Valve and actuator

摘要

A valve made from substantially all plastic parts that has integrally molded valve seats. A unique valve disk comprises two identical, mirror-image, molded plastic parts. The parts are of thin-walled construction but are joined together to give the valve body a substantially thick cross section with elongated shear surfaces in the radial direction. End flanges on the seal disk parts mechanically trap the soft sealing material and provide the maximum depth along the force line of contact between the sealing seat and the seal disk. The valve body has a cylinder and a cylinder cap of identically molded, mirror-image parts which house a diaphragm that overlies a plastic domed piston. The domed piston is provided with radially spaced circular ribs for supporting the diaphragm against excess deflection.