Wastewater Centrifugal Diesel Self-priming Pump

The Wastewater centrifugal diesel self-priming pump The ZW type self-priming non-blocking sewage pump is developed based on the structure and performance of the ZX type self-priming centrifugal pump and the QW type submersible sewage pump. It incorporates the advantages of similar foreign products and is a new type of pump that combines self-priming and sewage discharge functions. It can suck up substances such as large solid particles with a diameter of 60% of the outlet diameter, fibers with a length of 1.5 times the impeller diameter, waste minerals, fecal matter, and all kinds of engineering sewage and gel-like liquids. This significantly reduces the labor intensity of human workers, and is also convenient for installation and use.

The Wastewater centrifugal diesel self-priming pump

· Strong sewage discharge capacity: The special impeller anti-blockage design ensures that the pump operates efficiently without any blockage.
· High efficiency and energy saving: Utilizing an excellent hydraulic model, its efficiency is 3-5% higher than that of ordinary self-priming pumps.
· Excellent self-priming performance: The self-priming height is 1 meter higher than that of ordinary self-priming pumps, and the self-priming time is shorter.

The core function of the zw self-priming sewage pump is "self-priming", meaning it can start and complete the water suction process without the need for additional water filling. Its working principle is based on the mixture and separation of gas and liquid. There is a water storage chamber inside the pump. During the first use, a small amount of liquid needs to be injected as a priming fluid. After starting, the impeller rotates at high speed, mixing the air and liquid in the pump to form an air-liquid mixture. Then, it passes through the separation chamber to discharge the air and form a negative pressure, thereby achieving continuous water suction. This design makes it stable in frequent start-stop or intermittent operations.
In contrast, ordinary centrifugal sewage pumps usually require a bottom valve or a water filling device to assist in starting. If there is air in the suction pipeline, it is prone to cause insufficient suction height or failure to operate normally. However, the zw self-priming sewage pump avoids this drawback, especially suitable for scenarios where the water source is unstable or the installation conditions are limited.

Wastewater centrifugal diesel self-priming pump

The main components of the zw self-priming sewage pump include the pump body, impeller, mechanical seal, and motor, etc. Its design features are as follows:
- Double volute structure: The pump body adopts a double-flow channel design, which can reduce hydraulic loss and improve efficiency.
- Wear-resistant impeller: The impeller material is mostly cast iron or stainless steel, which has good tolerance to particles in the sewage.
- Axial seal: Mechanical seal or packing seal is used to prevent sewage leakage and extend the service life.
Compared with submersible sewage pumps, the zw self-priming sewage pump does not need to work underwater, so the motor part is not affected by water pressure, and maintenance is more convenient. However, submersible sewage pumps have lower noise because they are completely submerged, and are suitable for environments with high requirements for quietness. Both have their advantages and disadvantages, and the choice should be based on actual needs.

The typical applications of the self-priming sewage pump include:
Agricultural irrigation: Pumping water from ditches or ponds, especially suitable for areas with fluctuating water levels.
Industrial drainage: Treating wastewater containing fibers and sand, such as in food processing and paper manufacturing industries.
 Emergency drainage: Removing water accumulation in construction sites or basements, as the self-priming function allows for quick deployment.
It should be noted that if the sewage contains corrosive chemical substances or hard particles (such as metal shavings), a pump body made of special materials or a filtering device should be selected; otherwise, it may affect the lifespan of the pump.

1. The ambient temperature shall not exceed 50℃, and the medium temperature shall not exceed 80℃. Special requirements can reach up to 180℃.
2. The pH value of the medium: cast iron material is 6-9 grade, stainless steel is 2-13.
3. The specific gravity of the medium shall not exceed 1240 kilograms per cubic meter.
4. The self-priming height shall not exceed the specified value of 4.5-5.5 meters, and the length of the suction pipe shall be ≤ 10 meters.
5. The passing capacity: the suspended particle diameter is 60% of the pump diameter, and the fiber length is 5 times the pump diameter.

The ZW series self-priming non-blocking sewage pump is mainly composed of the pump body, impeller, rear cover, mechanical seal, pump shaft, bearing seat, inlet valve, gas-liquid separation pipe, water replenishment valve, inlet and outlet pipes, etc. The structure of the pump is shown in the figure.
The working principle of the pump: There is a liquid storage chamber in the pump body, and it is connected with the working chamber of the pump through the upward return hole at the top and the downward circulation hole at the bottom, forming an axial external-mixing system with the pump. After the pump stops working, a certain volume of liquid has been stored in the pump chamber. When the pump is started, the liquid in the pump chamber and the air inside are thrown upward under the action of the impeller, and the liquid flows back to the working chamber through the grid of the gas-liquid separation pipe, while the gas is discharged outside the pump, creating a certain vacuum inside the pump, achieving the self-priming effect.