Installation - Emerson Fisher 299H Series Instruction Manual

299H Series
pressure exceeds the pilot spring setting and forces the
diaphragm down, closing the orifice (C). The loading
pressure acting on the main diaphragm (E) bleeds to the
downstream system through a bleed restriction (H).
With a decrease in loading pressure on top of the main
diaphragm (E), the main closing spring (B) exerts an
upward force on the diaphragm post which is
connected to the main diaphragm (E), pulling it upward.
This moves the main valve disk toward its seat,
decreasing flow to the downstream system.
Type 299HR
During normal operation the Type 299HR performance
is identical to the Type 299H. If an overpressure
condition occurs, the pilot diaphragm head will
separate from the pilot diaphragm post and travel until
it contacts the pilot spring case. The movement of the
diaphragm head creates a path and a token, or small
amount of gas will be released.
When the overpressure condition ceases the pilot
diaphragm head will return to the diaphragm post, and
the regulator will return to normal operation.

Installation

Personal injury, equipment damage, or
leakage due to escaping gas or bursting
of pressure-containing parts might result
if this regulator is overpressured or is
installed where service conditions could
exceed the limits for which the regulator
was designed, or where conditions
exceed any ratings of the adjacent piping
or piping connections. To avoid such
injury or damage, provide pressure-
relieving or pressure-limiting devices (as
required by the appropriate code, regula-
tion, or standard) to prevent service
conditions from exceeding those limits.
A regulator may vent some gas to the
atmosphere in hazardous or flammable
gas service. Vented gas might accumulate
and cause personal injury, death or
property damage due to fire or explosion.
Vent a regulator in hazardous gas service
to a remote, safe location away from air
intakes or any hazardous location.
Protect the vent line or stack opening
against condensation or clogging.
4
http://www.fisher-china.com
If the regulator is exposed to an over-
pressure condition, it should be in-
spected for any damage that may have
occurred. Operation below these limits
does not preclude the possibility of
damage from external sources or from
debris in the pipeline.
Like most regulators, the 299H Series regulators have
an outlet pressure rating lower than its inlet pressure
rating. Complete downstream overpressure protection
is needed if the actual inlet pressure can exceed the
regulator outlet pressure rating or the pressure ratings
of any downstream equipment. Regulator operation
within ratings does not preclude the possibility of
damage from external sources or from debris in the
lines. A regulator should be inspected for damage
periodically and after any overpressure condition.
Clean out all pipelines before installation and check to
be sure the regulator has not been damaged or
collected foreign material during shipping.
Apply pipe compound to the male pipe threads only with
a screwed body, or use suitable line gaskets and good
bolting practices with a flanged body. This regulator
may be installed in any position desired as long as the
flow through the body is in the direction indicated by the
arrow on the body. Install a three-valve bypass around
the regulator if continuous operation is necessary during
maintenance or inspection.
Although the standard orientation of the actuator and
pilot to the main valve body is as shown in figure 1,
this orientation may be changed in 90° intervals
rotating the actuator lower casing (key 1) 90°, rotate
the elbow fitting in the same direction, and reinstalling
the cap screws. To keep the pilot spring case from
being plugged or the spring case from collecting
moisture, corrosive chemicals, or other foreign
material, the vent must be pointed down, oriented to
the lowest possible point on the spring case, or
otherwise protected. Vent orientation may be
changed by rotating the pilot spring case with respect
to the pilot body.
To remotely vent the pilot, remove the screwed-in vent
assembly (key 27) from the pilot spring case and
install obstruction-free tubing or piping into the
1/4-inch NPT vent tapping. Provide protection on a
remote vent by installing a screened vent cap into the
remote end of the vent pipe.
An upstream pilot supply line is not required because
of the integral pilot supply tubing (key 21). However,
as long as the 1/4-inch NPT tapping in the main valve
body is plugged, this tubing may be disconnected from
http://www.fisher-china.com