Abstract: In accordance with an illustrative embodiment of the present invention, a seal structure that provides a leak-proof metal-to-metal seal against an opposing seal surface includes an annular body having an inwardly directed flange and an outwardly directed flange, each flange having a seal foot on the outer portion thereof. The inner foot engages the seal surface first and produces elastic bending of the inner flange as a cantilever beam, together with a rotation of the annular body which reduces the gap below the outer seal foot to zero. Then as the seal structure is forced further against the seal surface, a counter-rotation is applied to the body to correct the first-mentioned rotation, and the lower end face of the body engages the seal surface to provide a limit stop. Internal fluid pressures produce additional sealing forces that vary in proportion to such pressures.

Abstract: A valve mechanism according to the present invention incorporates at least one movable valve seat that is received within a seat pocket of the valve body and establishes sealing engagement with a movable valve element. An annular universal seat spring formed of a material such as standard carbon steel is deformed from a generally flat configuration to a frusto-conical configuration during assembly of the valve and exerts a force urging the valve seat against the valve element. Depending upon the depth of the seat pocket, the length of the valve seat and the size or thickness of the valve element, the seat spring will be deformed within its elastic limits or beyond the elastic limits of the material thereof, whereupon it will take a permanent set. In either case, the seat spring compensates for tolerance variations and exerts a spring force within a preselected narrow force range to ensure effective sealing capability and low torque operation.

Abstract: There is disclosed a seal assembly for sealing between the body of a valve and the closure member thereof, as well as a method for mounting the assembly within an annular groove with the body which surrounds the flowway through one side of the valve. The seal assembly comprises inner and outer seal rings of relatively hard and soft material which are locked within the groove by a resin which has hardened in the groove as the rings are held in predetermined endwise positions therein.

Abstract: A valve has upstream and downstream seat assemblies each having a pair of spaced annular face seals in concentric relation to form inner and outer face seals. A movable valve member (26, FIG. 2; 88, FIG. 8) has a main bore therethrough and is mounted in a valve chamber between the seat assemblies for movement between open and closed positions. A pair of auxiliary fluid passageways (72, 74, FIG. 2; 112, 114, FIG. 8) are located in the valve member at opposite ends of the main bore. Each of the auxiliary passageways has its outer end opening to the side of the valve member radially outward of the main bore and an inner end opening into the main bore.

Abstract: A valve seal includes inner and outer concentric seal rings located side by side in a groove with the inner seal ring against the groove inner wall and the outer seal ring against the groove outer wall. Interfitting surfaces are provided on the seal rings to hold them together and prevent longitudinal movement between them. The groove and the seal rings cooperate to hold the seal rings in the groove. One of the seal rings is relatively soft and has good low pressure sealing characteristics while the other seal ring is relatively hard and has good high pressure sealing characteristics.

Abstract: A packing assembly is arranged between a gate valve stem connected to an actuator and a bonnet secured to the valve body. An externally threaded packing sleeve is threaded within the bonnet and has the packing assembly removably connected thereto for movement with the sleeve. The packing sleeve has an outer end portion which extends into an easily disassembled actuator body where it is easily accessible to a removal tool for replacing the packing. The valve stem has a beveled shoulder thereon which engages a flexible inner flange on the bonnet in the closed position of the gate valve to provide a tight metal-to-metal surface contact between the shoulder and flange.

Abstract: A flange joint for a valve body and the associated bonnet has a planar flange sealing surface around the body opening and a mating flange around the bonnet. The valve body flange has a raised portion around an inner portion extending above a planar sealing surface. The bonnet flange has a substantially rigid outer portion and a deflectable inner portion with a planar flange sealing surface on the exposed side thereof. The deflectable portion contacts the body flange raised portion in sealing contact and is deflected as the flange sealing surfaces are brought together by fasteners. The bonnet member deflectable portion maintains a seal around the valve body flange in the event the fasteners relax under high temperature conditions or high pressure.

Abstract: A valve comprised of a valve body having a body with flow passages therethrough and a valve member mounted therein movable between open and closed positions. An annular groove in the body around a flow passageway has an open end, a closed end, and a pair of divergent side walls with the groove width at the closed end portion being greater than the width at the open end. An annular seal is positioned in the groove. A chemical fastener in the groove secures the seal ring in the groove. A method of making the valve seal structure includes forming the groove with divergent side walls in a seal ring supporting position of a valve body and then partially filling the groove with a chemical fastener material. The seal ring is inserted into the groove within the chemical fastener material and the chemical material is cured to secure the seal ring in the groove.

Abstract: A pair of seat ring members are loosely mounted in annular recesses around the longitudinal bore in a gate valve body at the intersection of the bore and the valve chamber on opposite sides of the gate member. Each of the seat ring members has a rear face comprised of a pair of stepped portions connected by an outwardly facing annular surface portion. Each seat ring has a groove at the juncture of the outer stepped surface portion and the outwardly facing annular surface. A seal ring chamber is formed between the recess annular wall, the stepped outer surface portion, the outwardly facing annular surface and the groove. A resilient O-ring is positioned in the seal ring chamber. The O-ring has a sufficient cross section to seal between the recessed end wall and the outwardly facing annular surface when initially positioned in the seal ring chamber upon assembly of the valve.

Abstract: A gate valve structure having a valve body with a body recess therein surrounding the valve bore and an annular floating seat member or ring in the body recess for contacting a gate member. The seat ring has an annular groove around a mid-portion of its outer periphery with a resilient sealing member mounted therein. The body recess is defined by a pair of radially stepped wall portions having different diameters and joined by an abutment. The seat ring has a pair of complementary stepped outer peripheral portions facing the wall portions with the groove being positioned between the stepped portions of the seat ring. The seat ring is positioned in the recess and the annular resilient sealing member between opposed sides of the groove is compressed between the abutment on the valve body and an opposed side of the groove in the seat ring to provide sealing between the seat ring and the body and to resiliently urge the seat ring toward the gate member.

Abstract: A valve comprised of a valve body having a body with flow passages therethrough and a valve member mounted therein movable between open and closed positions. An annular groove in the body around a flow passageway has an open end, a closed end, and a pair of divergent side walls with the groove width at the closed end portion being greater than the width of the open end. An annular seal is positioned in the groove. A chemical fastener in the groove secures the seal ring in the groove. A method of making the valve seal structure includes forming the groove with divergent side walls in a seal ring supporting position of a valve body and then partially filling the groove with a chemical fastener material. The seal ring is inserted into the groove within the chemical fastener material and the chemical material is cured to secure the seal ring in the groove.