Abstract: A gate valve is disclosed having a secondary seal, wherein the gate forms a metal to metal seal with the seat and wherein a resilient seal is moved toward the gate in a closed position to form a secondary fluid-tight seal with the gate. A device for deenergizing the secondary seal is provided in order to prevent wear of the secondary seal upon opening of the gate and also to reduce the gate drag caused by the energized secondary seal. Also disclosed is a pressure relief mechanism for the secondary seal adapted to prevent damage to the seal and a mechanism for evenly applying opposing secondary seals.

Abstract: A seal device for a gate valve is disclosed, in which annular members facing the front and rear surfaces of a gate valve member having a through hole are coupled to a valve cage by inner and outer bellows, each of the annular members has an annular recess formed on the side facing the gate valve member and closed by an annular mirror surface finished thin plate secured by welding to an opening thereof, the individual bellows are elongated by fluid under pressure supplied into annular spaces defined by the inner and outer bellows, and the annular mirror surface finished thin plates are strongly urged against the gate valve member by the pressure of the fluid forced from the annular spaces into the annular recesses. Edge portions of the annular mirror surface finished thin plates are to be very firmly mounted to the annular members, and the mechanical strength of the thin plates is to be increased.

Abstract: A vacuum gate valve includes a spreading mechanism with an actuating member extending between first and second valve plates and movable transversely of the axis of the valve, and parallelepiped spreading members disposed between the first valve plate and the actuating member and between the second valve plate and the actuating member. In the open position of the valve, the spreading members include an acute angle with the direction in which the actuating member is moved for closing the valve. When the actuating member is moved in order to spread apart the valve plates and to close the valve, the spreading members pivot about intersecting lines of contact surfaces formed in the valve plates and in the actuating member. In the closed position of the valve, the spreading members extend perpendicularly to the direction of the movement of the actuating member.

Abstract: There is disclosed an expanding gate valve having seats which are press-fitted into annular recesses in the valve body on opposite sides of the gate, each seat including a ring having at least one annular rib on its outer end which is of a harder material than that of the inner end of the recess and embedded therein to form a pressure barrier between the seat and recess.

Abstract: An improved through conduit gate valve having a double expanding gate assembly with floating seats. The gate assembly carries at its edges flat guide strips which are slightly thicker than the collapsed thickness of the gate. These strips engage the seals to keep them from blinding or back wedging the gate assembly during movement between its opened and closed positions. Elastic suspension elements mount the strips to the gate assembly for proper wedging action by expansion against the seals but insures return into the collapsed position during the mentioned movement.

Abstract: A seal assembly is disclosed in connection with a valve, preferably a sliding gate valve. The seal assembly includes a retaining ring having a surface contour complementary to that on a resilient, replaceable seal element, in order to positively hold the seal in position during use. The ring also includes a threaded portion that may be received in a threaded section either in the valve body or in a separate valve seat collar secured within the valve body. In one embodiment, the seal includes an annular metallic component having an annular groove, into which a resilient component is secured.

Abstract: A valve (10) having an expansible gate assemblage of ported juxtaposed gate and segment members (18, 19) which are movable into sealing engagement with upstream and downstream valve seats (28) about the flow passage (12, 14) in the open and closed conditions of the valve wherein the valve includes pressure relief means which relieves excessive pressure in the valve chamber (11) into the upstream flow passage (12) when the environment in the chamber reaches a preselected temperature with the valve retaining capability of providing an upstream seal in the event of subsequent downstream leakage. The pressure relief means is installed in the segment member (19) of the gate assembly and comprises a passage (43) extending from the port (16) through the segment to the sealing face (25) of the segment member at a location which is exposed to the upstream flow passage (12) in the valve closed condition.

Abstract: A slide gate valve assembly is provided wherein resilient means exert positive pressure to force a solid slide gate against the periphery of an aperture to establish a tight seal for retaining dry bulk particulate material in a container. Cam means are provided in the assembly to release the positive pressure on the side gate which may thereupon be removed from the aperture to dump the contents from the container.

Abstract: To prevent pressure induced floating of the interference fitted seats of expanding gate valves, a seat ring body is provided which is press fitted within the upstream seat recess of a valve body. The seat ring body defines a sealing face of circular form which is disposed for sealing engagement with the segment portion of an expanding gate and segment assembly. The seat ring body also defines an axial extension tube extending upstream from the seat ring body with a circular sealing lip defining the outer periphery thereof being in radial sealing engagement with a reduced diameter portion of the seat recess. The radial extension is pressure yieldable to enhance the radial sealing capability thereof and defines a pressure responsive area that is equal to or less than the pressure responsive area of the sealing face.

