High Yield Flanges (ASTM A694)

ASTM A694 is the standard specification to cover carbon and alloy steel forgings for pipe flanges, fitting, valves and other parts for high-pressure transmission service.  Applications include, but are not limited to, in wellhead and Christmas-tree manifold equipment in oil and gas industry.  The two numbers in each grade indicate the yield strength requirements, in ksi. 

Chemical Composition

Element F42 Content, % F52 Content, % F60 Content, % F65 Content, % F70 Content, %
Carbon (C) 0.13~0.20 0.16~0.22 0.17~0.23 0.17~0.23 0.06~0.10
Silicon (Si) 0.20~0.40 0.15~0.40 0.15~0.40 0.15~0.40 0.20~0.40
Manganese (Mn) 1.20~1.60 1.10~1.40 1.20~1.50 1.30~1.60 1.10~1.40
Phosphorous (P) ≤ 0.030 ≤ 0.025 ≤ 0.020 ≤ 0.025 ≤ 0.020
Sulfur (S) ≤ 0.020 ≤ 0.012 ≤ 0.012 ≤ 0.015 ≤ 0.010
Molybdenum (Mo)   0.20~0.35 0.45~0.60 0.45~0.65 1.20~1.70
Nickel (Ni) ≤ 0.30 ≤ 0.50 0.40~1.00 ≤ 0.30 0.20~0.40
Chromium (Cr) ≤ 0.30 ≤ 0.30 ≤ 0.25 ≤ 0.30 ≤ 0.30
Copper (Cu) ≤ 0.25 ≤ 0.25 ≤ 0.25 ≤ 0.25 ≤ 0.25
Vanadium (V)     ≤ 0.050   0.02~0.06
Niobium (Nb)       0.025~0.050  
Pcm         ≤ 0.25
Carbon Equivalent ≤ 0.48 ≤ 0.48 ≤ 0.48 ≤ 0.43 ≤ 0.48

 

* Heat treatment of quenching and tempering are required

Mechanical Requirements

Grade Yield Strength, Min (KSI ) Tensile Strength, Min (KSI)
F42 42 60
F46 46 60
F48 48 62
F50 50 64
F52 52 66
F56 56 68
F60 60 75
F65 65 77
F70 70 82