Material Grade

A 350

The Forged carbon and low-alloy steel forged or ring-rolled flanges, forged fittings and valves intended primarily for low-temperature service and requiring notch toughness testing. They are made to specified dimensions, or to dimensional standards, such as the ASME and API Specifications referenced in Section 2. Although this specification covers some piping components machined from rolled bar and seamless tubular materials, it does not cover raw material produced in these product forms.

Specifications

Standard	ASTM A 350/A 350M

Chemical Composition

	LF1	LF2	LF3	LF5	LF6	LF9	LF787
C	0.30	0.30	0.20	0.30	0.22	0.20	0.07
Mn	0.6 to 1.35	0.6 to 1.35	0.90 max	0.6 to 1.35	1.15 to 1.5	0.40 to 1.06	0.40 to 0.70
P	0.035	0.035	0.035	0.035	0.025	0.035	0.025
S	0.04	0.04	0.04	0.04	0.025	0.04	0.025
Si	0.15 to 0.30	0.15 to 0.30	0.20 to 0.35	0.20 to 0.35	0.15 to 0.30	. . .	0.04 max
Ni	0.40 max	0.40 max	3.3 to 3.7	1.0 to 2.0	0.40 max	1.6 to 2.24	0.70 to 1.0
Cr	0.30 max	0.30 max	0.30 max	0.30 max	0.30 max	0.30 max	0.06 to 0.90
Mo	0.12 max	0.12 max	0.12 max	0.12 max	0.12 max	0.12 max	0.15 to 0.25
Cu	0.040 max	0.040 max	0.040 max	0.040 max	0.040 max	0.75 to 1.25	1.00 to 1.30
Co	0.40 max	0.40 max	0.40 max	0.40 max	0.40 max	0.02 max	0.02 min
V	0.08 max	0.08 max	0.03 max	0.03 max	0.04 to 0.11	0.03 max	0.03 max
N	. . .	. . .	. . .	. . .	0.01–0.030	. . .

* When vacuum carbon-deoxidation is required by Supplementary Requirement S4, the silicon content shall be 0.12 % maximum.
* The sum of copper, nickel, chromium, vanadium and molybdenum shall not exceed 1.00 % on heat analysis.
* The sum of chromium and molybdenum shall not exceed 0.32 % on heat analysis.
* By agreement, the limit for columbium may be increased up to 0.05 % on heat analysis and 0.06 % on product analysis.

Mechanical & Physical Properties

Property	Values

Ultimate Tensile Strength	485 – 655 Mpa

0.2% Yield Strength	250 Mpa

Elongation	22% min

Reduction of Area	30% min

Charpy Impact Toughness	20 average/16min J at-46o C

Hardness	197 HB max