A flow arrangement for a pressure relief valve assembly can include a bypass flow path extending from a pressure source to a dome of a relief valve. The bypass flow path can include a valve that is configured to open and close the bypass flow path based on pressure at the pressure source or the dome, or a pressure difference between the pressure source and the dome.

A flow arrangement for a pressure relief valve assembly can include a bypass flow path extending from a pressure source to a dome of a relief valve. The bypass flow path can include a valve that is configured to open and close the bypass flow path based on pressure at the pressure source or the dome, or a pressure difference between the pressure source and the dome.

A pressure compensation device with an accumulator group for controlled pressure drilling includes an electrical flat valve, a check valve, an accumulator group, a flanged pup joint and a support base. The electrical flat valve is connected to the check valve and is mounted on a top surface of the support base. The accumulator group mounted on the whole support base is a pre-storage pressure compensation device for controlled pressure drilling, and is located at a downstream position of the check valve. The liquid inlet end of the accumulator group is connected to the check valve, and the liquid discharge end is connected to the flanged pup joint.

A pressure compensation device with an accumulator group for controlled pressure drilling includes an electrical flat valve, a check valve, an accumulator group, a flanged pup joint and a support base. The electrical flat valve is connected to the check valve and is mounted on a top surface of the support base. The accumulator group mounted on the whole support base is a pre-storage pressure compensation device for controlled pressure drilling, and is located at a downstream position of the check valve. The liquid inlet end of the accumulator group is connected to the check valve, and the liquid discharge end is connected to the flanged pup joint.

Apparatus for regulating gas pressure suitable for use in systems and/or networks for transport and/or distribution of gas, the apparatus configured to be connected upstream with an inlet duct for the gas and downstream with an outlet duct, and includes: a main regulator including: an inlet area fluidically connectable with the inlet, an outlet area fluidically connectable with the outlet, a shutter which acts between the inlet area and the outlet area, means configured to push the shutter towards a closed position, a motorization chamber in which a movable element is housed, a pilot regulator including: an inlet which is fluidically connected with a first sub-chamber, to thus allow the passage of gas from the first sub-chamber towards an inlet of the pilot regulator, an outlet which is fluidically connected to said second sub-chamber, and at least one pilot valve.

A petroleum pipeline safety system for preventing contamination of an environmentally sensitive area close to a pipeline is provided. The system includes a first portion of the pipeline including an upstream portion of the pipeline supplying a flow of fluid material and a flow restriction downstream of the first portion of the pipeline. The system further includes a second portion of the pipeline downstream of the flow restriction, receiving the flow of fluid material from the first portion and conveying the flow of fluid material through the environmentally sensitive area to a downstream portion of the pipeline. The flow restriction is configured to create a lower pipeline internal pressure within the second portion as compared to a pipeline internal pressure within the first portion. The system further includes a third portion of the pipeline downstream of the environmentally sensitive area and including the downstream portion of the pipeline.

A petroleum pipeline safety system for preventing contamination of an environmentally sensitive area close to a pipeline is provided. The system includes a first portion of the pipeline including an upstream portion of the pipeline supplying a flow of fluid material and a flow restriction downstream of the first portion of the pipeline. The system further includes a second portion of the pipeline downstream of the flow restriction, receiving the flow of fluid material from the first portion and conveying the flow of fluid material through the environmentally sensitive area to a downstream portion of the pipeline. The flow restriction is configured to create a lower pipeline internal pressure within the second portion as compared to a pipeline internal pressure within the first portion. The system further includes a third portion of the pipeline downstream of the environmentally sensitive area and including the downstream portion of the pipeline.

A flow arrangement for a control valve can include a plurality of flow-control components that are movable relative to each other and that define at least part of a flow path from a pressure source to a dome of a pressure relief valve. The flow-control components can be movable relative to each other in response to system pressure to selectively increase or decrease the flow capacity of the flow path. In some cases, flow capacity can be increased or decreased during initial loading of the dome, at low pressures, or at higher pressures.

An air inflation device includes an inflation unit having a chamber in which air can be compressed to generate a high pressure air, and an air outlet channel communicating with the chamber. A pressure gauge unit includes a pressure gauge, a shaft extending outwardly from the pressure gauge and inserted into the air outlet channel, and a check valve sleeved on the shaft and movable between an open state for allowing the high pressure air in the chamber to flow into the air outlet channel, and a closed state for preventing the high pressure air in the air outlet channel to flow back into the chamber. An air guide unit is connected to the inflation unit for guiding the high pressure air to flow out of the air outlet channel.

A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a pull rod disposed in the bore and defining a bolt cavity. The pull rod is moveable between a first pull rod position and a second pull rod position. The valve assembly further includes a bolt disposed in the bolt cavity and moveable with respect to the pull rod between a first bolt position and a second bolt position. The valve assembly further includes a spool disposed in the bore. The spool is operatively coupled to the pull rod to move between an energized position and a neutral position.