Inventors:
Harold E. Wolff - Alexandria LA
Assignee:
Dresser Industries, Inc. - Dallas TX
International Classification:
F16K 1502
Abstract:
A soft seat Y-pattern check valve (10) is disclosed which can employ the valve body pattern of a valve body (12) used for a conventional Y-pattern on-off valve (18). The narrow annular seal seat (32) present in the valve body (12) is rendered inactive to the check valve function by forming an extension of the passage through the valve with a cage (34) by forming a permanent seal between the cage and narrow annular seal seat with a permanent seal (42). The cage defines a soft seal seat (70) for cooperating with a soft seal (66) mounted in a disk (52). When fluid flows from the inlet passage to the outlet passage, the disk and soft seal are moved out of engagement with the soft seal surface. Reverse flow causes the disk and soft seal to move into sealing engagement with the soft seal surface to check reverse flow.