ASTM A105 / A105N Flanges

ASTM A105 / A105N Flanges

A105 / A105N Flanges.

A105 Flanges are used for ambient and high temperature services and by nature have hardness level and nickel content within the limit of NACE. ASTM A105 has no grade.Sometimes A105N is described. N stands not for Grade, but for normalized. Normalizing is a type of heat treatment, applicable to ferrous metals only. The purpose of normalizing is to remove the internal stresses induced by heat treating, casting, forming etc. A105 / A105N flanges are used in low and middle pressure fluid pipe line, boiler, petroleum and natural gas industry, electric industry , shipbuilding, fertilizer equipment, etc,.

Type of Flanges  

WN (Welding Neck), SO (slip on), PL (Plate), BL (Blind), Th (Threaded), SW (socket welding), LF/SE (lapped flange/stub end), LWN (long welding neck), Orifice flange, Reducing flange, etc

Nominal Chemical Requirement.

Grade	C	Mn	P	S	Si	Cu	Ni	Cr	Mo	V
A105	-	0.60	-	-	0.10	-	-	-
	0.35	1.05	0.035	0.040	0.35	0.40	0.40	0.30	0.12	0.08

Mechanical Requirement.

Grade	Condition	Tensile Strength min (MPa)	Yield Strength min (MPa)	Elongation (L = 4d%)	Reduction of Area % min	Brinell Hardness max
A105	-	485	250	22	30	187
	-

Heat Treatment:

Heat treatment is not mandatory requirement except:
1) Flanges above Class 300
2) Flanges of special design where the design pressure at the design temperature exceeds the rating of Class 300.
3) Flanges of special design where the design pressure or design temperature are not known.

Heat treatment, when required shall be annealing, normalizing OR normalizing and tempering OR quenching and tempering.