Types 98LD and 98HD
4
CO
MP
METAL
Figure 3. Installation Schematics for Types 98LD and 98HD Relief Valves
Table 1. Differential Relief Pressure Ranges
BODY SiZE,
inCHES (Dn)
TYPE 98LD
(1)
TYPE 98HD
(1)
COLOR
CODE
PaRT
nUMBER
SPRing WiRE
DiaMETER,
inCHES (mm)
SPRing FREE
LEngTH,
inCHES (mm)
Psi
bar
Psi
bar
1/4
2 to 7
6 to 14
12 to 25
20 to 38
0,14 to 0,48
0,41 to 0,97
0,83 to 1,7
1,4 to 2,6
15 to 35
25 to 75
70 to 140
130 to 200
1,03 to 2,4
1,7 to 5,2
4,8 to 9,7
9,0 to 13,8
Yellow
Green
Red
Blue
1E392527022
1E392627012
1E392727142
1L346127142
0.148 (3,76)
0.170 (4,32)
0.207 (5,26)
0.225 (5,72)
2.00 (50,8)
2.00 (50,8)
1.93 (49,0)
2.08 (52,8)
1/2 (15)
2 to 7
6 to 14
12 to 25
20 to 38
0,14 to 0,48
0,41 to 0,97
0,83 to 1,7
1,4 to 2,6
15 to 35
25 to 75
70 to 140
130 to 200
1,03 to 2,4
1,7 to 5,2
4,8 to 9,7
9,0 to 13,8
Yellow
Green
Red
Blue
1E395627022
1D7455T0012
1E395727192
1L380027142
0.207 (5,26)
0.234 (5,94)
0.281 (7,14)
0.331 (8,41)
2.50 (63,5)
1.02 (25,9)
2.44 (62,0)
2.25 (57,2)
3/4 and 1
(20 and 25)
2 to 7
6 to 14
12 to 25
20 to 38
0,14 to 0,48
0,41 to 0,97
0,83 to 1,7
1,4 to 2,6
15 to 35
25 to 75
70 to 140
130 to 200
1,03 to 2,41
1,7 to 5,2
4,8 to 9,7
9,0 to 13,8
Yellow
Green
Red
Blue
1E398927022
1E399027142
1E399127162
1L380127092
0.306 (7,77)
0.343 (8,71)
0.406 (10,3)
0.468 (11,9)
4.00 (102)
4.00 (102)
4.00 (102)
3.75 (95,3)
1-1/2 and 2
(40 and 50)
- - - -
- - - -
- - - -
- - - -
- - - -
- - - -
- - - -
- - - -
5 to 35
20 to 65
50 to 100
80 to 170
0,34 to 2,4
1,4 to 4,5
3,5 to 6,9
5,5 to 11,7
Dark Gray
Light Blue
Light Gray
Black
1E792327092
1E795327082
1E795427082
1P788827082
0.468 (11,9)
0.531 (13,5)
0.562 (14,2)
0.625 (15,9)
6.56 (167)
6.56 (167)
6.56 (167)
6.56 (167)
1. All springs may be backed off to 0 psig (0 bar). However, highest capacities and best performances are obtained by using these springs in their recommended ranges.
installation
Unbox and inspect the valve. Remove pipe scale and
other foreign material from the connecting pipeline.
Apply a suitable pipe compound to the male threads.
The relief valve can be installed in any position as long
as the flow is in the direction indicated by the arrow
cast on the body. The design of the valve isolates
diaphragm and pressure response chamber from the
main flow stream. The higher pressure is measured
inside the body through a registration hole on the inlet
side of the body. Connect the low pressure line to
the NPT connection in the spring case (see Figure 2).
This connection is 1/8 NPT for NPS 1/4 and 1/2
(DN 15) bodies, and 1/2 NPT for NPS 3/4 and 1
(DN 20 and 25) bodies.
Maximum operating temperatures for the Types 98LD and
98HD relief can be seen in the Specifications section.
!
WaRning
Personal injury or system damage may
result if this relief valve is installed where
service conditions could exceed the limits
given on the Specifications section
or regulator nameplate. installations
should be adequately protected from
physical damage.
Overpressuring any portion of this
equipment may cause equipment damage,
leaks in the relief valve, or personal injury
due to bursting of pressure-containing
parts. System operation within the limits
shown in the Specifications section does
not eliminate the possibility of damage
from external sources or debris in the
B0878-2
LOW PRESSURE
(FOR LOaDing)
RELiEF OUTLET anD
OPTiOnaL PiPing TO
SYSTEM
LOaDing
PRESSURE
UnCOnTROLLED
LOW PRESSURE
PUMP
HigH
PRESSURE
COnTROLLED
HigH PRESSURE
COnTROLLED
HigH PRESSURE
