| 摘要 |
A pressure relief valve for a pressurized fluid system in which a compression spring is used to seal a compression shaft in communication with a front bushing having a O-ring seal is provided. The relief valve automatically relieves overpressure conditions and automatically resets to a closed, leak proof after an overpressure event subsides. The compression shaft is also in communication with an indicator pin, which is pushed out of the body of the relief valve during an overpressure event, and remains pushed out until manually reset, thus indicating that an overpressure event has occurred, even after the overpressure event has subsided. |
| 主权项 |
1. A resettable fluid over-pressurization indicator system configured to return over-pressurized fluid to a pressurized or unpressurized source of fluid regardless of the physical position of the source relative to the indicator, the resettable fluid over-pressurization indicator system comprising:
a generally tubular body comprising a first end configured to be in fluid communication with a pressurized system pipe and a second end configured to house a reciprocating indicator pin through a pin aperture therein, the tubular body further comprising a central bore comprising a vent aperture, between the first end and the second end, configured to permit the discharge of over-pressurized fluid from the pressurized system pipe; a housing rotatably secured to the exterior of the generally tubular body, the housing enclosing the vent aperture and in fluid communication with the vent aperture regardless of the rotatable position of the housing, the housing further comprising an outlet configured to be in fluid communication with the fluid source when in use; and a piston pin indicator assembly configured to reside within the central bore, the piston assembly configured for actuation in response to over-pressurization of a fluid in the pressurized system pipe downstream from the fluid source, the piston pin assembly comprising a piston connected to a spring having a compression coefficient sufficiently low to compress in response to exposure of the spring to the over-pressurized fluid from the pressurized system pipe so as to actuate a resettable indicator pin to indicate the occurrence of over-pressurization of the pressurized pipe system even after the occurrence of the over-pressurization ceases until the pin is manually reset, but where the compression coefficient is sufficiently high to withstand compression by any back pressure from the source of fluid, the piston indicator assembly being configured to permit the indicator pin to be manually reset, such that the system provides visual indication of over-pressurization of the pressurized fluid without giving a false positive based upon over-pressurization of the fluid source. |
