UNA VALVULA DE BOLA CON UN SELLO RESISTENTE AL FUEGO

摘要

A ball valve is disclosed having two seat rings on each side of the closure member. Each seat ring is operative independently of the other and each ring is sealed with respect to both the ball and with respect to the body independently of the other seat ring. One of the seat rings employes metallic fire resistant seals to seal with respect to both the body and the ball.