A backflow prevention assembly includes a body forming two buckets, wherein flow passes through the body from an inlet to an outlet along an axis and consecutively through each of the buckets. A single zone test cover encloses a first of the buckets to form a single zone chamber. A dual zone test cover encloses a second of the buckets with a dual zone cartridge assembly therein. The dual zone test cover has two test cocks. The dual zone cartridge assembly includes a frame having a valve seat, wherein the frame includes a lumen providing fluid communication from a dual zone chamber upstream of the valve seat to a first of the two test cocks of the dual zone test cover, and wherein the second of the two test cocks of the dual zone test cover is in fluid communication with the dual zone chamber downstream of the valve seat.

A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing made of multiple-piece construction. One or more pieces of the housing are configured to have a plurality of stay rods attached thereto. The stay rods interconnect the fluid end assembly and a power end assembly.

A high pressure pump. The pump comprises a fluid end assembly supported on a power end assembly. The power end assembly is modular and held together by a first set of stay rods. The fluid end assembly comprises a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing made of multiple-piece construction. One or more pieces of the housing are configured to having a second set of stay rods attached thereto. The second set of stay rods interconnect the fluid end assembly and a power end assembly and a vertically offset from the first set of stay rods.

A damping valve having a damping valve body with at least one flow channel for damping medium. A valve rod is arranged in the flow channel. The valve rod cooperates with a valve disk and a valve seat surface. The valve rod carries a further valve disk that cooperates with a second valve seat surface. The first valve disk together with the first valve seat surface forms a first partial valve having a first permanently open pilot orifice cross section, and the second valve disk together with the second valve seat surface forms a second partial valve having a second pilot orifice cross section, and a shuttle valve is formed which opens one partial valve and closes the other partial valve depending on the flow direction.

Seat valve, with a valve body having a plurality of inlet channels, with a plurality of closing elements arranged movably in a longitudinal direction L, each inlet channel being assigned a closing element for opening and closing the inlet channel, with a closing spring assigned to each closing element. The closing spring applies a prestressing force to the respective closing element to close the inlet channel. Each closing element assigned a braking device which is arranged separately from the closing element and which gradually brakes an opening movement of the closing element when the inlet channel is opened, independently of the closing spring. The braking device having a stop body with a stop surface against which the closing element can be brought to bear after an opening movement when the inlet channel is opened, the stop body being arranged movably and/or yieldingly in the opening direction of the closing element.

There is provided a system separator having a backflow preventer including a housing enclosing a main flow conduit, a valve seat inside the housing on the main flow conduit, and a valve body movable relative to the valve seat to close off the main flow conduit together with the valve seat in a closed position and to release the main flow conduit in an open position. The valve body is alternately movable between the closed position and the open position by at least one of a pressure difference in the main flow conduit or a force of a spring element, and the main flow conduit is divided in the area of the valve body into at least one outer flow conduit and one inner flow conduit, and the valve body encloses the inner flow conduit and forms at least one valve-body valve seat on the inner flow conduit.

A pressure relief valve includes a valve body including a monitored pressure inlet leading to a monitored pressure region, a piston having a shear seal bore and a surface facing the monitored pressure region, a vent passage and a the shear seal assembly comprising a seal plate having a sealing surface thereon, and the shear seal assembly includes a sealing surface facing the seal plate and having a first annular area, and a first surface having an annular surface area at least twice as large as the first area of the sealing surface, the first surface facing away from the first area, and a biasing seal in contact with the first surface.

A valve assembly includes: a valve body, having an inner cavity; a first pipeline arranged on the valve body, having one end that communicates with the inner cavity and another end that is configured to be connected to an air pump; a second pipeline arranged on the valve body, having one end that communicates with the inner cavity and another end that is configured to be connected to a bubble spraying interface of a pool; and a third pipeline arranged on the valve body, having one end that communicates with the inner cavity and another end that is configured to be connected to an inflating interface of the pool. When the air pump is in an activated state, the second pipeline is in a communicating state and supplies air to the spray bubble interface, and the third pipeline is in a communicating state and supplies air to the inflating interface.

Seat valve, with a valve body having a plurality of inlet channels, with a plurality of closing elements arranged movably in a longitudinal direction L, each inlet channel being assigned a closing element for opening and closing the inlet channel, with a closing spring assigned to each closing element. The closing spring applies a prestressing force to the respective closing element to close the inlet channel. Each closing element assigned a braking device which is arranged separately from the closing element and which gradually brakes an opening movement of the closing element when the inlet channel is opened, independently of the closing spring. The braking device having a stop body with a stop surface against which the closing element can be brought to bear after an opening movement when the inlet channel is opened, the stop body being arranged movably and/or yieldingly in the opening direction of the closing element.

A dual chamber fuel tank protector valve has a transversely oriented divider defining a plurality of apertures for fluid flow between a first port and a second port. Each chamber has a seal disk therein. The first seal disk is normally biased to an open position by a first biasing member. The second seal disk is normally biased to a closed position by a second biasing member having a preselected biasing force set to a preselected pressure differential that allows movement to its open position before the first seal disk moves to its closed position. When the first seal disk and the second seal disk move to their respective closed positions, the direction of movement is toward one another.