4.2 SYMPTOMS OF FAULTY OPERATION
The following signs indicate faulty operation: the necessary
r e p a i r s should be made immediately.
a. With no flow through the hose, working pressure in-
creases steadily above set pressure - indicates a leak across
b. Continuous discharge of gas from relief valve - indicates
a relief valve failure or seat failure.
c . Gas leakage from spring case - indicates loose or
d. Gas leakage from pressure gauge - indicates a damaged
gauge or a loose connection. If the gauge leaks, it must be
replaced immediately with a new gauge free of oil and grease.
e. Gas leakage from inlet connection - indicates a dam-
aged gland or a loose connection.
f. An excessive drop in indicated cylinder pressure as the
f l o w is increased - indicates a dirty inlet filter or that the
cylinder valve is not fully open. If the inlet filter cannot be
cleaned with compressed nitrogen, replace the gland.
4.3 DIAPHRAGM REPLACEMENT
a. Disconnect the regulator from the cylinder.
b. Mount the regulator vertically with the spring case as-
sembly UP. If it is more convenient, brace the regulator by
holding the forged body section with an 11/16-inch wrench,
and the spring case with a 1 l/4-inch wrench.
c. Remove the spring case and screw assembly carefully
by unscrewing it from the regulator body.
screw is preset in the spring case and tension on the adjust-
ing spring cannot be relieved.
d. Lift off the spring button, adjusting spring, diaphragm
plate, and slip ring.
e. Lift the diaphragm and thrust plate assembly out of the
regulator body by gripping it by the raised center section.
f. Replace the diaphragm.
Before discarding the old
diaphragm, pop out the thrust plate by doubling the diaphragm
g. Reinsert the thrust plate by pushing the edge of t h e
plate under the retaining lip on one side and gradually work-
ing the lip around over the thrust plate.