Type MR108
Instruction Manual
Form 5875
March 2015
D103247X012
www.fisherregulators.com
Type MR108 Direct-Operated
Backpressure Regulator
!
WARNINg
Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion,
fi re and/or chemical contamination
causing property damage and personal
injury or death.
Fisher
®
backpressure regulators must
be installed, operated and maintained
in accordance with federal, state and
local codes, rules and regulations
and Emerson Process Management
Regulator Technologies, Inc.
(Emerson™) instructions.
If a leak develops or if the outlet
continually vents gas, service to the
unit may be required. Failure to correct
trouble could result in a hazardous
condition. Only a qualifi ed person must
install or service the unit.
Installation, operation and maintenance
procedures performed by unqualifi ed
personnel may result in improper
adjustment and unsafe operation. Either
condition may result in equipment
damage or personal injury. Use qualifi ed
personnel when installing, operating
and maintaining the Type MR108
backpressure regulator.
Note
To avoid cavitation, it is recommended
that the customer follow the bulletin
capacity sizing guidelines found in
Bulletin 71.4:MR108.
Figure 1.
Type MR108 Direct-Operated Backpressure Regulators
Contents
Introduction ............................................................... 3
Specifi cations
........................................................... 2
Principle of Operation ............................................... 3
Installation ................................................................ 6
Overpressure Protection........................................... 8
Startup ...................................................................... 8
Adjustment ............................................................... 8
Shutdown.................................................................. 9
Maintenance ............................................................. 10
Parts List................................................................... 16
TyPE MR108 WITH
LOW-PRESSURE ACTUATOR
TyPE MR108 WITH
HIgH-PRESSURE ACTUATOR
P1202
P1203
