Instruction manual

42
Relief Valve for Liquid Service
Type 98H – is a direct-operated relief valve for use on relief and
backpressure applications involving large LP-Gas pumping systems
and vaporizers. Internal pressure registration eliminates the need for
a control line. Body materials are available in Gray Cast Iron, Steel or
Stainless Steel. Temperature ratings are -40 to 180°F / -40 to 82°C for
CI and SST and -20 to 180°F / -29 to 82°C for Steel.
Liquid Service Relief Valves
TYPE
NUMBER
BODY
SIZE,
INCH
RELIEF PRESSURE
RANGE
RELIEF PRESSURE
SETTING
PROPANE RELIEF CAPACITY GPM / l/min AT FOLLOWING
PRESSURE BUILD-UP OVER RELIEF SETTING
5 psig / 0.34 bar 10 psig / 0.69 bar 20 psig / 1.4 bar 30 psig / 2.1 bar 50 psig / 3.4 bar
psig bar psig bar GPM l/min GPM l/min GPM l/min GPM l/min GPM l/min
98H-13 1/2 FNPT 25 to 75 1.7 to 5.2 50 3.4 10.5 39.7 15.4 58.3 21.7 82.1 25.9 98.0 30.8 117
98H-22 3/4 FNPT 70 to 140 4.8 to 9.7 100 6.9 30.8 117 49.0 185 67.9 257 79.8 302 93.1 352
98H-30 1 FNPT 70 to 140 4.8 to 9.7 100 6.9 30.8 117 49.0 185 67.9 257 79.8 302 93.1 352
Vapor Relief Valves
Type 1805 – relief valve is designed for installation between the
First and Second-Stage regulators or in the downstream line from a
high-pressure regulator used for a Final-Stage service where high
line pressures are allowed. Available in 1 or 2-inch valve bodies with
a temperature rating of -20 to 150°F / -29 to 66°C.
Type 289H – relief valve is designed for installation downstream
of larger high-pressure or low-pressure regulators in most all relief
applications. The larger diaphragm in this relief valve provides
extremely sensitive operation, with a temperature rating of -20 to
150°F / -29 to 66°C.
Types 1808 and 1808A – pilot-operated relief valve is designed to
protect large high-pressure regulators by offering extremely high
relief capacities compared to the Type 289H. The Type 1808 has a
temperature rating of -20 to 180°F / -29 to 82°C.
Vapor Relief Valves
TYPE
NUMBER
BODY SIZE,
INCH
RELIEF START-TO-
DISCHARGE
SPRING RANGE
PRESSURE
BUILDUP OVER SET
PRESSURE
CAPACITY (AIR)
psig bar psig bar psig bar SCFH Nm
3
/h
1805-18P 1 FNPT 15 1.03 5 to 35 0.34 to 2.41 15 1.03 6160 at 30 psig 161 at 2.07 bar
1805-51P 2 FNPT 15 1.03 5 to 20 0.34 to 1.38 15 1.03 28,500 at 30 psig 748 at 2.07 bar
1808-50 2 FNPT 20 1.4 15 to 40 1.03 to 2.76 10 0.69 61,600 at 30 psig 1617 at 2.07 bar
1808A-61 2 FNPT, Angle 20 1.4 15 to 40 1.03 to 2.76 10 0.69 78,230 at 30 psig 2053 at 2.07 bar
289H-42 1 FNPT 15 1.03 4 to 15 0.28 to 1.03 15 1.03 33,880 at 30 psig 889 at 2.07 bar
289H-2 2 FNPT 24 inches w.c. 60 mbar 1/2 - 2 1/4 34 to 155 mbar 1.13 78 mbar 15,400 at 2 psig 38 at 138 mbar
NOTE: Some regulators will require more than one relief valve. Consult your local Fisher
®
LP-Gas Distributor for proper relief valve sizing.
BaCKpressure regulators/relieF valves
TYPE 98H
TYPE 1805
TYPE 1808
TYPE 289H