Weflo Fig. 5306 Wafer Double Door Check Valve

Overview

The Weflo Fig. 5306 is a wafer-pattern double door check valve that prevents reverse flow in pumped water systems while occupying only a fraction of the length of a conventional swing check valve. Two spring-assisted plates hinge on a central pin and close quickly as forward flow falls, and a soft seal gives tightness even at low differential pressure. Weflo states that the Weflo Fig. 5306 complies with BS EN 12334, is WRAS Approved with EPDM seats for potable water, and is certificated to ANSI/NSF 61 and 372 for DN50 to DN1200, with a rated working pressure of 25 bar (300 psi).

Seven Star LLC supplies the Weflo Fig. 5306 to HVAC contractors, pump packagers and water infrastructure projects in Oman and the GCC, with engineering support in Muscat. For engineers specifying a WRAS approved check valve or a compact non-return valve for chilled water pump discharges, the Weflo Fig. 5306 datasheet provides the standards and material data needed for approval.

Operating Principle

In a dual plate check valve, the flow area is divided into two half-moon openings, each covered by a lightweight plate. Forward flow pushes the plates open against a torsion spring; when flow slows down, the spring starts closing the plates before the flow actually reverses. This spring-assisted action is what the datasheet refers to as better dynamic behaviour, and it reduces the reverse velocity at the moment of closure, which in turn limits slam and pressure surge when a pump stops.

Once closed, the plates bear on a resilient seat, giving a tight seal even when the back pressure is small. As general engineering guidance, the short travel and low mass of the plates make the Weflo Fig. 5306 well suited to pump discharge lines in parallel pumping arrangements, where a fast-closing check valve stops flow from one running pump circulating backwards through a stopped standby pump.

Engineering Design of the Weflo Fig. 5306

The standard body of the Weflo Fig. 5306 is grey cast iron EN-GJL-250 (ASTM A126 Class B), with a ductile iron body available and supplied as standard for the 25 bar / 300 psi rating on DN350 and larger. Discs are stainless steel X5CrNi18-10 (ASTM A351 CF8), the seat and gasket are EPDM or NBR rubber, hinge pin, stop pin and pin retainer are 304 stainless steel, the spring is stainless steel 302 and the washer is PTFE. Corrosion protection is liquid epoxy paint or fusion bonded epoxy powder coating (FBE) internally and externally.

The wafer body is clamped between flanges to EN 1092-2 PN10 or PN16 or ANSI B16.1 Class 125, and Weflo publishes outside diameters to suit Table D/E, ANSI 125/150, EN 1092-2 PN16 and PN25 flanges. Face-to-face lengths range from 43 mm at DN40 to 222 mm at DN600, so the Weflo Fig. 5306 saves considerable space and weight compared with flanged swing check valves. For sizes DN200 to DN400 the datasheet also lists the number and radius of the locating notches around the body, marked N-R on the drawing.

Key Features

The following features are stated on the Weflo Fig. 5306 datasheet.

• The valve complies with BS EN 12334 for cast iron check valves.
• A short face-to-face dimension and compact design allow installation and service in tight spaces.
• Spring assistance gives better dynamic behaviour and quick closure.
• A soft seal provides tightness even at low differential pressure.
• It is WRAS Approved with an EPDM seat for potable water.
• ANSI/NSF 61 and 372 certification applies to DN50 to DN1200.
• It suits flanges to EN 1092-2 PN10 or PN16 and ANSI B16.1 Class 125, with other drillings on request.
• The rated working pressure is 25 bar / 300 psi.

Industrial Applications

The most common location for the Weflo Fig. 5306 in building services is the discharge of chilled water, condenser water and domestic water booster pumps, where it protects pumps from reverse rotation and keeps the system full when a pump stops. It is also used on cooling tower make-up lines, fire and irrigation water transfer pumps, and the outlets of potable water tanks feeding residential and commercial towers. Because the valve is short and light, it is popular in compact pump rooms of hotels, hospitals and malls in Muscat and other GCC cities.

Seven Star LLC supplies the Weflo Fig. 5306 for HVAC, water supply and industrial cooling projects throughout Oman, including Sohar and Salalah, and helps buyers choose seat material and flange drilling. It is often installed on pump sets such as the Grundfos Hydro MPC booster set and the Wilo-Helix V vertical multistage pump, together with isolation valves such as the Keystone Figure 990/920 butterfly valve.

Technical Specifications

Weflo Fig. 5306 values are taken from the Weflo datasheet and should be confirmed for the final order.

Selection and Installation Notes

The points in this section are general engineering guidance for dual plate check valves and are not Weflo instructions. Install the valve with the flow arrow in the direction of flow and orient the hinge pin vertically in horizontal pipework, so both plates open and close evenly. Allow several pipe diameters of straight pipe downstream of pumps, elbows and reducers where possible, because turbulent flow can cause plate flutter and premature wear of the hinge and springs.

Check that the plates will clear adjacent butterfly valves or reducers when fully open, as the plates project beyond the wafer body. For potable water services, specify the EPDM seat to match the WRAS approval stated on the datasheet, and Seven Star LLC can provide the Weflo Fig. 5306 documentation with the submittal.

How to Order

To obtain a quotation for the Weflo Fig. 5306, send Seven Star LLC an RFQ with sizes, flange drilling, seat material and service conditions. Our engineering team in Muscat can confirm availability and lead time, share the Weflo technical datasheet available for download on this page, and support pump room and water projects across Oman and the GCC.