Emerson MR95 Series Instruction Manual page 9

The Type MR95H regulators have an outlet pressure
rating equal to the inlet pressure rating. Types
MR95HP and MR95HT regulators have an outlet
pressure rating lower than the inlet pressure rating.
The recommended pressure limitations are
stamped on the regulator nameplate. Some type of
overpressure protection is needed if the actual inlet
pressure exceeds the maximum operating outlet
pressure rating. Provide external overpressure
protection if the regulator inlet pressure is greater than
the safe working pressure of downstream equipment.
Common methods of external overpressure protection
include relief valves, monitoring regulators, shutoff
devices and series regulation.
Regulator operation below the maximum pressure
limitations does not preclude the possibility of damage
from external sources or from debris in the pipeline. If
the regulator is exposed to an overpressure condition,
inspect it for any damage that may have occurred.
Startup
The Specifications section and
Tables 2 and 3 show the maximum
inlet and outlet pressures for specific
constructions. Use pressure gauges to
monitor inlet pressure, outlet pressure
and any loading pressure during startup.
1. Check that proper installation is completed
and downstream equipment has been
properly adjusted.
2. Make sure all block and vent valves are closed.
3. Decompress the control spring by turning the
adjusting screw counterclockwise.
4. Slowly open the valves in the following order:
a. Loading supply and control line valve(s), if used
b. Inlet block valve
c. Outlet block valve
5. Set the regulator to the desired outlet (control)
pressure according to the Adjustment procedure.
Note
MR95 Series - AD2000 Compliant
Adjustment
▲
To avoid personal injury, property
damage or equipment damage caused
by bursting of pressure containing parts
or explosion of accumulated gas, never
adjust the control spring to produce an
outlet pressure higher than the upper
limit of the outlet pressure range for that
particular spring. If the desired outlet
pressure is not within the range of the
control spring, install a spring of the
proper range.
The factory setting of the regulator can be varied
within the pressure range stamped on the nameplate.
Follow the following procedures for the proper
adjustment of the outlet (control) spring. If the spring
range was changed, be sure to change the stamped
spring range on the nameplate.
All MR95 Series regulator springs can be backed off
to provide zero outlet. Recommended outlet pressure
ranges available, maximum inlet pressures and color
codes of the respective springs are shown in Tables 2
and 3.
Key numbers are referenced in Figure 6 or 7.
1. Loosen the jam nut (key 17).
2. Turn the adjusting screw (key 15) clockwise to
increase outlet pressure or counterclockwise to
decrease it.
3. Monitor the outlet pressure with a test gauge
during the adjustment.
4. Tighten the jam nut (key 17) to maintain the
desired setting.
Shutdown
1. Close the upstream block valve to the
regulator inlet.
2. Close the downstream block valve to the
regulator outlet.
3. Vent the downstream pressure by slowly opening
the bleed valve between the regulator and the
downstream shutoff valve. Without changing
regulator spring adjustment, all pressure between
the upstream and downstream shutoff valves will
be released through the bleed valve, since the
regulator opens in response to the decreased
outlet pressure.
WARNING
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