Alloy steel flange materials: ASTM A182 F1, F5, F9, F11, F22, F91 chemical composition, pressure rating, and mechanical properties.

 

Chrome moly flange (alloy steel) are manufactured from low alloy steel that contains, as key elements, chromium, and molybdenum. Alloy steel flanges are suitable for high temperature and high-pressure applications and feature good resistance to corrosion (all these conditions are typical for power generation). ASTM A182 alloy flanges are extremely ductile, strong and tough and easy to weld and offer oxidation and scaling resistance.

ASTM A182 ALLOY FLANGE MATERIALS CHEMICAL COMPOSITION

ELEMENT & PROPERTIES LOW ALLOY STEEL MEDIUM ALLOY STEEL
F11 CL2 F22 CL3 F5 F9
CARBON 0.10-0.20 0.05-0.15 0.15 MAX 0.15 MAX
MANGANESE 0.30-0.80 0.30-0.60 0.30-0.60 0.30-0.60
PHOSPHORUS MAX 0.040 0.040 0.03 0.030
SULFUR MAX 0.040 0.040 0.03 0.030
SILICON 0.50-1.00 0.50 MAX 0.50 MAX 0.50-1.00
NICKEL MAX 0.50
CHROMIUM 1.00-1.50 2.00-2.50 4.00-6.00 8.0-10.0
MOLYBDENUM 0.44-0.65 0.87-1.13 0.44-0.65 0.90-1.10
OPPER MA
COLUMBIUM MAX
VANADIUM MAX

 

ASTM A182 ALLOY FLANGE MECHANICAL PROPERTIES

ELEMENT & PROPERTIES LOW ALLOY STEEL MEDIUM ALLOY STEEL
F11 CL2 F22 CL3 F5 F9
TENSILE STRENGTH PSI (MPA) 70,000 (485) 75,000 (515) 70,000 (485) 85,000 (585)
YIELD STRENGTH PSI MIN 40,000 (275) 45,000 (310) 40,000 (275) 55,000 (380)
ELONGATION 2” % MIN 20 20 20 20
REDUCTION AREA % MIN 30 30 35 40
HARDNESS (HB) MAX* 143 ~ 207 156 ~ 207 143 ~ 217 179 ~ 217

 

ASTM A182 ALLOY FLANGE RECOMMENDED SERVICE

ASTM A182 ALLOY STEEL FLANGE TRADE DESIGNATION RECOMMENDED SERVICE
A182 F1 C-1/2 Mo Low Alloy Steel Non-corrosive applications Including water, oil and gases at temperatures between: -29 ~ 593ºC* (Not prolonged use > 470ºC).
A182 F2 0.75% Ni; Mo; 0.75% Cr Low Alloy Steel Non-corrosive applications including water, oil and gases at temperatures F2:-29ºC ~ 538ºC, WC5: -29ºC ~ 575ºC
A182 F11 1 1/4% Chrome; 1/2% Moly Low Alloy Steel Non-corrosive applications including water, oil, and gases at temperatures between -30ºC (-20ºF) and +593ºC (+1100ºF).
A182 F22 2 1/4% Chrome Low Alloy Steel Non-corrosive applications including water, oil and gases at temperatures between -30ºC (-20ºF) and +593ºC (+1100ºF).
A182 F5/F5a 5% Chrome; 1/2% Moly, Medium Alloy Steel Mild corrosive or erosive applications as well as non-corrosive applications at temperatures between -30ºC (-20ºF) and +650ºC (+1200ºF).
A182 F9 9% Chrome; 1% Moly, Medium Alloy Steel Mild corrosive or erosive applications as well as non-corrosive applications at temperatures between -30ºC (-20ºF) and +650ºC (+1200ºF).
A182 F91 9% Chrome; 1% Moly; V-N, Medium Alloy Steel Mild corrosive or erosive applications as well as non-corrosive applications at temperatures between -30ºC (-20ºF) and +650ºC (+1200ºF).