Like other pumps, the impeller and pressure chamber are the two core components of the sewage pump. The quality of its performance also represents the quality of pump performance, including the anti clogging performance, efficiency, cavitation performance, and anti wear performance of sewage pumps If it is ensured by two major components: the vane pump and the pressure chamber. Below is an introduction:
1. Impeller structure type: The impeller structure is divided into four categories: blade type (open, closed), swirl type, flow channel type, (including single channel and double channel) spiral centrifugal type. The open and semi open impeller is easy to manufacture, and when inside the impeller When blockage is caused, it can be easily cleaned and repaired, but in long-term operation, under the erosion of particles, the gap between the blades and the sidewall of the pressurized water chamber will increase, thereby reducing efficiency. And the increase in clearance will damage the pressure difference 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 increase in clearance, the stability of the liquid flow state in the flow channel is damaged, causing the pump to vibrate. This type of impeller is not easy to transport large particles and long In terms of performance, this type of impeller has low efficiency in terms of fiber medium, with a flow rate of about 92% that of a regular closed impeller, and a relatively flat head curve.
2. Swirl impeller: For pumps using this type of impeller, due to partial or complete contraction of the impeller from the flow channel of the pressurized water chamber. So it has good non clogging performance, strong particle passing ability and long fiber passing ability. The flow of particles in the pressurized water chamber relies on the impeller Driven by the vortex generated by rotation, the 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 wear of the blades is relatively mild There is a situation where the gap increases due to erosion, which will not cause a serious decrease in efficiency 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 Equivalent to about 70% of a regular closed impeller, 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, and the axial force of the pump using this type of impeller is relatively small, and auxiliary blades can be set on the front and rear cover plates. The auxiliary blades on the front cover plate can To reduce the vortex loss at the impeller inlet and the wear of particles on the sealing ring. The auxiliary blades on the rear cover plate not only balance the axial force, but also prevent suspended particles from entering the mechanical seal chamber and protect the mechanical seal. But this type The impeller has poor blockage free performance and is easy to wrap, making it unsuitable for pumping untreated sewage media containing large particles (long fibers).
4. Flow channel impeller: This type of impeller belongs to the impeller without blades, 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 resistance to blockage. From a performance perspective The efficiency of this type of impeller is not significantly different from that of a regular closed impeller, but the head curve of the impeller pump with this type is relatively steep. The power curve is relatively stable and is not prone to generating excessive power, but the cavitation performance of this type of impeller is not as good as that of a regular closed impeller.
