Swing Check Valve, Water check valve

Product Overview

The Rubber Flap Check Valve is a non-return valve that automatically opens and closes by the flow of the medium itself. Its core component is a integrally molded reinforced rubber flap. Compared with traditional metal hinged check valves, it utilizes the flexibility and self-sealing characteristics of rubber to achieve extremely low opening pressure, slamming-free closure, and zero-leakage sealing. With a simple structure and no vulnerable moving parts, this valve is particularly suitable for pipeline systems containing impurities, corrosive media, or requiring frequent start/stop cycles. It is a cost-effective and reliable anti-backflow solution for municipal, industrial, and agricultural applications.

Product Structure

The Rubber Flap Check Valve mainly consists of the following parts:

1. Body: Cast iron or ductile iron, lined with rubber for excellent corrosion resistance.
2. Rubber Flap (Disc): Integrally molded rubber plate reinforced with high-strength nylon cord, pivoting around a top shaft.
3. Full Rubber Sealing Face: The flap itself acts as the sealing surface, mating with a metal or rubber seat in the body.
4. Pin Shaft & Optional Counterweight: Corrosion-resistant pin shaft; some large-diameter models include a built-in counterweight or spring-assisted closing.

The overall structure is simple and compact, with no vulnerable metal hinges, and the fluid passage is a full-bore straight-through design.

Function

1. Prevents Backflow: Forward pressure pushes the rubber flap open; when flow stops or reverses, the flap quickly returns to its seat under its own weight and backpressure, providing tight sealing.

2. Low Opening Pressure: The flap is light and flexible, requiring only about 0.005–0.01 MPa forward pressure to open, reducing energy loss.

3. Slamming-Free Closure: Excellent rubber elasticity provides flexible seating, significantly reducing water hammer impact and closing noise.

4. Zero Leakage Sealing: Under reverse pressure, the rubber flap fits tightly against the seat, achieving drip-tight sealing.

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Working Conditions

1. Applicable Media: Water, sewage, raw water, seawater, weak acid/alkali liquids, slurry, oils (appropriate rubber material required).

2. Temperature Range: Typically -10°C to +80°C (EPDM up to +120°C, NBR suitable for oils).

3. Installation Position: Horizontal or vertical pipeline (flow upward from bottom); horizontal installation is recommended.

4. Typical Applications: Municipal water supply & drainage, wastewater treatment plants, industrial recirculating cooling water, irrigation pumping stations, mine drainage systems, pump discharge anti-backflow.

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Summary

The Rubber Flap Check Valve, with its notable advantages of all-rubber flap, straight full-bore design, low opening pressure, and slamming-free closure, has become an economical and reliable solution for anti-backflow applications in water supply & drainage, sewage treatment, and industrial systems. It overcomes the water hammer and noise issues common to traditional metal check valves, adapts well to media containing impurities or corrosive substances, and requires minimal maintenance. For pipeline systems demanding long service life, zero leakage, and low energy consumption, the Rubber Flap Check Valve is an ideal choice.