A105 /A105N/A350 Lf2/A350 Lf3/A694 F42 F46 F52 F60 F65 F70 Carbon Steel Blind/Welding Neck/Slip on Flange

Product Description

Carbon steel forgings, manufactured in accordance with ASTM/ASME A/SA105, are generally used for piping applications. These forged carbon steel piping components (including flanges, fittings, and valves, etc) are used for ambient- and higher-temperature service in pressure systems. The A105N, which is designated with a suffix "N", denotes that the A105 forging shall be furnished in normalized condition. If the forgings are used for piping applications of ASME BPVC or ASME B31, the material shall be its identical equivalent of SA-105 or SA-105N. In short, the heat treatment of normalization distinguishes A105N from A105, or SA-105N from SA-105.
Although normalization is a prevalent heat treatment procedure for ASTM A105 forgings, it is not a mandatory requirement except for the following piping components:

For ASTM A105 flanges manufactured in accordance with ASME B16.5 or ASME B16.47, if the pressure rating is above Class 300, normalization is a must.

For A105 flanges of special design where the design pressure at the design temperature exceeds the pressure-temperature ratings of Class 300, Group 1.1, or special design where the design pressure or design temperature are not known, normalization is also required.
For piping components other than flanges that are made from A105 forgings, if the size is over NPS 4 and the pressure rating is above Class 300, normalization is required. If the working pressure at the operating temperature exceeds the tabulated values for special Class 300 of Group 1.1, ASTM A105N shall be applied.

Q: Can ASTM A105 Forgings Be Used for Tubesheets?
A: ASTM A105/ A105M, identical with ASME SA-105/ SA-105M, is the standard specification for carbon steel forgings for piping applications. The application of ASME SA-105 forgings is endorsed by a series of ASME Boiler and Pressure Vessel Codes and ASME B31 Codes. However, the misuse of this material is commonly seen in some engineering practices. A typical misuse is that some fabricators may manufacture tubesheets from ASTM A105/ ASME SA-105 forgings by mistake.
In the standard specification, it states clearly in para 1.1 that "tubesheets and hollow cylindrical forgings for pressure vessel shells are not included within the scope of this specification". Hence ASTM A105/ ASME SA-105 forgings CAN'T be used for the manufacture of tubesheets. The tubesheet is an important pressure vessel component for heat exchangers, heaters, superheaters and evaporators, etc. For a carbon steel tubesheet, if it is not allowed to be made from A105, what material should it be made from? The answer is ASTM A266 or ASME SA-266 forging as stated in para. 1.3.

CHEMICAL REQUIREMENTS ASTM/ASME A/SA105

Element	Composition, %
Carbon	0.35 max
Manganese	0.60-1.05
Phosphorus	0.035 max
Sulfur	0.040 max
Silicon	0.10-0.35
Copper	0.40 max (1)
Nickel	0.40 max (1)
Chromium	0.30 max (1-2)
Molybdenum	0.12 max (1-2)
Vanadium	0.08 max
(1) The sum of copper, nickel, chromium, molybdenum and vanadium shall not exceed 1.00%. (2) The sum of chromium and molybdenum shall not exceed 0.32%. Note: For each reduction of 0.01% below the specified carbon maximum (0.35%), an increase of 0.06% manganese above the specified maximum (1.05%) will be permitted up to a maximum of 1.35%.

Mechanical Properties of ASTM A105 Materials

Tensile Strength min.		Yield Strength min.		Elongation min.	Reduction of Area, min.	Hardness
MPa	ksi	MPa	ksi	%	%	HB
485	70	250	36	22	30	137-187