(under subclass 479) Apparatus which includes means to compensate for atmospheric pressure differential in addition to flow responsive means within the flow line.
(1) Note. The valves are usually an unbalanced butterfly with a pressure reactor in the wall of the flow line.
SEE OR SEARCH THIS CLASS, SUBCLASS:
81, for system control responsive to changes in atmospheric pressure.
111+, for self-controlled branched flow systems having plural inflows.
484, for unbalanced butterfly valves without suction compensation means.
