SB Relief Regulators are versatile - offering fast, positive response service for air, all types of gas fuels, and inert gas applications. They may be used as bypass valves in automatic safety systems, and as high capacity relief regulators downstream of reducing regulator stations and inert gas generators. Supplied with color-coded springs in cataloged pressure ranges. Inlet pressures to 25 psig operating; maximum surge to 50 psig without damage. Available in sizes 3/4 '' through 3'' NPT. FEATURESDrip tight shut-off below start to open point Balanced valve designSynthetic reinforced diaphragms - for air, all fuel and inert gasesInlet pressures to 25 psig operating, maximum surge to 50 psig without damageRugged proven designStandard SB series operating temperatures to 150°F CAPACITY TABLE Relief Regulator Catalog Number Pipe Size NPT Capacities in SCFH of Various Specific Gravity Gases @ 14" W.C. Pressure Drop 0.4 0.6 1.0 1.5 2.0 SB 6 3/4" 1,230 1,000 780 630 550 SB 8 1" 2,400 2,000 1,500 1,200 1,100 SB 12 1-1/2" 4,900 4,000 3,100 2,500 2,200 SB 20 2-1/2" 12,300 10,000 7,800 6,300 5,500 SB 24 3" 21,000 17,000 13,000 11,000 9,200 SPRING RANGES Spring Number Spring Color Spring Adjustment Range Start to Stroke Setting Minimum Maximum 4 Red 1" W.C. 8" W.C. 16 Orange 7" W.C. 30" W.C. 48 White 12 osi 48 osi Spring #48 not available on #SB20 and SB24