ASTM A105 is the standard specification for carbon steel forgings used in piping components, flanges, fittings, and valves for ambient- and higher-temperature service. Also referenced as SA-105 under the ASME Boiler and Pressure Vessel Code, A105 material is one of the most widely called-up forging specifications in oil & gas, petrochemical, and power generation piping systems. This page is part of our full bolt and fastener specifications index, see the hub for ASTM, ASME, SAE, ISO, and DIN standards across our full product range. Jade Alloys supplies ASTM A105 forged flanges, fittings, and header plugs with full material traceability and mill test certification.
ASTM A105 Material Scope
ASTM A105 covers forged carbon steel piping components for use in pressure systems operating at ambient and higher temperatures. It applies to forgings of any shape flanges, fittings, valves, and similar parts machined from forged blanks but does not cover forgings made to other dimensional standards where a different specification is called out (such as A181 for general-purpose forgings, or A350 where low-temperature notch toughness is required).
ASTM A105 Chemical Composition
Heat analysis limits per ASTM A105 material composition requirements (weight percent, maximum unless a range is shown):
| Element | Composition, % |
|---|---|
| Carbon | 0.35 max |
| Manganese | 0.60 – 1.05 |
| Phosphorus | 0.035 max |
| Sulfur | 0.040 max |
| Silicon | 0.10 – 0.35 |
| Chromium | 0.40 max (1) |
| Copper | 0.40 max (1) |
| Nickel | 0.40 max (1) |
| Molybdenum | 0.15 max (1) |
| Vanadium | 0.08 max (1) |
(1) The sum of Cr, Cu, Ni, Mo, and V shall not exceed 1.00%.
ASTM A105 Mechanical Properties
| Property | Requirement |
|---|---|
| Tensile Strength | 70 ksi (485 MPa) min |
| Yield Strength | 36 ksi (250 MPa) min |
| Elongation in 2 in. (50 mm) | 22% min |
| Reduction of Area | 30% min |
Heat Treatment of ASTM A105 Material
Forgings shall be normalized, normalized and tempered, or annealed. ASTM A105 also caps hardness at 187 HBW maximum to ensure machinability and avoid brittle microstructures. Full heat treatment records and traceability, including heat number, are provided on the mill test certificate (per ASTM A961) accompanying each shipment.
What Is A105N? (Low-Temperature Impact-Tested A105 Steel)
A105N refers to ASTM A105 material supplied in the normalized condition heated above its critical temperature and cooled in still air, refining grain structure and improving toughness and ductility over as-forged material. Normalization is not always mandatory under base A105, but it is commonly specified, and is required by many project specifications for ASME B16.5 Class 400 and higher, for low-ambient-temperature or winterized piping service, and where supplementary Charpy V-notch impact testing is called out (commonly referencing ASTM A105 Supplementary Requirement S5). Always confirm the required heat treatment condition, and any impact test temperature and acceptance values, against your project’s material requisition.
ASTM A105 Sizes & Dimensions
A105 flanges are manufactured to match the dimensional and pressure-temperature ratings of ASME B16.5 (NPS 1/2″ through NPS 24″) and ASME B16.47 (NPS 26″ and above) across pressure classes 150 through 2500. Forged fittings follow ASME B16.11, and A105 studs/bolts are typically supplied from 1/4″ up to 4″ diameter (M6 to M100 in metric) depending on flange class and bolt-circle requirements.
| Product Form | Typical Size Range | Governing Dimensional Standard |
|---|---|---|
| Flanges | NPS 1/2″ – NPS 48″ | ASME B16.5 / B16.47 |
| Forged Fittings | NPS 1/2″ – NPS 24″ | ASME B16.11 |
| Studs / Stud Bolts | 1/4″ – 4″ dia. (M6 – M100) | ASME B16.5 flange bolting tables |
| Hex Bolts / Heavy Hex Bolts | 1/4″ – 2-1/2″ dia. | ASME B18.2.1 |
| Hex Nuts / Heavy Hex Nuts | 1/4″ – 4″ dia. | ASME B18.2.2 |
ASTM A105 Equivalent Materials
A105 equivalent material designations across other standards bodies and regions:
| Standard | Designation / Relationship |
|---|---|
| ASME SA-105 | SA 105 material is functionally identical to ASTM A105, adopted directly by ASME for pressure vessel and piping code work |
| ASTM A181 | General-purpose carbon steel forgings; A105 is preferred for pressure piping applications |
| ASTM A350 Gr. LF2 | Low-temperature carbon steel forging equivalent, required when mandatory Charpy impact testing is specified |
| EN 10222-2 P250GH | Approximate European equivalent for pressure-purpose steel forgings |
| IS 2004 | Approximate Indian Standard equivalent for carbon steel forgings for general engineering and pressure-purpose applications – commonly cross-referenced against A105 on Indian EPC projects |
Applications of ASTM A105 Material
ASTM A105 forgings are specified across oil & gas pipelines and refineries, petrochemical plants, power generation piping, and general industrial pressure systems wherever carbon steel is chemically compatible with the process media and operating temperature stays within the ambient-to-moderate range covered by the specification.
Frequently Asked Questions
1. What is the difference between ASTM A105 and ASME SA-105?
2. What is A105N material?
3. Is ASTM A105 suitable for low-temperature service?
4. What is the Indian Standard equivalent to ASTM A105?
5. What heat treatment condition is ASTM A105 supplied in?
Need A105 or A105N forgings, flanges, or header plugs to a specific size or certification requirement? Contact our technical team or view the full Specifications hub.
