Provided is a valve with which a seal member is not damaged when pressure accumulated near the seal member is released. This valve includes a valve box having a valve chamber, a valve seat provided in the valve chamber and having a seat surface, a stem including, at a tip end thereof, a valve element configured to abut against and move away from the seat surface due to an operation of an actuator, a seal space provided with a seal member configured to prevent a fluid from leaking, a seal opening space formed outside the seal space, and a seal pressing member configured to press and fix the seal member to a valve chamber side. The valve box is formed with a leak hole through which the seal space and the outside of the valve box communicate.

Provided is a valve with which a seal member is not damaged when pressure accumulated near the seal member is released. This valve includes a valve box having a valve chamber, a valve seat provided in the valve chamber and having a seat surface, a stem including, at a tip end thereof, a valve element configured to abut against and move away from the seat surface due to an operation of an actuator, a seal space provided with a seal member configured to prevent a fluid from leaking, a seal opening space formed outside the seal space, and a seal pressing member configured to press and fix the seal member to a valve chamber side. The valve box is formed with a leak hole through which the seal space and the outside of the valve box communicate.

A pressure-tight stein cylinder seal and a self-energizing stein shoulder seal matching the stein cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stein cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stein 02 cylinder and another radial compression force 2f of their soft ring 06 on the stein 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stein corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

A pressure-tight stein cylinder seal and a self-energizing stein shoulder seal matching the stein cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stein cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stein 02 cylinder and another radial compression force 2f of their soft ring 06 on the stein 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stein corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

A pressure-tight stem cylinder seal and a self-energizing stem shoulder seal matching the stem cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stem cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stem 02 cylinder and another radial compression force 2f of their soft ring 06 on the stem 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stem corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

A valve device includes a housing, a valve, a partition wall, and a seal member. The partition wall is fit into the housing. The housing includes a first cylindrical inner wall, a second cylindrical inner wall, and a third inner wall. The second cylindrical inner wall is tapered from the third inner wall to the first cylindrical inner wall and the third inner wall defines a housing through hole. The partition wall defines a partition wall through hole that extends in the radial direction and that overlaps with both the first cylindrical inner wall and the second cylindrical inner wall in the radial direction. An annular space that is in communication with both the partition wall through hole and the housing through hole is defined between the second cylindrical inner wall and the outer wall of the partition wall.

A valve assembly includes a body having spaced apart ports defining a flow passageway therebetween and a top surface. A valve is disposed in the flow passageway. A bonnet is coupled to the top surface of the body. A rising stem is supported by the bonnet and is operably coupled to the valve. A cap includes a bottom sealingly coupled to at least one of the body or the bonnet and an opening. The cap is disposed over the bonnet with the stem extending through the opening.

A valve assembly includes a body having spaced apart ports defining a flow passageway therebetween and a top surface. A valve is disposed in the flow passageway. A bonnet is coupled to the top surface of the body. A rising stem is supported by the bonnet and is operably coupled to the valve. A cap includes a bottom sealingly coupled to at least one of the body or the bonnet and an opening. The cap is disposed over the bonnet with the stem extending through the opening.

A pressure-tight stem cylinder seal and a self-energizing stem shoulder seal matching the stem cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stem cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stem 02 cylinder and another radial compression force 2f of their soft ring 06 on the stem 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stem corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.

A pressure-tight stem cylinder seal and a self-energizing stem shoulder seal matching the stem cylinder seal that both use an equilaterally triangular soft ring as their sealing element, wherein their designing rules are first, by means of wedging function of a hard gland coaxial with the stem cylinder, to convert their original axial tightening force 2f respectively into a radial compression force 4f/√3 of their soft ring 04 on the stem 02 cylinder and another radial compression force 2f of their soft ring 06 on the stem 02 shoulder and ensure that the two soft rings are so compressed from a great room to a small room as to be able to pass a pressure or stress exactly to each different direction, then to cut off their off-stem corners to give their cavities an opening or give each soft ring an axial compressing allowance, and last, by means of anti-extrusion metallic C-rings without axial resistance, to close each opening to provide a full support for the sealing deformation of their soft rings compressed in their cavities.