Below is a list of Plastic Diaphragm Valves manufacturers from Spartanburg, South Carolina. Plastic diaphragm valves are process stream regulation devices that use an elasticized polymeric membrane to transect conduits either fully or partially to maintain optimal flow and pressure rates. Included in this material category are those diaphragm valves made entirely of plastic components as well as those that employ plastic elements in conjunction with metal parts and forms.