Installation Guide
D104615X014
April 2022
MR98 Series AD2000 Compliant
D-A-CH Region Only
Introduction
This Installation Guide provides instructions for
installation, startup and adjustment. To receive a
copy of the Instruction Manual, contact your local
Sales Office or view a copy at www.emerson.
com. For further information, refer to MR98 Series
Backpressure Regulators and Relief valves Instruction
Manual, D104615X012 (D.A.CH. Region Only).
PED Category
This product may be used as a safety accessory
with pressure equipment in the following Pressure
Equipment Directive. It may also be used outside
of the Pressure Equipment Directive using Sound
Engineering Practice (SEP) per table below. For
information on the current PED revision, see Bulletin:
(D.A.CH. Region Only).
Specifications
Available Constructions
Type MR98H:
Backpressure regulator/relief valve
for spring settings range from 0.34 to 13.8 bar /
5 to 200 psig.
Type MR98HH:
Backpressure regulator/relief
valve for spring settings range from 10.3 to
25.9 bar / 150 to 375 psig.
Body and Orifice Sizes
DN 15 / 1/2 in. body:
10.56 mm / 0.416 in. orifice
DN 20 and 25 / 3/4 and 1 in. bodies:
16.02 mm / 0.631 in. orifice
DN 40 and 50 / 1-1/2 and 2 in. bodies:
29 mm / 1.142 in. orifice
End Connection Styles
G Thread and Integral PN 16/25/40 RF; all
flanged sizes are fabricated with a 356 mm / 14 in.
face-to-face dimension.
Set Pressure Ranges
(1)
See Table 1
Maximum Cold Working Pressures of Body Size
and Materials
(1)(6)
See Table 2
Maximum Inlet, Outlet and Spring Case
Pressure Ratings
(1)
See Table 2
Temperature Capabilities of Body Materials
(1)(2)
Temperature Capabilities of Trim Materials
(1)(2)
Flow Coefficients
IEC Sizing Coefficients
Pressure Registration
Internal or External
Shutoff Classification Per ANSI/FCI 70-3-2004
Metal Seats:
Class IV
PTFE:
Class IV
Elastomer Seats:
Class IV or better
TYPE
PRODUCT SIZE
BODY
MATERIAL
CATEGORY
MR98H/
MR98HH
DN 15 to 25 /
1/2 to 1 in.
Stainless steel
SEP
MR98H
DN 40 and 50 /
1-1/2 and 2 in.
Stainless steel
II
BODY MATERIAL
TEMPERATURE RANGE
Stainless steel
(4)
-40 to 232°C / -40 to 450°F
TRIM MATERIAL
PART
TEMPERATURE RANGE
Seat
Diaphragm
O-ring
Diaphragm
Protector
°C
°F
Nitrile (NBR)
-40 to 82
-40 to 180
Neoprene (CR)
-40 to 82
-40 to 180
Fluorocarbon (FKM)
(3)
-18 to 149
(5)
0 to 300
(5)
Ethylenepropylene
(EPDM)
-7 to 135
20 to 275
Perfluoroelastomer
(FFKM)
-18 to 218
0 to 425
Polytetrafluoroethylene
(PTFE)
-40 to 204
-40 to 400
Metal
-40 to 450
-40 to 232
BODY SIZE
C
V
C
g
C
1
DN
In.
15
1/2
3.4
120
35.3
20 and 25
3/4 and 1
6.5
250
38.5
40 and 50
1-1/2 and 2
20.0
780
39.0
BODY SIZE
X
T
F
d
F
L
K
m
DN
In.
15
1/2
0.787
0.78
0.94
0.88
20 and 25
3/4 and 1
0.935
0.70
0.91
0.83
40 and 50
1-1/2 and 2
0.961
0.69
0.94
0.88
1. The pressure/temperature limits in this Installation Guide and any applicable standard or code limitation should not be exceeded.
2. Pressure and/or the body end connection may decrease these maximum temperatures.
3. Not for use on steam service.
4. Meets API 614 Requirements (with stainless steel trim).
5. Limited to 93°C / 200°F for hot water.
6. Temperature, trim material and/or the body end connection may decrease these maximum pressures.
