PRESSURE RELIEF VALVES
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TheGrothModels1260A&1261APressureReliefValvesaredesignedtoprotectyourtank fromdamagecreatedbyoverpressureorexcessivevacuum.Costlyproductevaporation lossesduetonormaltank“breathing”aregreatlyreduced.Becausethe1200Series productsretaintoxicvapors,atmosphericcontaminationisminimizedwhichhelpsto provideincreasedfireprotectionandsafety.
Technical Details
•Sizes:2”(DN50)through12”(DN300)
•PressureSettings:0.5oz/in2to15psig(2.15mbargto1.03barg)
•VacuumSettings:0.5oz/in2to12psig(2.15mbargto506mbarg)
•Material:Aluminum,CarbonSteel,StainlessSteel,Fiberglass,specialmaterials availableuponrequest
Features
•ModularConstruction
•Cushionedairseating
•Superiorperformingfluoropolymerdiaphragms
•Selfdraininghousingbodyanddriprings
•PeripheralGuidingandcenterstabilizingsystemforalignment
•PEDandATEXCertified
Options
•Buna-N,FKM
•SteamJacketValve
2(50)3(76)11(48.3)8.62(219)9.37(238)7.50(191)4.12(105)5.50(140)16.62(4222)16(7)
3(80)4(102)13(57.1)10(254)11.12(282)9(229)5(127)6(152)20.25(514)22(10)
4(100)6(152)16(70.3)11(279)13.87(352)11(279)6.50(165)6.50(165)25.62(651)29(13)
6(150)8(203)16(70.3)14.50(368)17.37(441)13.5(343)8.50(216)8.50(216)34.50(876)55(25)
8(200)10(254)16(70.3)18(457)21.25(540)16(406)9.75(248)10.75(273)39.75(1010)92(42)
10(250)12(305)16(70.3)20.75(527)23.62(600)19(483)10.25(260)12.50(318)46.37(1178)105(48) 12(300)14(356)16(70.3)24.75(629)26.62(676)21(533)11(279)15(381)49.25(1251)149(68)
15
‡Onspringloadedvalves,changemodelnumber.◊150#R.F.drillingcompatibilityF.F.onaluminumandR.F.oncarbonsteelandstainlesssteelalloys. Fiberglassdimensionsonrequest.16oz/in2setwithspacer.SSsetweights-consultfactory.*Somesizesrequirenon-ferrouscomponentstoachieve0.5oz/in2setting
0.870.506.8713.325.252.782.6135175 1.000.587.3914.327.156.688.8145188
Flow Capacity Calculation
Flowcapacityvalueslistedabovearebasedonfullopen valvesat100%overpressure.Readtheflowcapacityat 100%overpressuredirectlyfromthetableabove.Use linearsted.Iftheallowableoverpressureislessthan 100%,modifytheflowcapacityusingtheappropriate“C” factorfromthetable.Ifallowableoverpressureismore than100%,consultyourGrothRepresentative.
Calculatethepercentageoverpressurebythefollowing formula.Notethatallpressuresaregaugepressure expressedinthesameunitsofmeasure.
500.720.730.730.740.750.750.760.770.770.78 600.780.790.800.800.810.810.820.820.830.84 700.840.850.850.860.860.870.880.880.890.89 800.900.900.910.910.920.920.930.930.940.94 900.950.950.960.960.970.970.980.990.991.00 AirFlowCapacityat100%Overpressure(DoubleSetPressure)
Pf=Flowingpressure
Ps=Setpressure%OP=[(Pf-Ps)/Ps]x100
Calculateflowcapacityatlessthan100%overpressure accordingtothefollowingexample.
