Sewage sewage pump encyclopedia knowledge

Sewage sewage pump encyclopedia knowledge

Sewage sewage pump is a non-clogging pump, with many forms: such as submersible and dry type, the current submersible type is WQ submersible sewage pump, common dry sewage sewage pump such as W type horizontal sewage Sewage pump and WL vertical sewage sewage pump two kinds. It is mainly used for the transportation of urban sewage. The feces or liquid contains fibers. The medium of solid particles such as paper dust, usually the medium temperature is not more than 80°C. Due to the medium being transported, it contains tangled or bunched fiber material. Therefore, this kind of pump flow path is easy to be blocked, and once the pump is blocked, the pump will not work properly, and even the motor will be burned, resulting in poor drainage. It has a serious impact on urban life and environmental protection. Therefore, anti-blocking properties 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 the sewage pump. The pros and cons of its performance, it also represents the merits of the pump performance, sewage pump sewage pump anti-blocking performance, the level of efficiency, and cavitation performance, anti-abrasion performance is mainly guaranteed by the leaf pump and the pressure chamber two major components. Here's a description:
1. Structure of impeller: The structure of the impeller is divided into four categories: vane type (open type, closed type), cyclone type, flow channel type, (including single flow channel and double flow channel) spiral centrifugal type, open type The semi-open impeller is easy to manufacture. When the impeller causes blockage, it can be easily cleaned and repaired. However, in the long-term operation, under the abrasion of the particles, the clearance between the blade and the side wall of the pressurized water chamber will be increased, thereby increasing the efficiency. reduce. And the addition of gaps destroys the pressure differential across 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 clearance, the stability of the liquid flow state in the flow channel is destroyed, causing the pump to vibrate. This kind of impeller is not easy to transport. Medium of large particles and long fibers, from the performance point of view, this type of impeller has low efficiency, high efficiency is equivalent to about 92% of ordinary closed impeller, and the head curve is relatively flat.
2. Swirl impeller: Pumps using this type of impeller, because the impeller partially or completely retracts from the pressure chamber flow path. Therefore, the non-clogging performance is good, and the ability to pass the granules and the long fibers are strong. The particles move in the pressurized water chamber by the eddy currents generated by the rotation of the impeller. The suspended particles themselves do not generate energy, but exchange energy with the liquid in the flow channel. In the flow process, suspended particles or long fibers do not come into contact with the blades, and the blades are often worn out in a relatively light condition. There is no case where the clearance is increased due to abrasion. In the long-term operation, no serious drop in efficiency occurs. The impeller type pump is suitable for pumping media containing large particles and long fibers. From a performance point of view, the efficiency of the impeller is relatively low, which is equivalent to only about 70% of that of an ordinary closed impeller, and the head curve is relatively flat.
3. Closed impeller: This type of impeller has higher normal efficiency. In the long-term operation, the condition is relatively stable, and the axial force of the pump using this type of impeller is small, and the secondary vanes can be set on the front and rear cover plates. The secondary vanes on the front cover can reduce the vortex losses at the inlet of the impeller and the wear of the particles on the seal ring. The secondary vanes on the rear cover not only serve to balance the axial force, but also prevent the suspended particles from entering the mechanical seal cavity to protect the mechanical seal. However, this type of impeller has poor non-blocking properties and is easy to wind. It is not suitable for pumping long-fiber-containing sewage media that have been treated.
4. Flow channel impeller: This type of impeller is a bladeless impeller. The impeller flow channel is a curved flow channel from the inlet to the outlet. Therefore, it is suitable for pumping media containing large particles and long fibers. Good blocking resistance. From the performance point of view, the high efficiency of this type of impeller is not much different from that of the ordinary closed impeller, but the head curve of this type of impeller pump drops steeply. The power curve is relatively stable, and it is not easy to generate super power. However, the cavitation performance of this type of impeller is not as good as that of an ordinary closed impeller, and it is particularly suitable for use in pumps with pressure inlet.
5. Spiral centrifugal impeller: The blades of this type of impeller are twisted spiral blades that extend axially from the suction inlet on the tapered hub body. The pump of this type of impeller has the function of a volumetric pump and a centrifugal pump. When the suspended particles flow through the blades, they do not hit any part of the pump, so the losslessness is good. Destructive to the delivery of small. Due to the propelling effect of the spiral, the suspension particles have a strong passability. Therefore, the pump with this type of impeller is suitable for pumping media containing large particles and long fibers, as well as high-concentration media. It has obvious characteristics when it has strict requirements for the destruction of the transmission medium.
In terms of performance, the pump has a steep drop in the head and the power curve is flat.
Sewage sewage pump used in the pressure chamber is a common volute, built-in submersible pumps used more radial guide vanes or runners. Volute spiral, ring and intermediary three. Helical scrolls are basically not used in sewage pumps. The annular pressure water chamber is easy to manufacture because of its simple structure. It is used in small sewage pump. However, due to the emergence of intermediate (half-helical) pressure chambers, the application range of annular pressurized water chambers gradually becomes smaller. Due to the intermediate pressure chamber, it has both the high efficiency of the spiral and the high permeability of the annular pressure chamber. Has been more and more attention by manufacturers.
In summary, regardless of whether any series of sewage sewage pumps is just a combination of different types of impellers and different types of pressurized water chambers according to the requirements of the transmission medium and installation, as long as the impeller and the pressure chamber can be optimally configured. Pump performance will be guaranteed.