Abstract: A pressure relief device for a double isolation valve comprises a body with a valve cavity. The valve body has a pocket formed therein. A disc is disposed in the central section of the pocket. The disc is interposed between two spring-actuated seats. Each of the seats is in fluid communication with opposing valve sides. The pocket central section is in fluid communication with the valve body cavity. Each of the seats is provided with two different types of gaskets in series. In operation, reverse pressure causes retraction of the seats, thereby relieving valve body cavity overpressure.

Abstract: A pressure relief device for a double isolation valve comprises a body with a valve cavity. The valve body has a pocket formed therein. A disc is disposed in the central section of the pocket. The disc is interposed between two spring-actuated seats. Each of the seats is in fluid communication with opposing valve sides. The pocket central section is in fluid communication with the valve body cavity. Each of the seats is provided with two different types of gaskets in series. In operation, reverse pressure causes retraction of the seats, thereby relieving valve body cavity overpressure.

Abstract: A pressure relief device for a double isolation valve comprises a body with a valve cavity. The valve body has a pocket formed therein. A disc is disposed in the central section of the pocket. The disc is interposed between two spring-actuated seats. Each of the seats is in fluid communication with opposing valve sides. The pocket central section is in fluid communication with the valve body cavity. Each of the seats is provided with two different types of gaskets in series. In operation, reverse pressure causes retraction of the seats, thereby relieving valve body cavity overpressure.

Abstract: A pressure relief device for a double isolation valve comprises a body with a valve cavity. The valve body has a pocket formed therein. A disc is disposed in the central section of the pocket. The disc is interposed between two spring-actuated seats. Each of the seats is in fluid communication with opposing valve sides. The pocket central section is in fluid communication with the valve body cavity. Each of the seats is provided with two different types of gaskets in series. In operation, reverse pressure causes retraction of the seats, thereby relieving valve body cavity overpressure.

Abstract: The present invention is directed to a metal valve stem seal and sealing system comprising a valve body; a metal valve stem housed within the valve body; a bonnet member housed within the valve body; a U-shaped metal stem gasket positioned between the metal valve stem and the bonnet member, wherein the gasket has a first lip member and a second lip member each having an interior surface and an exterior surface; a metal wedge ring fitted between the first and second lip members; and, at least one metal energizing spring adjacent the wedge ring, wherein the metal energizing spring applies a sufficient force to the wedge ring to cause the wedge ring to apply a sufficient contact pressure to the first and second lip members to form a seal between the gasket and the metal valve stem and to form a seal between the gasket and the bonnet member.

Abstract: The present invention is directed to a metal valve stem seal and sealing system comprising a valve body; a metal valve stem housed within the valve body; a bonnet member housed within the valve body; a U-shaped metal stem gasket positioned between the metal valve stem and the bonnet member, wherein the gasket has a first lip member and a second lip member each having an interior surface and an exterior surface; a metal wedge ring fitted between the first and second lip members; and, at least one metal energizing spring adjacent the wedge ring, wherein the metal energizing spring applies a sufficient force to the wedge ring to cause the wedge ring to apply a sufficient contact pressure to the first and second lip members to form a seal between the gasket and the metal valve stem and to form a seal between the gasket and the bonnet member.

Abstract: A metal valve stem seal and sealing system includes a valve body, a metal valve stem housed within the valve body, a bonnet member housed within the valve body, and a U-shaped metal stem gasket positioned between the metal valve stem and the bonnet member. The gasket has a first lip member and a second lip member. The metal valve stem seal and sealing system also includes a metal wedge ring fitted between the first and second lip members and at least one metal energizing spring adjacent the wedge ring. The spring applies a sufficient force to the wedge ring to cause the wedge ring to apply a sufficient contact pressure to the first and second lip members to form a seal between the gasket and the metal valve stem and to form a seal between the gasket and the bonnet member.

Abstract: A metal valve stem seal and sealing system includes a valve body, a metal valve stem housed within the valve body, a bonnet member housed within the valve body, and a U-shaped metal stem gasket positioned between the metal valve stem and the bonnet member. The gasket has a first lip member and a second lip member. The metal valve stem seal and sealing system also includes a metal wedge ring fitted between the first and second lip members and at least one metal energizing spring adjacent the wedge ring. The spring applies a sufficient force to the wedge ring to cause the wedge ring to apply a sufficient contact pressure to the first and second lip members to form a seal between the gasket and the metal valve stem and to form a seal between the gasket and the bonnet member.