Example Flow Capacity Calculation
Example to find “C” factor from table: Read“C”factorfor75%overpressureatintersectionof row70andcolumn5
“C”factorat75%OP=0.87
6”Model1260A1.ReadflowcapacityatsetpressurefromtableFlow=112,000SCFH
4InWCsetpressure[Ps]2.Calculateoverpressure%OP=[(7-4)/4]x100=75%
7InWCflowingpressure[Pf]3.Read“C”factorfromtable“C”=0.87
4.CalculateflowcapacityFlow=0.87x112,000=97,440SCFH “C”FactorTable %OP0123456789 100.420.430.440.450.460.460.470.480.490.50 200.510.520.520.530.540.550.560.560.570.58 300.590.590.600.610.610.620.630.640.640.65
222.160.190.370.711.482.333.804.93 504.900.290.561.072.233.505.727.42
30029.40.701.382.585.338.4213.717.8 37536.80.781.542.885.919.4015.319.8 50049.00.901.783.306.7510.717.522.7 62561.31.001.993.677.4611.919.425.1 75073.51.092.183.998.0712.921.027.3
Flow Capacity Calculation
Flowcapacityvalueslistedabovearebasedonfullopen valvesat100%overpressure.Readtheflowcapacityat 100%overpressuredirectlyfromthetableabove.Use linearinterpolationifthesetpressureisnotlisted.Ifthe allowableoverpressureislessthan100%,modifythe flowcapacityusingtheappropriate“C”factorfromthe table.Ifallowableoverpressureismorethan100%, consultyourGrothRepresentative.
Calculatethepercentageoverpressurebythefollowing formula.Notethatallpressuresaregaugepressure expressedinthesameunitsofmeasure.
Pf=Flowingpressure
Ps=Setpressure
%OP=[(Pf-Ps)/Ps]x100
Calculateflowcapacityatlessthan100%overpressure accordingtothefollowingexample.
Example Flow Capacity Calculation
“C”FactorTable %OP0123456789
100.420.430.440.450.460.460.470.480.490.50 200.510.520.520.530.540.550.560.560.570.58 300.590.590.600.610.610.620.630.640.640.65 400.660.660.670.680.680.690.700.700.710.72 500.720.730.730.740.750.750.760.770.770.78 600.780.790.800.800.810.810.820.820.830.84 700.840.850.850.860.860.870.880.880.890.89 800.900.900.910.910.920.920.930.930.940.94
Example to find “C” factor from table: Read“C”factorfor75%overpressureatintersectionof row70andcolumn5
“C”factorat75%OP=0.87
6”Model1260A1.ReadflowcapacityatsetpressurefromtableFlow=3,140NCMH 100mmWCSetPressure[Ps]2.Calculateoverpressure%OP=[(175-100)/100]x100=75% 175mmWCFlowingPressure[Pf]3.Read“C”factorfromtable“C”=0.87
4.CalculateflowcapacityFlow=0.87x3,140=2,732NCMH
psig2(50)3(80)4(100)6(150)8(200)10(250)12(300)
Flow Capacity Calculation
Flowcapacityvalueslistedabovearebasedonfullopen valvesat100%overpressure.Readtheflowcapacityat 100%overpressuredirectlyfromthetableabove.Use linearinterpolationifthesetpressureisnotlisted.If theallowableoverpressureislessthan100%,modify theflowcapacityusingtheappropriate“C”factorfrom thetable.Ifallowableoverpressureismorethan100%, consultyourGrothRepresentative.
Calculatethepercentageoverpressurebythefollowing formula.Notethatallpressuresaregaugepressure expressedinthesameunitsofmeasure.
