Abstract: In order to prevent contamination of a fluid source and to ensure drainage of a sill cock or the like, a detachable check valve back flow preventer for installation between a fluid inlet line and a fluid outlet line is provided. A housing with means for fastening the device to a fluid inlet line at one end of the housing and for connecting a fluid outlet line at the other end of the housing is provided. The housing has a central cavity within the housing. An inlet line drain valve is located within the housing between the central cavity and the fluid inlet line to provide for the drainage of fluid from the fluid inlet line to the fluid outlet line end of the housing when the fluid outlet line is not connected to the back flow preventer. A second valve is located within the housing between the central cavity and the fluid inlet line to control flow of fluids between the fluid inlet line and the central cavity.

Abstract: A self-draining hose connection vacuum breaker and backflow preventer having a flexible annular diaphragm and a coacting seat disc movable relative thereto which, together, function to prevent backflow through the device and with the annular diaphragm coacting with atmospheric vents to provide a vacuum break and fluid drain. A movable piston has two different positions, dependent upon whether or not a hose is connected to the device, with the piston mounting the seat disc for movement therewith and relative thereto whereby the seat disc and annular diaphragm coact to prevent backflow when a hose is attached to the device, but the seat disc is positioned to permit flow through a central opening of the annular diaphragm when a hose is removed from the device to prevent trapped water in a source valve, such as a faucet or the like, which could result in either pipe and/or valve rupture resulting from freezing or retention of stagnant water which could result in bacterial growth.

Abstract: A thermal element having a tubular casing with an open end, a volume of heat-responsive, expandable wax positioned in said casing at a distance from the open end thereof, a spherical resilient seal member compressively positioned in the casing adjacent said wax, a motion-transmitting pin extended between the seal member and the open end of the casing and having a relatively soft washer affixed thereto for engagement against the seal member and with at least one peripheral notch in the washer permitting flow of liquid thereacross.

Abstract: A fire hydrant having a generally elbow-shaped hydrant shoe with an improved interior bowl configuration and an improved hydrant valve for minimizing head or flow loss of the fire hydrant between the inlet opening of the shoe and the outlet nozzle positioned on the upper portion of the hydrant barrel. The interior bowl of the shoe, adjacent its inlet, is provided with a diverging transitional surface of rotation having a generally part frusto conical shape and, adjacent its outlet, is provided with a converging transitional surface of rotation having a generally part frusto conical shape, the transitional surfaces of rotation merging with the shoe's part spherical chamber.

Abstract: A fire hydrant having a generally elbow-shaped hydrant shoe with an improved interior bowl configuration and an improved hydrant valve for minimizing head or flow loss of the fire hydrant between the inlet opening of the shoe and the outlet nozzle positioned on the upper portion of the hydrant barrel. The interior bowl of the shoe, adjacent its inlet, is provided with a diverging transitional surface of rotation having a generally part frusto conical shape and, adjacent its outlet, is provided with a converging transitional surface of rotation having a generally part frusto conical shape, the transitional surfaces of rotation merging with the shoe's part spherical chamber.

Abstract: A fire hydrant comprising a barrel member having an open upper end with an apertured type closure member detachably secured thereto, the apertured top closure member including a generally flat plate portion and a downwardly extending annular portion. The top closure member is secured to the barrel member by bolt means arcuately spaced therearound and the closure member together with the operating nut define a lubricant reservoir for lubricating the hydrant valve stem and cooperating operating nut. A hold-down nut received in the apertured top closure member holds the operating nut relative to the closure member for rotation and an inverted dish-shaped weather cap is threadedly received on the hold-down nut to protect the bolt means holding the closure member on the barrel as well as to protect the access means for the lubricant reservoir.

Abstract: An improved relief valve of the type responsive to a predetermined thermal and/or pressure condition. The valve includes a valve body having an inlet, an outlet, an internal passage interconnecting the two, a valve seat about the passage and an opening coaxial with the valve seat, a poppet valve within the body, including a stem extending towards the opening and having a pressure responsive surface directed toward the inlet side of the valve seat, a closure disposed within the opening and having a central aperture slidably and sealingly receiving the stem, the closure being formed of a thin, relatively ductile material and having an outwardly extending lip frictionally captured by the body about the opening and sealingly engaging the body thereabout, the closure further including an annular convex ridge inwardly of the lip and within the body and a central pedestal directed oppositely of the ridge.

Abstract: An assembly for closing a side opening in a pipe and including a fitting attached to the pipe and having a tubular portion aligned with the opening and a completion plug inserted into the tubular portion to seal the opening from the exterior of the pipe. The completion plug is provided with circumferentially spaced lugs lying in a plane normal to the axis of the plug, the lugs being arranged to fit into a groove in the tubular portion of the fitting, there being spaced arcuate cutouts in the tubular portion whereby the arrangement is a bayonet-type of fastening. Stop means are provided to limit rotation of the plug in a closing direction and further stop means are provided for preventing inadvertent removal of the plug from the fitting. A third stop means is provided for stopping the plug when being rotated to a position for removal, the third stop means aligning the lugs of the plug with the cutouts in the fitting so that the plug can be retracted from the fitting.

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.