The SR-500 Series Pressure Reducing Regulator is designed for industrial furnaces and heating applications. These regulators will maintain a constant outlet pressure over a wide range of flows even if the inlet pressure varies. Standard construction is for clean fuel gases including Natural Gas, Propane, Butane and other Hydrocarbon fuels. Special construction is available for gases such as Coke Oven Gas. The SR-500 has a maximum operating temperature of 500°F. The standard design has internal compensation. For capacities greater than listed in the specification table the regulator can be supplied with external compensation.FEATURESPrecision outlet pressure controlWide flow rangeStainless steel valveBalance valve design - holds outlet pressure constant with varying inlet pressuresInlet pressures to 5 psigSynthetic, reinforced diaphragms - good for most fuel gasesSprings color coded for identification Maximum capacity must be limited to less than 200% of ratings below. CAPACITY TABLE Model Number Pipe Size SCFH Gas Flow @ 14.0" W.C. Pressure Drop MFD. 0.4 Sp. Gr. NAT. 0.6 Sp. Gr. AIR 1.0 Sp. Gr. L.P. 1.5 Sp. Gr. SR-12-500 1-1/2" 4,900 4,000 3,100 2,500 SR-20-500 2-1/2" 12,300 10,000 7,800 6,300 SR-24-500 3" 21,000 17,000 13,000 11,000 SR-32-500 4" 43,000 35,000 27,000 22,000 SPRING RANGES SR-500 Model Number Spring Number Spring Color Outlet Pressure Range SR-12-500 16 Orange 7" W.C. to 30" W.C. SR-20-500 Fixed No Color 0.85 psig SR-24-500 Fixed No Color 0.85 psig SR-32-500 Fixed No Color 0.50 psig Select spring for each regulator based on required system delivery pressure.