Patent ID: 8794595

Claim:
A diaphragm valve, comprising: a bonnet assembly; a valve body; an internal flow pathway; a compressor; a two-piece flexible diaphragm comprising a flexible shield and a flexible backing, the flexible shield having a peripheral shield region and a flexible central region, and the flexible backing having a peripheral backing region and a flexible central backing region; a seal plate comprising an aperture circumscribed by a closed path; one or more fasteners for securing the flexible shield, the flexible backing and the seal plate between the bonnet assembly and the valve body so that the closed path of the seal plate lies between the peripheral shield region and the peripheral backing region; wherein, the closed path of the seal plate prevents the peripheral shield region from flowing into the peripheral backing region despite compressive forces exerted on the peripheral shield region by operation of said one or more fasteners; wherein, upon activation of the compressor to open or close the internal flow pathway, both the flexible central shield region of the flexible shield and the flexible central backing region of the flexible backing will flex above and below the plane of the aperture of the seal plate in proportion to the travel of the compressor; a substantially enclosed interstitial void located between the flexible central shield region and the flexible central backing region; a fluid located within the substantially enclosed interstitial void; a port connector located on an outward-facing surface of the closed path of the seal plate; and an access port passing through the closed path of the seal plate to fluidly couple the substantially enclosed interstitial void to said at least one port connector; wherein said port connector is configured to provide an interface to a breach detector that will detect a deviation in a property associated with the fluid located within the substantially enclosed interstitial void; and wherein the access port does not pass through a wall of the flexible shield or the flexible backing.