Disclosed is an air mix valve including: a wall having at least three openings; and at least one airflow-regulating device. The airflow-regulating device includes: at least two shutters placed in the internal volume of the valve, at least one aerodynamic shutter of which is arranged with respect to one of the openings so as to be able to receive an airflow passing through this opening, and a linking mechanism between at least two shutters. Each of the shutters is arranged and guided so as to be able to be caused to move with respect to the wall. At least one airflow-regulating device, named aero-controlled regulation device, is mounted to be freely movable under the effect of aerodynamic energy from airflows passing through the openings.

An apparatus to allow or stop an air flow into an enclosed environment or piping system comprises (a) a housing, (b) a first valve seat, (c) a first sealing member, (d) a second valve seat, (e) a second sealing member, (f) at least one locking mechanism configured to limit a movement of the first sealing member and/or the second sealing member; wherein the first sealing member moves away from the first valve seat when the second pressure is greater than the first pressure in a predetermined pressure difference; wherein the second sealing member moves away from the first valve seat when the third pressure is greater than the second pressure in a predetermined pressure difference; wherein the first pressure communicates with a system pressure in the piping system; and wherein the third pressure communicates with an ambient air pressure.

A dishwasher includes a water jacket. The water jacket includes a water discharge path configured to discharge wash water to an outside of the dishwasher, a chamber in fluid communication with an upper end of the water discharge path, a check valve disposed inside the chamber, and a hinge disposed in the chamber and connected to the check valve. The check valve includes a floating portion with an empty inside. The specific gravity of the floating is smaller than that of water.

A dishwasher includes a water jacket. The water jacket includes a water discharge path configured to discharge wash water to an outside of the dishwasher, a chamber in fluid communication with an upper end of the water discharge path, a check valve disposed inside the chamber, and a hinge disposed in the chamber and connected to the check valve. The check valve includes a floating portion with an empty inside. The specific gravity of the floating is smaller than that of water.

A flapper and seat assembly, and systems and methods utilizing such assembly, are disclosed. The flapper and seat assembly includes a tubular metallic seat having a bore therethrough. The tubular metallic seat is one solid unit. The flapper and seat assembly further includes a hinge coupled to the tubular metallic seat and a flapper. The flapper is pivotally mounted to the hinge such that it is rotatable between an open position and a closed position. The flapper and seat assembly also includes a secondary sealing element located between the flapper and the tubular metallic seat. The secondary sealing element is one of an undulating or curved lip seal. The flapper and seat assembly further includes a seal that is formed between a sealing surface of the flapper and a sealing surface of the tubular metallic seat. The seal comprises an angle measured from a plane perpendicular to the centerline of the flapper and seat assembly.

A butterfly valve includes a valve body and valve clack in the valve body. The valve body is installed with at least one sprinkler connected to an inlet valve outside the valve body for purging the inner surface of butterfly valve in the middle of the valve clack is a horizontal drainage tray, one end of which is closed and the other is water outlet, and the valve clack is equipped with at least one drain hole connected to the drainage tray; the sprinkler is above the drainage tray. This invention can be filled with corresponding media for online cleaning, sterilization and drying of non-sterile areas of a butterfly valve group after conveying the powder to realize repeated butt-joints.

A check valve can include a valve body defining a valve bore, the valve body comprising an annular body and a cross member secured to and extending in a radial direction across the valve bore from the annular body on one side of the valve body to the annular body on an opposite side of the valve body, the valve bore at the cross member divided into more than one portion by the cross member; a position block extending from the cross member; a pair of valve members, each valve member of the pair of valve members positioned within the valve body and configured to rotate between open and closed positions; and a pivot pin positioned within the valve body and extending through the position block and each valve member of the pair of valve members, the pivot pin being supported only by the position block.

Embodiments relate to a check valve and methods of making a check valve that include a valve body having an inlet end, an outlet end, a flow bore that extends between the inlet and outlet ends, a cavity which intersects the flow bore, and an opening which is connected to the cavity. In certain embodiments, the check valve further includes a cap removably secured in the opening, a seat cartridge disposed in the cavity, wherein the seat cartridge comprises a chamber with a flow bore, a retainer ring positioned in the valve body between the cap and the seat cartridge, a pivot pin retainer seal provided between the retainer ring and the valve body, wherein the pivot pin retainer seal comprises one or more protrusions extending outwardly in a radial direction from the retainer ring to seal on the valve body, and a flapper pivotally connected to the retainer ring, wherein the flapper is pivotable through the chamber between a closed position in which the flapper is positioned against a shoulder in the seat cartridge and an open position in which the flapper is displaced from the shoulder.

Embodiments relate to a check valve and methods of making a check valve that include a valve body having an inlet end, an outlet end, a flow bore that extends between the inlet and outlet ends, a cavity which intersects the flow bore, and an opening which is connected to the cavity. In certain embodiments, the check valve further includes a cap removably secured in the opening, a seat cartridge disposed in the cavity, wherein the seat cartridge comprises a chamber with a flow bore, a retainer ring positioned in the valve body between the cap and the seat cartridge, a pivot pin retainer seal provided between the retainer ring and the valve body, wherein the pivot pin retainer seal comprises one or more protrusions extending outwardly in a radial direction from the retainer ring to seal on the valve body, and a flapper pivotally connected to the retainer ring, wherein the flapper is pivotable through the chamber between a closed position in which the flapper is positioned against a shoulder in the seat cartridge and an open position in which the flapper is displaced from the shoulder.

A flapper check valve employed to prevent flow up the work string while allowing flow down the work string and into the well is disclosed. The check valve is activated by a compression spring, which then acts on a ball which will further act on a cam profile attached to the back of a flapper. The apparatus causes the flapper to default to the closed position when the flow is stopped, regardless of the position of the valve, even when gravity is acting against the flapper. The compression spring also allows for an apparatus which possesses lower operating stresses on the spring.