Abstract: An expanding gate valve having a pressure-secured seat. The valve includes a valve body having a cavity formed therein and an inlet and outlet formed in the body, both of which intersect the cavity. A counterbore is formed about the circumference of both the inlet and the outlet at their respective intersections with the cavity. An annular seat having a rear surface and a front seat surface is received within the inlet counterbore. An annular seal is formed on the front seat surface and a second annular seal is disposed between the rear surface and the valve body. The front annular seal has a sealing diameter greater than the rear annular seal and an annular recess is formed on the front seat surface on the radially inward side of the annular seal. A second annular seat having a planar front seat surface is received within the outlet counterbore.

Abstract: An expanding gate valve with a valve seat structure which comprises a pair of "floating" seat rings (60) loosely received in annular seat pockets (52) surrounding the flow passage through the valve and each having an axial dimension which exceeds the depth of the seat pocket. The front face (61) of each seat ring is disposed adjacent the gate assembly (24, 26) and is provided with an annular groove (63) and an annular resilient sealing element (64) therein adapted to form a ring of sealing contact area about the flow passage (14) when the gate assembly is expanded thereagainst. The rear face (66) of the seat ring (60) is provided with an annular groove (63') and a second annular resilient sealing element (64'). The two annular sealing elements are coaxial and the inner diameter of the front sealing element (64) exceeds that of the rear sealing element (64') so that the front sealing element is a greater radial distance from the flow passage (14) than is the rear sealing element.

Abstract: A gate valve is disclosed having a casing with inlet and outlet apertures one of which has a valve seat. An actuator reciprocal transversely of the apertures is provided having two oppositely disposed faces. At least one plate member which serves as a valve head flanks at least one of the faces for cooperation with said valve seat. Cylindrical rotative means having a rectangular cross-section are positioned between the actuator member and the plate member for moving the plate member from an open to a closed/latched position as the actuator member is moved.

Abstract: Opening and closing of a fluid flow path is controlled by a valve closure member which consists of both a sealing plate and a counter element and which is moved within its own plane to open and close the valve assembly by a crank rod. Spreading elements are arranged between the sealing plate and the counter element tending to urge these members apart and the crank rod mechanism includes a slide member which is arranged to move within a guide slot in the sealing plate and to also engage a circumferential edge of the counter element so that during closing movement of the sealing plate by engagement of the slide member in the guide slot, the slide member may also extend to engage the circumferential edge of the counter element to rotate the counter element relative to the sealing plate in order to place the spreading elements in position to apply a sealing force between the sealing plate and counter element.

Abstract: The plate valve has a housing forming an inlet spigot and an outlet spigot. A movable valve member provided with a closure plate and an orifice plate is movable radially of the spigots via servo-pistons which are rigidly connected to the valve member. The pistons are guided in cylinders disposed diametrically opposite one another on the spigots. The cylinders may be integrally formed with the plate valve housing or may be separably formed as cylinder heads.

Abstract: A gate valve is disclosed having a casing with inlet and outlet apertures one of which has a valve seat. An actuator reciprocal transversely of the apertures is provided having two oppositely disposed faces. At least one plate member which serves as a valve head flanks at least one of the faces for cooperation with said valve seat. And rectangular-shaped rotative means are positioned between the actuator member and the plate member for moving the plate member from an open to a closed/latched position as the actuator member is moved.

Abstract: A gate valve having an expandable valve closure apparatus which is capable of expanding to seal two oppositely located parts in its valve housing. The expandable valve closure apparatus if pivotally mounted for movement on the end of a swing arm member to permit the expandable valve closure apparatus to be moved from its operative position in the vicinity of the ports in the valve housing to its inoperative or stowed position within the valve housing. Expansion of the expandable valve closure apparatus is accomplished by compressed air that is fed into a bellows that forms part of the expandable valve closure apparatus. Contraction of the expandable valve closure apparatus is accomplished by permitting the compressed air to be released from within the bellows and by springs which form part of the expandable valve closure apparatus. Air pressure is also utilized to move the expandable valve closure apparatus from its operative to its inoperative position and from its inoperative to the operative position.

