Page 6 of Check Valve Manufacturer, Industrial Check Valves Supplier China

Check Valve

The ANSI swing check valves provided by Weldon are cast steel check valves in which the disc swings on a hinge or trunnion to block the flow, either onto the seat to block reverse flow or off the seat to allow forward flow. The seat opening cross-setcion may be perpendicular to the centerline between the two ports or at an angle. Although swing check valves can come in various sizes, large check valves are often swing check valves. ANSI Check valves mainly follow American Standards, including API 6D, ASME B16.34, ASME B 16.5, ASME B16.10, etc.
 
The DIN swing check valves have reasonable structure, reliable sealing and small open-close torques. DIN swing check valves are designed according to DIN 3356 standard, product range covers nominal pressure PN16 - PN160, working temperature -29 - 350°C, carbon steel, stainless steel, alloy steel and other materials, widely used in petrochemical, chemical, electric steel, natural gas and other fields.
The Pressure seal bonnet (PSB) check valves provided by Weldon are adopted for high pressure service. Compared to Bolted Bonnet (BB) check valve, which the body flange and bonnet flange are joined by studs and nuts, when the system pressure increases, the potential for leakage through the body / Bonnet joint also increases, the unique structure of the pressure seal Bonnet is that the body-Bonnet joints seals improves as the internal pressure in the PSB check valve increases, the higher the internal pressure, the greater the sealing force.
 
Due to wafer shaped design, The Wafer check valves provided by Weldon are thinner and lighter than the conventional check valves. Similar in operation to a swing check valve, the wafer check has a solid disc and seat arrangement that performs the check action. Wafer check valves can be mounted in vertical or horizontal diretcions.
Weldon wafer check valve offers easy assembly and maintenance as well as quick open and close. Single disc wafer, dual wafer, axial flow, quick opening and slow closing action with damping check are available based on different request of service.