VENTIL

摘要

An expanding gate valve having seats (74) which are mechanically secured in place. The valve body has seat pockets which include undercut grooves (78) intersected by a cylindrical body cavity (24) to form a pair of openings (80) to each groove. Each valve seat has a pair of lugs (90) which may be fitted through the openings and into the undercut groove. Subsequent rotation of the seat locks the lugs in the groove to secure the seat in place in its seat pocket. Each seat is able to pivot about an axis extending between the lugs in order to compensate for irregularities in the contact surfaces of the gate or seat.