Abstract: A seal assembly is disclosed in connection with a valve, preferably a sliding gate valve. The seal assembly includes a retaining ring having a surface contour complementary to that on a resilient, replaceable seal element, in order to positively hold the seal in position during use. The ring also includes a threaded portion that may be received in a threaded section either in the valve body or in a separate valve seat collar secured within the valve body. In one embodiment, the seal includes an annular metallic component having an annular groove, into which a resilient component is secured.

Abstract: A valve structure in which a valve member moves into and out of contact with first and second valve seating areas, the valve member contacting the seating areas with different forces. The movable valve member is comprised of block members coupled together so that a change in their relative longitudinal positions produces a corresponding change in their relative transverse positions. A stem member moves the block members to spaced longitudinal positions and produces different longitudinal separating forces between the block member in these positions thereby to urge one of the block members in a transverse direction with different forces against the valve seating areas. The application of forces directly through block members and indirectly through springs is employed to provide different valve seating forces. Block members for valve port blocking and valve port opening are utilized. A shock absorbing structure incorporating a movable spring holder is also utilized.

Abstract: A high vacuum valve comprises a casing having a valve inlet port and a va outlet port connected to the inlet port with a valve seat defined between the inlet and outlet ports. The casing also defines a valve movement passageway and a valve member is movable in the housing along the passageway between a position in which it is aligned with the valve seat for closing the valve and one in which it is out of alignment with the seat to open the valve. The valve member includes two separate relatively movable plate parts both of which move along the passageway together and one of which is movable when the valve member is aligned with the valve seat so as to move into engagement with the seat.

Abstract: A gate valve (10) has an expanding gate assembly (34) mounted in the valve chamber (14) for movement between open and closed positions. The gate assembly (34) includes a gate (44) connected to a valve stem (28) and a segment (52) is carried by the gate (44). The gate (44) and segment (52) each have wedging surfaces (46 and 54) which permit a wedging action to provide lateral expansion therebetween at the open and closed positions. A rocker arm (80) is pivotally mounted to a side (49) of the gate (44). The rocker arm (80) has a slot (102) with a bearing block (104) slidably received therein. A bearing pin (110) extends from a side (57) of the segment (52) and is journaled in the bearing block (104). A seat skirt (60) is contained within the valve chamber (14) and engages the rocker arm (80) so as to control the ability of the rocker arm (80) to pivot about the gate (44) thereby allowing the gate (44) and segment (52) to expand from each other at a preselected position in the travel of the gate assembly (34).

Abstract: A pendulum gate valve with a pressure tight housing and inlet and outlet openings arranged on opposite sides of the housing. The drive rod for the pendulum frame is guided throughout its total path by a joint connected to the pendulum frame which can swivel about the shaft of the pendulum frame but can in addition also move independently of the swiveling motion of the pendulum frame. A guide mechanism is provided for the further movement of the joint outside the swiveling range, which forces the joint onto a path that runs substantially parallel to the drive rod. The guide mechanism consists of a thrust rod forming part of the pressing device which urges the gate valve plate against the sealing bearing surface and which is connected to the drive rod. The thrust rod is mounted in a longitudinally movable manner in the pendulum frame and runs parallel to the drive rod in the closed position of the gate valve plate.

Abstract: A valve seat structure for an expanding type gate valve (20). A valve seat (64) is received in each annular seat recess (62) formed around the upstream and downstream flow passages (24, 26) and opening to the valve chamber (22) wherein a gate assembly (32) is movable between open and closed positions. An annular face seal (82) is mounted within an annular groove (70) in the front seat face (66) of each valve seat (64). A substantial portion of the bottom (76) of the annular groove (70) comprises a frusto-conical bottom portion (80) which forms a wedging surface with a cone angle in the range of approximately 30.degree. to 60.degree. and disposed substantially coaxial with the groove sides and the flow passages. The rear seal face (86) of the face seal (82) has a frusto-conical rear portion (94) that conforms to the frusto-conical bottom portion (80). The annular groove (70) is wider than the thickness of the face seal (82 ) so that the face seal loosely fits within the annular groove.

Abstract: In an expanding gate valve, tangential pins (70) are received loosely in peripheral grooves (62) of floating valve seats (26) to prevent the seats from moving inwardly far enough to drag against a gate mechanism (32) which is collapsed for movement between open and closed positions of the valve. Alternative arrangements provide retainer rings (122, 130) which engage shoulders (128) of the seats to limit their inward floating movement.

