SLAM SHUT SAFETY DEVICE

摘要

A safety device for a gas distribution system includes a valve body, an upper casing attached to the valve body, the upper casing housing at least one spring. Further, the at least one spring is attached to a movable diaphragm that is exposed to gas system pressure. The valve body also includes a release element mounted within the valve body. The release element releasing a relatch plug when the device is activated to move a safety disc into contact with a valve seat to stop fluid from flowing when an overpressure or an underpressure condition is sensed.

主权项

1. A slam-shut safety valve comprising:
a valve body; an upper case mounted to the valve body; a diaphragm disposed between the valve body and the upper case, at least part of the diaphragm being displaceable into an interior portion of the valve body and into an interior portion of the upper case, the diaphragm having a first side being exposed to gas system pressure; a spring disposed within the interior of the upper case, the spring exerting a spring force on a second side of the diaphragm opposite the gas system pressure; a plunger connected to the first side of the diaphragm; a release element mounted within the interior of the valve body; a relatch plug operatively connected to a reset rod, the relatch plug cooperating with the release element to move a safety disc between an armed position in which the safety disc is spaced apart from a valve seat and an activated position in which the safety disc cooperates with the valve seat to prevent fluid flow through the valve seat; and, a relatch sheath cooperating with the relatch plug to guide movement of the relatch plug, wherein the relatch plug slides within the relatch sheath.