A valve body defines a work passage, a high-pressure channel fluidly connected to the work passage, a tank passage, and a cavity disposed between the high-pressure channel and the tank passage. The cavity fluidly connects the high-pressure channel and the tank passage. The cavity is defined at least in part by a first portion within which a relief valve threadedly engages, a second portion disposed adjacent to the high-pressure channel, and an annulus interposed between the first portion and the second portion. The annulus fluidly connects to the tank passage. A surface area of the relief valve exposed to the annulus is greater than a cross-sectional area of the high-pressure channel.

A rupture disc valve device as provided herein is configured to selectively release a pressurized material. In some embodiments, the rupture disc has a burst pressure rating less than a pressure of the pressurized material. The valve device selectively braces the rupture disc until release of the pressurized material is desired. To release the pressurized material, the valve device is configured to remove or adjust the bracing support to the rupture disc, allowing the pressurized material to burst the rupture disc.

A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

A flow control manifold apparatus includes a housing defining a first flow path from a flow input port to flow output port and a second flow path from a return inlet port to a return outlet port. A first flow regulating valve is placed inline the first flow path and an excess flow path fluidly couples the first flow path to the second flow path. An excess pressure valve is placed inline the excess flow path and is in a closed orientation when the first flow regulating valve is open so that all of the fluid exits through the flow output port. The excess pressure valve is then in a partially open orientation when the first flow regulating valve is partially closed so that a first portion of the fluid exits through the flow output port and a second portion of the fluid exits through the return outlet port.

A pressure relief valve system has a fluid outlet (1) from a pressure vessel; a flexible expansion piece (4) at an end of the fluid outlet remote from the pressure vessel; a primary pressure relief valve has a valve seat and a valve lid (7). The valve seat has a flange (5) mounted on the expansion piece and the valve lid forms a valve seal with the flange. A fluid off-take (13) is connected to the fluid outlet (1) and a secondary pressure relief valve (11) receives fluid from the fluid off-take. The secondary pressure relief valve has an outlet (12) coupled to a valve opening actuator (15), whereby passage of fluid through the secondary pressure relief valve (11) causes the opening actuator to operate to open the valve lid (7).

A pressure relief valve system has a fluid outlet (1) from a pressure vessel; a flexible expansion piece (4) at an end of the fluid outlet remote from the pressure vessel; a primary pressure relief valve has a valve seat and a valve lid (7). The valve seat has a flange (5) mounted on the expansion piece and the valve lid forms a valve seal with the flange. A fluid off-take (13) is connected to the fluid outlet (1) and a secondary pressure relief valve (11) receives fluid from the fluid off-take. The secondary pressure relief valve has an outlet (12) coupled to a valve opening actuator (15), whereby passage of fluid through the secondary pressure relief valve (11) causes the opening actuator to operate to open the valve lid (7).

A flow control valve including a main valve and a pilot valve for controlling a piston of the main valve. The pilot valve is controlled in part with relatively high pressure fluid ported from a high pressure port of a flow sensor and relatively low pressure fluid ported from a low pressure port of a flow sensor, and also controlled with a control fluid applied to a control plate acting on a compression spring to bias the pilot valve. The pressure in the control fluid is controlled by pressurizing a control fluid reservoir with a mechanism accessible from outside the valve and the piping in which the valve is installed. The flow sensor and the reservoir are preferably disposed within the flange of the valve.

A flow control valve including a main valve and a pilot valve for controlling a piston of the main valve. The pilot valve is controlled in part with relatively high pressure fluid ported from a high pressure port of a flow sensor and relatively low pressure fluid ported from a low pressure port of a flow sensor, and also controlled with a control fluid applied to a control plate acting on a compression spring to bias the pilot valve. The pressure in the control fluid is controlled by pressurizing a control fluid reservoir with a mechanism accessible from outside the valve and the piping in which the valve is installed. The flow sensor and the reservoir are preferably disposed within the flange of the valve.

An adjustable damping valve device for a vibration damper, includes a main stage valve which is controlled by a pre-stage valve which is functionally connected in series with the emergency operation valve. A pressure relief valve having the constructional form of a seat valve is arranged inside the emergency operation valve and is functionally connected in parallel with the emergency operation valve. A valve body of the pressure relief valve is formed by at least one annular valve disk.