A first diaphragm and a second diaphragm are disposed between a valve element and a body, a diaphragm chamber is formed between the first diaphragm and the second diaphragm, the first diaphragm separates a valve chamber from the diaphragm chamber, and the second diaphragm separates the diaphragm chamber from a back pressure chamber. The diaphragm chamber communicates with an output port, the valve chamber and the back pressure chamber communicate with an input port. A difference between an effective pressure receiving area of the first diaphragm and an effective pressure receiving area of the second diaphragm is equivalent to a passage area in a valve seat.

A first diaphragm and a second diaphragm are disposed between a valve element and a body, a diaphragm chamber is formed between the first diaphragm and the second diaphragm, the first diaphragm separates a valve chamber from the diaphragm chamber, and the second diaphragm separates the diaphragm chamber from a back pressure chamber. The diaphragm chamber communicates with an output port, the valve chamber and the back pressure chamber communicate with an input port. A difference between an effective pressure receiving area of the first diaphragm and an effective pressure receiving area of the second diaphragm is equivalent to a passage area in a valve seat.

A pressure regulator includes a regulated fluid volume, at least one vent passage and fluid supply passage, a dampening piston bore and a regulated fluid volume outlet passage, a regulated fluid pressure piston having a first surface side exposed to the regulated fluid volume, and a second surface side exposed outwardly of the body, an external biasing member contactable with the piston and providing a force on the piston inwardly of the body, a gate connected to the piston, a dampening piston disposed in the dampening piston bore, the dampening piston disposed between a dampening and regulated fluid volumes and including a recess including a band therein having at least one gap therethrough, the gap in the band forming a passage between the dampening piston and the piston bore communicable with a volume exterior to the region between the dampening piston and the piston bore.

A flow control valve includes a housing defining a cavity therein. The housing has an input port for receiving a gas from a gas supply, and an output port for delivering the gas to a gas cylinder. The cavity defines a staging area fluidly connected to the input port, a delivery area fluidly connected to the output port, and a pressurization area fluidly connected to a feedback sensing port. The feedback sensing port is configured to receive pressurized fluid that is pressurized to a pressure level representative of a pressure level of gas delivered to the gas cylinder. The flow control valve includes a piston slidably positioned in a channel extending between the pressurization area and the delivery area. The position of the piston changes a rate of flow of gas through the flow control valve. The piston position moves in response to a pressure at the feedback sensing port.

A pressure-limiting valve includes a housing having a piston, a pressure-limiting adjusting spring, at least one inlet and at least one outlet. The piston can assume an open position in which the inlet and the outlet are connected to each other, and at least one closed position in which the inlet and the outlet are separated from each other. The piston has a first piston ring with a sealing surface and a second piston ring. In the closed position, the sealing surface is drawn against a housing projection in a sealing manner by a pneumatic force which acts on the second piston ring and is directed against the force of the pressure-limiting adjusting spring. A pneumatic passage in the piston which implements a safety valve function can be sealed by a spring-loaded safety valve body arranged on a side of the second piston ring that is opposite the outlet.

A pressure regulator includes a regulated fluid volume, at least one vent passage and fluid supply passage, a dampening piston bore and a regulated fluid volume outlet passage, a regulated fluid pressure piston having a first surface side exposed to the regulated fluid volume, and a second surface side exposed outwardly of the body, an external biasing member contactable with the piston and providing a force on the piston inwardly of the body, a gate connected to the piston, a dampening piston disposed in the dampening piston bore, the dampening piston disposed between a dampening and regulated fluid volumes and including a recess including a band therein having at least one gap therethrough, the gap in the band forming a passage between the dampening piston and the piston bore communicable with a volume exterior to the region between the dampening piston and the piston bore.

A balanced farm tap regulator includes a valve housing having a fluid inlet and a fluid outlet connected by a fluid passageway. A valve seat is disposed in the fluid passageway. A removable balanced plug assembly includes a valve stem having a stem balanced fluid passage, a disk that cooperates with a valve seat to control fluid flow, and a stem guide that is removably attached to the valve housing. The disk includes a disk balanced fluid passage that is fluidly connected with the stem balanced fluid passage. The stem guide is removably attached to the valve housing, the stem guide including an inwardly extending guide flange and an externally extending guide flange. The inwardly extending guide flange cooperates with the valve stem to form a balance chamber, and the stem balanced fluid passage is fluidly connected to the balance chamber and to the disk balanced fluid passage.

A pressure-limiting valve includes a housing having a piston, a pressure-limiting adjusting spring, at least one inlet and at least one outlet. The piston can assume an open position in which the inlet and the outlet are connected to each other, and at least one closed position in which the inlet and the outlet are separated from each other. The piston has a first piston ring with a sealing surface and a second piston ring. In the closed position, the sealing surface is drawn against a housing projection in a sealing manner by a pneumatic force which acts on the second piston ring and is directed against the force of the pressure-limiting adjusting spring. A pneumatic passage in the piston which implements a safety valve function can be sealed by a spring-loaded safety valve body arranged on a side of the second piston ring that is opposite the outlet.

A flow control valve includes a housing defining a cavity therein. The housing has an input port for receiving a gas from a gas supply, and an output port for delivering the gas to a gas cylinder. The cavity defines a staging area fluidly connected to the input port, a delivery area fluidly connected to the output port, and a pressurization area fluidly connected to a feedback sensing port. The feedback sensing port is configured to receive pressurized fluid that is pressurized to a pressure level representative of a pressure level of gas delivered to the gas cylinder. The flow control valve includes a piston slidably positioned in a channel extending between the pressurization area and the delivery area. The position of the piston changes a rate of flow of gas through the flow control valve. The piston position moves in response to a pressure at the feedback sensing port.

A flow control valve includes a housing defining a cavity therein. The housing has an input port for receiving a gas from a gas supply, and an output port for delivering the gas to a gas cylinder. The cavity defines a staging area fluidly connected to the input port, a delivery area fluidly connected to the output port, and a pressurization area fluidly connected to a feedback sensing port. The feedback sensing port is configured to receive pressurized fluid that is pressurized to a pressure level representative of a pressure level of gas delivered to the gas cylinder. The flow control valve includes a piston slidably positioned in a channel extending between the pressurization area and the delivery area. The position of the piston changes a rate of flow of gas through the flow control valve. The piston position moves in response to a pressure at the feedback sensing port.