Abstract: A mount for a damper which is inserted between duct sections. An assembly of bent plate spring duct seal members forms a seal assembly mounted on each duct section at adjacent ends of the duct sections. The damper plate advances between the seal assemblies in sealing relation with the seal members. An enclosure surrounds the seal assemblies to form a chamber surrounding the seal assemblies. Air is blown into the chamber to prevent escape of contents of the duct sections at the damper plate. Access openings are provided in the enclosure. Adjoining edges of the spring seal members are bridged by angle-shaped bridge members.

Abstract: A housing, connectable to a pipe, has therein an opening, a chamber, a stationary sealing seat, and a movable sealing seat displaceable toward and away from the stationary sealing seat. A slide plate is movable from an open position, exterior of the housing, through the opening to a closed position between the sealing seats to block the pipe. A closing element closes the opening and seals the chamber when the slide plate is in the open position.

Abstract: A gate valve seat ring retainer particularly for a non-ported gate valve comprising an annular seat ring mountable in a seat pocket around the flow passageway in a gate valve body. A recess in the valve body opens into the flow passageway in a spaced relation to the seat pocket. An elongated retainer extending in the flow passageway has one end portion secured to the seat ring and the opposite end portion engaged in the recess to hold and retain the seat ring in place in the gate valve body.

Abstract: A gate valve having a replaceable one piece bore and chest liner enclosed within a pair of mirror image castings is disclosed. The gate is cast and enveloped within molded material to cooperate with the liner in a sealing relationship.

Abstract: A gate valve includes a pair of identically shaped tapered discs defining a tapered self-locking axially translatable gate wherein each disc has an annular hardened seating surface which engages the mating surfaces on the valve body adjacent the flow ports. Tongues on the sides of the discs ride in vertical grooves on the valve body as the gate travels between a raised open and a lowered closed position. The discs of the gate are provided with a slot transverse to the flow ports which captures a T-head on the stem assembly, the slot being positioned in the gate interior radially within the seating contact area to thereby reduce the overall height of the valve.

Abstract: A gate valve structure for use in mains carrying fluids, the gate valve structure being provided with a casing having a through-bore and a chamber communicating with the through-bore and in which a gate member reciprocates between closed and opened positions of the valve. The valve casing is split into two body members on a plane normal to the axis of the through-bore and one of the body members is arranged to contain all of the functional parts of the valve, including the valve seat, gate member, and actuating means for the gate member. By such an arrangement, the valve seat surrounding the through-bore in the one body member may be easily machined by conventional machining methods and the internal surfaces of both body members may be easily treated to make them non-corrosive.

Abstract: A packingless gate valve having a stepped through passage defined by respective half housings formed with passages of different diameter and respective bolt connector flanges disposed in face to face relation with spacer strips interposed between diametrically opposite flange face margins to define a laterally related gate passage, a compressible elastomeric liner sleeve fitted to the passage of greater diameter with its opposite ends protruding axially from the passage ends and the end opposed to the flange face defining the end of the smaller diameter passage formed to span the gate passage and provide a protruding lip sealingly engaging the last mentioned flange face in annular surrounding relation to the smaller diameter passage end, a gate having a leading knife edge slidingly mounted in the gate passage with the lead tip of the knife edge disposed to enter the line of seal and deform the lip into sealing engagement with the opposed face of the knife edge and gate in its reciprocal movement in the gate p

Abstract: A gate valve having a non-yielding body with a gate accommodating chamber with flat, downwardly converging end seating surfaces about portions of a flow passage communication with the chamber and downwardly convergent side seating surfaces, a wedge-shaped relatively soft resilient gate with downwardly convergent end sealing surfaces to establish tight sealing and wedging engagement with the end seating surfaces and downwardly convergent side surfaces to establish wedging engagement with the side seating surfaces, the angle of said end surfaces being less accute than the angle of said side surfaces whereby forces directed laterally inwardly and resolved axially in the gate by the side walls is greater than axial forces generated by the end surfaces when the gate is urged down in the body and whereby the end surfaces are urged and held in conforming seated and sealed engagement by the laterally directed and axially resolved forces, and operating means carried by the body and engaging the gate to selectively mov

Abstract: In a knife gate valve, an elastomer O-ring is held in an annular groove in a face of a valve seat by cotter pins having their eyes embedded in the O-ring and their shanks extending through the valve seat and clinched over. The eyes are adhered to the O-ring by vulcanization of the O-ring.

Abstract: A self-contained vacuum aspirator system is disclosed which comprises a container having a vacuum applied therein; a valve assembly secured to said container for selectively allowing the passage of fluid into said container; a curette in communication with an aperture in said valve assembly; and an air permeable collection means supported within said container by the aforementioned valve assembly in communication with an opening in said valve assembly for accumulating matter collected by said currette when the valve assembly is operating to establish communication between the aforementioned aperture and opening.