Product Overview of the WZ Self-Priming Sewage Pump (Third Generation)

The WZ self-priming sewage pump (third generation) represents a major leap forward from the original ZW model. Building on the ZW platform, it features a more compact design, improved start-up performance, and the ability to operate without a foot valve—requiring only a single priming operation. Its flow passages can handle small solid particles (though it is not suitable for fibrous materials). Pump casings are available in cast iron, cast steel, and stainless steel; impellers come in cast iron, aluminum, copper, and stainless steel; and mechanical seals are offered in ceramic, graphite, PTFE, hard alloy, and silicon carbide. When paired with an automatic liquid-level control cabinet, the pump can automatically start and stop according to the desired liquid level, providing fully automated control. It is widely used in industrial, agricultural, and research settings for pumping and conveying liquids.

Advantages of the WZ Self-Priming Sewage Pump (Third Generation)

1. Strong wastewater discharge capability: A specialized impeller anti‑clogging design ensures the pump operates efficiently and remains free of blockages.

2. High efficiency and energy savings: Utilizing an advanced hydraulic design, its efficiency is 3–5% higher than that of conventional self-priming pumps.

3. Excellent self-priming performance: The self-priming lift is 1 meter higher than that of conventional self-priming pumps, and the self-priming time is shorter.

4. Integrates self-priming and clog‑free sewage discharge into a single unit, employing an axial‑flow, external‑mixing design. It offers reliable self‑priming performance, strong sewage‑discharge capacity, high efficiency and energy savings, and convenient operation and maintenance.

5. Compact design, excellent start-up performance and self-priming capability; no foot valve required, no priming water needed; the pump passage can handle solids up to 12 mm in size.

Application Scope of the WZ Self-Priming Sewage Pump (Third Generation)

1. Ambient temperature less than 50°C, medium temperature less than 80°C.

2. The pH range for cast iron is 6–9; for stainless steel, it is 2–13.

3. The medium management density shall not exceed 1250 kg/m³.

4. The self-priming height must not exceed the specified limit, and the suction pipe length should be less than 10 meters.

This pump employs an external‑mix axial recirculation impeller design. The pump casing comprises a suction chamber, a storage chamber, a volute, a return‑water passage, and an air–water separation chamber. Upon startup, under the action of centrifugal force, the residual water in the suction chamber and the water from the inlet pipeline are routed through the return‑water passage back into the pump impeller, where they once again mix with the air in the inlet line. This arrangement prevents backflow‑induced impact on the impeller during shutdown, which could otherwise cause the motor to reverse rotation.