摘要 |
A low pressure back-check valve comprising a valve housing with a fluid inlet and outlet, a valve seat, and a dual disc valve element normally biased into closed position against the valve seat by mechanical support structure within the housing. One of the dual discs is made of pure gum rubber and/or like material, while the other disc is made of semi-rigid plastic material, such as unplasticized Polyvinyl Chloride (PVC). The mechanical support structure includes a pair of pins spaced 180 DEG apart. While these pins constantly hold the dual discs in biased position against the valve seat, because of the compliant construction of the dual discs, the valve can open under a very low pressure, such as 0.02 pounds per square inch.
|