, and radial guide vanes or flow channel guide vanes are often used in submersible pumps.

There are three types of snail shells:

spiral, ring, and intermediate.

Spiral volutes are basically not used in sewage pumps. Circular pressurized water chambers are commonly used in small sewage pumps due to their simple structure and easy manufacturing. However, due to the emergence of intermediate (semi spiral) pressure chambers, the application range of annular pressure chambers has gradually become smaller. Due to the fact that the intermediate type water pressure chamber has both the helical permeability and the high permeability of the annular water pressure chamber. It has received increasing attention from manufacturers.

In summary, regardless of the series of sewage pumps, it is only a combination of different types of impellers and pressure chambers according to the requirements of the conveying medium and installation, as long as the impellers and pressure chambers can achieve optimized configuration. The various performance of the pump will be guaranteed.