Abstract: A new and improved gate valve suitable for use with high pressure, high temperature corrosive fluids such as those developed in coal gasification processes, uranium enrichment and the like comprises a valve body having a flow passage with a pair of opposed annular valve seats and a gate assembly mounted for movement transversely of the flow passage between a valve seat confronting position and an open position displaced transversely outwardly of the passage. The gate assembly includes a pair of flat spring flexure elements which support a pair of valve discs for movement toward and away from the valve seats when the assembly is in the valve seat confronting position. These flexure elements normally bias the valve discs out of engagement with the valve seats. The discs are interconnected by an upwardly bowed flexure element which is retained between upper and lower holding members connected to the transversely extending stem of the gate valve.

Abstract: The gate assembly (24) of an expanding gate valve has projecting pins (74, 76, 78) which engage guide surfaces (54, 66) of guide rails (52, 64) in order to maintain the gate assembly in a collapsed condition between its open and closed positions. At the fully open and fully closed positions, the pins register with gaps (56, 58, 60, 68, 70) in the guide surfaces to permit expansion of the gate assembly against a pair of valve seats (20, 22).

Abstract: An expanding gate valve having seats (74) which are mechanically secured in place. The valve body has seat pockets which include undercut grooves (78) intersected by a cylindrical body cavity (24) to form a pair of openings (80) to each groove. Each valve seat has a pair of lugs (90) which may be fitted through the openings and into the undercut groove. Subsequent rotation of the seat locks the lugs in the groove to secure the seat in place in its seat pocket. Each seat is able to pivot about an axis extending between the lugs in order to compensate for irregularities in the contact surfaces of the gate or seat.

Abstract: A vacuum-tight closure assembly includes a valve seat; a spreadable valve plate movable into a closed position for assuming a spreaded state in which it sealingly engages the valve seat; and a guide arrangement for a centered guiding of the valve plate during its motion into the closed position. The guide arrangement includes guide faces located in the vicinity of and stationarily with respect to the valve seat and counterguide faces located on and movable with the valve plate. The guide faces cooperate with the counterguide faces during the motion of the valve plate towards the closed position.

Abstract: An expanding gate valve having a pair of seat spacers (70) which hold apart a pair of floating valve seats (32) to prevent them from binding against a gate mechanism (40) which is collapsed for movement between open and closed positions. The spacers (70) are cylindrical segments which fit in the valve chamber of a gate valve having a cylindrical body cavity (20).

Abstract: An improved spring plate (52) for insuring timely cooperation between the gate member (36) and segment member (38) of a linearly reciprocating gate assembly (34) which is expansible to seal the opposed seats of a gate valve. The two members have two pairs of interfacing wedge surfaces which should be in full contact when the assembly is traveling between the extremities of its stroke. Only at the ends of such stroke, as determined by a stop which halts movement of the segment member, should wedging and transverse expansion take place.The spring plate (52) has the general shape of an inverted "T" plus a pair of curved spring fingers (60, 62) extending from the free top end of the upright leg (54) toward the opposite ends of the assembly. The base legs (56,58) of the inverted "T" pass under the two pins (72, 74) in the gate member, which are located at equal distances from the mid-length of the gate member.

Abstract: A gate valve structure has a one-piece cage (76) in the form of an open ended sleeve which fits in the valve chamber of the body. The cage includes a pair of openings (82) which are aligned with the inlet and outlet flow passages in the body. Seats (60, 62) are mounted within the openings of the cage and have outwardly extending lugs (66) which are received within slots (88) in flanges (86) about openings (82) in the cage. The flanges (86) limit the inward movement of the seats toward the gate assembly and maintain a predetermined minimum spacing between the seats to minimize binding of the seats against the gate. The seats are easily inserted within the openings of the cage after the cage is fitted within the valve body.

Abstract: There is disclosed a valve having an expanded gate comprising a pair of ported segments each having "V"-shaped, oppositely facing inner surfaces which are yieldably urged into conformity with one another by a pair of leaf springs. Each leaf spring is disposed about a pin on one side of a first segment intermediate its ends, and has one of its ends anchored to the first segment, and the other end anchored to the second segment.

