EN 12334 Weighted Swing Check Valve | Swing Check Valve with Weight & Lever

At Metalsin, we supply weighted swing check valves that are made in accordance with EN 12334. The weighted swing check valve, also known as swing check valve with weight & lever, is a specialized type of check valve designed to prevent backflow with enhanced control over closure dynamics.

Structural Features

A typical EN 12334 weight swing check valve, made of ductile iron EN-GJS-450-10, with weight & lever, double flanged, resilient seated.

The EN 12334 weighted swing check valve consists of some key components: (1) Body: Typically made of spheroidal graphite cast iron (duction iron) in accordance with EN 1563, housing internal components. (2) Disc: A hinged ductile iron gate that opens or closes the flow path, often lined with EPDM rubber to form resilient-seated sealing. (3) Hinge/Pivot: Allows the disc to swing freely; positioned to optimize fluid dynamics. (4) Lever Arm: Attached to the disc, extending outward to amplify mechanical force. (5) Adjustable Weight: Mounted on the lever arm to modulate closing force and speed. (6) Seat Ring: A metal ring with stub that is inserted into the body providing the seating surface for tight closure upon contact with the disc. The seat ring is generally made of bronze, brass, or stainless steel.

Function Principle & Applications

In the EN 12334 weighted swing check valve, fluid pressure pushes the disc open against the resistance of the weight. The lever arm magnifies the weight’s effect, allowing precise control over the opening. As flow diminishes or reverses, the weight accelerates disc closure via gravitational force, preventing sudden slamming. This mitigates water hammer—a pressure surge caused by abrupt valve closure. The weight’s position on the lever can be modified to tailor closing speed and force, adapting to varying flow conditions.

Typical drawing of weighted swing check valve (with weight & lever), ductile iron, double flanged, made to EN 12334, for waterworks applications.

The weight and lever swing check valve offers effective backflow prevention with water hammer mitigation through controlled closure, customizable operation via adjustable weights, and durable construction for high-pressure and large-diameter pipelines. They are widely used for the following applications: (1) Water/Wastewater Systems: Prevents backflow in municipal pipelines, irrigation, and treatment plants. (2) Pump Discharge Lines: Protects pumps from damage due to reverse flow after shutdown. (3) HVAC Systems: Manages coolant flow in heating/cooling circuits. (4) Fire Protection: Critical in sprinkler systems to maintain pressure and prevent contamination.

Technical Specifications

Depending on users’ requirements, EN 12334 weight swing check valves may be furnished in rubber lined or metal seated type. Working pressure: PN10 / PN16; working temperature: -10°C~100°C; flanged ends made to EN 1092-2; fusion epoxy bonded (FBE) coating in accordance with AWWA C550; meeting EN 1074-1 & EN 1074-3 for water supply service.