Pressure loaded sealing arrangement

A valve comprising, in combination, a first element constituting a valve body defining a flow passage extending therethrough, a second element constituting a flow control member movably supported relative to said body for movement between an open position and a closed position for opening and closing said flow passage, one of said elements defining an annular sealing surface, the other of said elements defining an annular seal ring support groove oriented to confront said sealing surface in close proximity thereto;

• an annular seal ring member disposed in said support groove, said seal ring member, in section, including a first leg portion providing an annular anchoring flange, and a second leg portion including, an intermediate section extending in a direction toward said sealing surface as a continuation of said first leg portion, a reverse bent, bight segment of an arcuate shape joined to said intermediate section and extending radially outward of said support groove, said bight segment being joined with a free end segment which extends into said support groove oppositely of said intermediate section and spaced from said intermediate section, and lip means formed on said free end interiorly of said support groove and extending transversely thereof in a direction away from said intermediate section of said second leg portion, such that said bight segment and said free end segment serve to define with the remainder of said second leg portion and interior plenum chamber;
• said seal ring support groove including a first section for receiving said anchoring flange in fixed engagement therein, and a second section within which said second leg portion is disposed with said bight segment extending from said seal ring support groove for confronting sealing engagement with said annular sealing surface, said second section of the seal ring support groove being defined by spaced apart side surfaces, one of said surfaces defining shoulder means extending axially inward of said groove upon which said transversely extending lip means is engaged to maintain the free end of said second leg portion in said groove and to define the limit of the extension of said bight segment from said support groove, said bight segment extending from said groove a sufficient distance such that upon the engagement of said bight segment with said annular sealing surface upon movement of said flow control member to the valve closed condition, said second leg portion will be moved inwardly of said annular seal support groove to disengage said lip means from said shoulder means a sufficient amount to allow line fluid to enter said seal support groove and said plenum chamber, thereby to pressurize said seal, said sealing surface on said one element being disposed in close proximity to said confronting support groove in said valve closed condition, with the side surface of said support groove opposite said side surface having the shoulder means formed thereon, being disposed to form with said sealing surface an annular substantially right angle caulking corner, such that due to the close proximate of said sealing surface and said groove, and the provision of said caulking corner, upon said seal being pressurized, line pressure will force said bight segment into said caulking corner, with portions of said bight segment being forced into sealed engagement with said side surface and sealing surface defining said annular caulking corner, and means providing one or more passageways connecting the interior of said second section of said ring support groove with said flow passage such that fluid can escape from said plenum chamber even though said lip is engaged with said shoulder means.