A dual plate backflow and breakaway check valve designed to mount above grade. The dual plate check valve includes a barrel assembly having an upper portion, a lower portion and an annular groove. An upper dual valve includes an upper front plate and an upper back plate. A lower dual valve includes a lower front plate and a lower back plate. A lower valve keeper bar moves up from between a plurality of lower valve stay tabs upon breakage of the annular groove thereby allowing the lower front plate and the lower back plate to rotate about a lower valve pin and closing the lower dual valve upon a lower barrel bevel and simultaneously allowing the upper front plate and the upper back plate to rotate about an upper valve pin and closing upon an upper barrel bevel.

A dual plate backflow and breakaway check valve designed to mount above grade. The dual plate check valve includes a barrel assembly having an upper portion, a lower portion and an annular groove. An upper dual valve includes an upper front plate and an upper back plate. A lower dual valve includes a lower front plate and a lower back plate. A lower valve keeper bar moves up from between a plurality of lower valve stay tabs upon breakage of the annular groove thereby allowing the lower front plate and the lower back plate to rotate about a lower valve pin and closing the lower dual valve upon a lower barrel bevel and simultaneously allowing the upper front plate and the upper back plate to rotate about an upper valve pin and closing upon an upper barrel bevel.

A two-stage switch valve includes a valve body slidable in a flow passage of a fluid, and a spring urging the valve body upstream. The valve body includes a valve element slidable in the flow passage, an upstream guide having a ring shape and being slidable in the flow passage, and legs connecting the valve element and the upstream guide. The upstream guide is located upstream of the valve element. The legs are inclined from an axial direction of the upstream guide and extend from the upstream guide toward a center of the valve element.

A two-stage switch valve includes a valve body slidable in a flow passage of a fluid, and a spring urging the valve body upstream. The valve body includes a valve element slidable in the flow passage, an upstream guide having a ring shape and being slidable in the flow passage, and legs connecting the valve element and the upstream guide. The upstream guide is located upstream of the valve element. The legs are inclined from an axial direction of the upstream guide and extend from the upstream guide toward a center of the valve element.

A flow limiter component including a monocoque body having first, second, and third sections along a longitudinal axis. The first section includes a first end defining a first edge of the monocoque body and a bordering second end, and a first inner diameter defining a first chamber inside the first section. The second section includes a solid wall, with an orifice disposed therein, in fluid communication with the first chamber, the orifice defined by a second inner diameter. The third section includes a third end bordering the second section and a fourth end defining a second edge of the body, and a third inner diameter, the third inner diameter defining a second chamber in the third section. The second chamber is in fluid communication with the orifice. The first inner diameter is greater than the third inner diameter, and the third inner diameter is greater than the second inner diameter.

A valve includes a valve body forming a channel defining a fluid flow path extending from an inlet port to an outlet port of the valve body via a gallery disposed therebetween, an opening disposed in communication with the gallery, a valve assembly at least partially disposed through the opening and in the gallery, and a set pin having a central longitudinal axis. A valve disc of the valve assembly moves between a first position spaced from a valve seat of the valve body and a second position in contact with the valve seat. The set pin is coupled to and at least partly supported by the valve assembly to maintain the valve assembly in the first position. The fluid flow path allows a fluid to flow through the valve body in a first direction and a second direction opposite the first direction. The set pin is adapted to disengage a portion of the valve assembly when contacted by a fluid traversing the fluid flow path in the second direction, allowing the valve disc to move to the second position.

A petroleum pipeline safety system for preventing contamination of an environmentally sensitive area close to a pipeline includes an upstream portion of the pipeline supplying a flow of fluid material, a crossing portion of the pipeline receiving the flow of fluid material from the upstream portion and conveying the flow of fluid material through the environmentally sensitive area to a downstream portion of the pipeline, the downstream portion, a pipeline pressure activated valve selectively capable of blocking the flow of fluid material from entering the crossing portion based upon a change in pressure within the crossing portion, and a fluid capacitor connected to the upstream portion configured to filter out a pressure spike in the upstream portion associated with the valve blocking the flow of fluid material.

A petroleum pipeline safety system for preventing contamination of an environmentally sensitive area close to a pipeline includes an upstream portion of the pipeline supplying a flow of fluid material, a crossing portion of the pipeline receiving the flow of fluid material from the upstream portion and conveying the flow of fluid material through the environmentally sensitive area to a downstream portion of the pipeline, the downstream portion, a pipeline pressure activated valve selectively capable of blocking the flow of fluid material from entering the crossing portion based upon a change in pressure within the crossing portion, and a fluid capacitor connected to the upstream portion configured to filter out a pressure spike in the upstream portion associated with the valve blocking the flow of fluid material.

A natural gas automatic shutoff system can analyze the flow rate of natural gas through a pipe. When an anomaly is detected, the device can prevent further flow of natural gas through the pipe and can automatically notify the homeowner or authorized monitor, such as through a cell phone application or other device. Additionally, the homeowner or authorized monitor can manually control and/or monitor the flow of gas through the pipe in real-time, such as through a cell phone application or other device. At least one exemplary embodiment uses a motorized ball valve to control the flow of gas, a flow meter to measure the rate of natural gas flow through the pipe, and a microcomputer to analyze the flow and send notifications to the homeowner or authorized monitor.

A respirator directional valve (10) includes a valve housing (12), a plurality of valve flaps (16-18), which can be moved by a gas stream or by a flowing medium and are arranged at the edge, and a number of support surfaces (20-22) as a valve seat. A number of support surfaces (20-22) corresponds to a number of valve flaps (16-18). Each valve flap (16-18) is adapted to a surface of a respective support surface (20-22). The support surfaces (20-22) are sloped in relation to a cross-sectional surface through the valve housing (12). The support surfaces (20-22) together form a tip pointing in the flow direction of the respirator directional valve (10). A method for manufacturing such a respirator directional valve (10) is provided including method features relating to the use of such a respirator directional valve (10).