Plug valve having seal segments with booster springs

摘要

The invention is directed to a plug valve comprising a body which includes an inlet port, an outlet port and a cavity that is connected between the inlet and outlet ports; first and second seal segments which are mounted in the cavity and which each comprise a through bore that is coaxial with the inlet and outlet ports; the through bores and the inlet and outlet ports defining a flow passage through the body; a plug member which is rotatably positioned between the first and second seal segments and which includes a hole that extends transversely therethrough; the plug member being rotatable between an open position in which the hole is aligned with the flow passage and a closed position in which the hole is offset from the flow passage; and at least a first booster spring which is positioned between the first seal segment and the body to bias the first seal segment against the plug member.