The check valves
provided by Weldon mainly include Swing check valve
, Pressure sealed cover check valve
, Wafer check valve
, etc. Check valve
, also called non-return valve
, is mainly installed on the pipeline, allowing the medium to flow in only one diretcion.
Weldon check valves
offer simple structure, less parts, convenient maintenance and repair and low failure rate. The full open disc design is applied to provide a larger opening flow area after disc opening, small fluid resistance and large valve flow coefficient. Counter weight or damp structure can be applied to reduce the impact of water hammer while disc opening.
Size: 2 Inch - 60 Inch (DN50 - DN1500)
Pressure Rating: Class 150 LB - 2500 LB (PN16 - PN420)
Material: Carbon steel, Stainless steel, Alloy steel, including WCB, GS-C25, LCB, LCC, LC1, LC3, CF8, CF8M, CF3, CF3M, WC6, C5, C9, C12, 4A, 5A, MONEL, ALLOY20, C95800
Connetcion End: BW, RTJ, Flanged.
Design & Manufacture Standard: API 6D
, DIN 3352
, BS 1868
Test Standard: API 598, EN 12266.
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
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.