Pf=Flowingpressure
Ps=Setpressure %OP=[(Pf-Ps)/Ps]x100
Calculateflowcapacityatlessthan100%overpressure accordingtothefollowingexample. AirFlowCapacityat100%Overpressure(DoubleSetPressure)
Example Flow Capacity Calculation
500.630.640.650.660.670.670.680.690.700.71 600.720.720.730.740.750.760.760.770.780.79 700.800.800.810.820.820.830.840.850.850.86 800.870.870.880.890.900.900.910.920.920.93 900.940.940.950.960.960.970.970.980.991.00
Example to find “C” factor from table: Read“C”factorfor75%overpressureatintersectionof row70andcolumn5
“C”factorat75%OP=0.83
6”Model1261A1.ReadflowcapacityatsetpressurefromtableFlow=448,000SCFH
4psigSetPressure[Ps]2.Calculateoverpressure%OP=[(7-4)/4]x100=75%
7psigFlowingPressure[Pf]3.Read“C”factorfromtable“C”=0.83
4.CalculateflowcapacityFlow=0.83x448,000=371,840SCFH
barg2(50)3(80)4(100)6(150)8(200)10(250)12(300)
0.070.821.572.726.1610.115.521.7 0.100.991.893.287.4512.218.826.2 0.151.232.364.099.2815.223.432.6 0.201.432.764.8010.917.927.438.3 0.251.623.145.4412.320.331.143.4 0.301.793.486.0413.722.534.548.2 0.351.953.816.6115.024.637.852.7 0.402.104.127.1416.226.640.957.0 0.452.254.417.6617.428.543.861.1 0.502.394.708.1618.530.446.665.1 0.552.524.988.6419.632.249.468.9 0.602.655.259.1020.633.952.172.6 0.702.895.7610.022.737.257.279.7 0.803.136.2510.824.640.462.186.5 0.903.356.7211.726.543.566.793.1 1.003.567.1812.528.346.471.299.4
Flow Capacity Calculation
Flowcapacityvalueslistedabovearebasedonfullopen valvesat100%overpressure.Readtheflowcapacityat 100%overpressuredirectlyfromthetableabove.Use linearinterpolationifthesetpressureisnotlisted.If theallowableoverpressureislessthan100%,modify theflowcapacityusingtheappropriate“C”factorfrom thetable.Ifallowableoverpressureismorethan100%, consultyourGrothRepresentative.
Calculatethepercentageoverpressurebythefollowing formula.Notethatallpressuresaregaugepressure expressedinthesameunitsofmeasure.
Pf=Flowingpressure
Ps=Setpressure
%OP=[(Pf-Ps)/Ps]x100
Calculateflowcapacityatlessthan100%overpressure accordingtothefollowingexample.
Example Flow Capacity Calculation
600.720.720.730.740.750.760.760.770.780.79 700.800.800.810.820.820.830.840.850.850.86 800.870.870.880.890.900.900.910.920.920.93 900.940.940.950.960.960.970.970.980.991.00
Example to find “C” factor from table: Read“C”factorfor75%overpressureatintersectionof row70andcolumn5
“C”factorat75%OP=0.83
6”Model1261A1.ReadflowcapacityatsetpressurefromtableFlow=16,200NCMH
0.4bargSetPressure[Ps]2.Calculateoverpressure%OP=[(0.7-0.4)/0.4]x100=75%
0.7bargFlowingPressure[Pf]3.Read“C”factorfromtable“C”=0.83
4.CalculateflowcapacityFlow=0.83x16,200=13,446NCMH
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Foreasyordering,selectpropermodelnumbers MODEL#NOMINALSIZEMATERIALOPTIONS
1260AWeightLoaded 1261APressureSpring
PalletMaterial
SeatMaterial
BodyMaterial
1=Aluminum
3=CarbonSteel
5=StainlessSteel
6=VinylEsterResin
7=Furan
Z=Special
Notes
•Includemodelnumberandsettingwhenordering.
•Forspecialoptions,consultfactory.
•Whenorderingsteamjacket,includesteampressure/temperature.
*Stainlesssteelguides,stemsarestandardwithaluminumandcarbonsteelbodies.
Stainlesssteelseatsstandardwithcarbonsteelbodies
Indicatesa2”Model1260AwithAluminumBodyandSeat,StainlessSteelPallet,FluoropolymerSeatDiaphragm,andnootheroptions.
O=NoOptions
Z=SpecialOptions
O=NoJacket
J=SteamJacket
S=Spacer
H=SteamJacket& Spacer
DiaphragmMaterial (Seat):
B=Buna-N
T=Fluoropolymer
V=FKM
Z=Special