Abstract: A gate valve structure having a pair of opposed spacer carriers (72,74) fitting within the valve chamber in abutting relation to each other and spacing the floating upstream and downstream seats (60, 62) from each other a predetermined minimum distance. Each carrier (72, 74) has an annular base (76) adjacent one of the flow passages and a pair of spacers or guides (78, 80) secured to the base and extending from the base (76) in a direction axially of the flow passage. The spacers (78, 80) on opposed carriers are in abutting relation to each other and form a smooth continuation. An expanding gate assembly (28) fits between the spacers and moves between open and closed positions relative to the flow passages.

Abstract: An improved gate valve of the expanding type wherein a gate and segment assembly having cooperative wedge surfaces are moved linearly between a pair of valve seats to block the flow therebetween in one position and open the flow in another, the fluid flowing through aligned ports in the gate and segment in such open position. The improvement lies in substituting for prior art springs a guide rail (28, 28') fixed to the valve housing or body and extending parallel to the stroke of the movable members, together with a rocker arm (54) pivotally mounted on one member and having a slot (66) receiving a pin (58) out of the other. A pair of lobes (64) extend from the opposed ends of the rocker arm (54) and contact the guide member. When the gate and segment assembly are at any position between the ends of its stroke, the rocker arm keeps both pairs of wedge surfaces tightly in contact, preventing any expansion.

Abstract: A gate valve having a gate assembly of the expanding type employing a gate element (34) and segment (36) with adjacent wedge surfaces to expand the gate mechanism in both open and closed positons. Opposed floating seat skirts (68) having integral seat assemblies (52, 54) are positioned on opposite sides of the expanding gate valve and have facing slots (76) therein to receive spacer plates (82) therein which maintain a predetermined spacing between the skirts to minimize any binding of the skirts against the gate assembly and to provide a predetermined minimum clearance between the skirts at all times.

Abstract: A gate valve for use with vacuum equipment is provided in which a gate assembly is opened and closed by a fluid operated device, such as a pneumatic cylinder. The gate assembly is enclosed in a valve housing. The valve housing has aligned openings therein, and the gate assembly is moved reciprocally between the walls and parallel to the planes of the aligned openings therein, to an open position and to a closed position with respect to the openings. The gate assembly comprises two gates which are intercoupled by a bellows, the bellows defining a hermetically sealed pressure vessel with the gates. The gate assembly is coupled to a piston in the pneumatic cylinder by a piston rod. The gate assembly is moved to its closed position when pressurized fluid is introduced to one end of the pneumatic cylinder; and the gate assembly is moved to its open position when pressurized fluid is introduced to the other end of the cylinder.

Abstract: A valve having a body with a valve seat and valve element and actuating means for moving the valve element toward and away from the valve seat with stop means in the body for stopping the movement of the valve element when the element is positioned against the valve seat. Fluid-actuated seal means are provided for sealing between the valve seat and the valve element and fluid-actuation means including a piston and cylinder which are in fluid communication with the seal means for actuation of the seal means. The fluid-actuation means are connected to the valve-actuating means whereby the seal means are pressurized and relieved by movement of the valve-actuating means.

Abstract: This invention relates to an improvement in a conventional double-disc gate valve having a vertically movable gate assembly including a wedge, spreaders slidably engaged therewtih, a valve disc carried by the spreaders. When the gate assembly is lowered to a selected point in the valve casing, the valve discs are moved transversely outward to close inlet and outlet ports in the casing. The valve includes hold-down means for guiding the disc-and-spreader assemblies as they are moved transversely outward and inward. If such valves are operated at relatively high differential pressures, they sometimes jam during opening. Such jamming has been a problem for many years in gate valves used in gaseous diffusion plants for the separtion of uranium isotopes.The invention is based on the finding that the above-mentioned jamming results when the outlet disc tilts about its horizontal axis in a certain way during opening of the valve.

Abstract: This invention relates to a double-disc gate valve which is compact, comparatively simple to construct, and capable of maintaining high closing pressures on the valve discs with low frictional forces. The valve casing includes axially aligned ports. Mounted in the casing is a sealed chamber which is pivotable transversely of the axis of the ports. The chamber contains the levers for moving the valve discs axially, and an actuator for the levers. When an external drive means pivots the chamber to a position where the discs are between the ports and axially aligned therewith, the actuator for the levers is energized to move the discs into sealing engagement with the ports.

Abstract: A gate value having a sealing plate carried by a moveable element which through the coaction of a series of balls presses the sealing plate into a flow preventing position.