On this page 12 sections
What is ASTM A106 Grade A?
Quick answer
- Standard
- ASTM A106 / ASME SA106
- Minimum yield
- 205 MPa
- Product form
- Pipes
- Typical uses
- Refinery and petrochemical process piping; Steam, condensate and boiler feedwater lines
ASTM A106 covers seamless carbon steel pipe from NPS ⅛" to 48" for high-temperature service in refineries, power plants, boilers and process plants. Grade A has a minimum tensile strength of 330 MPa and minimum yield of 205 MPa. It's normally supplied hot-finished (cold-drawn pipe is heat treated) and dual-certified to ASME SA106 for code construction.
A106 pipe must be seamless, and it's tested for chemistry, tension, bending or flattening, and hydrostatic or non-destructive electric testing. It's often dual- or triple-certified with ASTM A53 Grade B and API 5L Grade B, but those are separate specifications with different scope, so certification to each must be shown on the mill certificate.
Key characteristics
- Seamless only
- For high-temperature service
- Often dual-certified A106/A53/API 5L
- Available IBR and non-IBR
What does the A106 Gr A specification cover?
ASTM A106 Grade A: summary
- Standard
- ASTM A106 / ASME SA106
- Product form
- Pipes
- Size range
- NPS ⅛" to 48" and larger (DN 6 – DN 1200+), schedules 5S to XXS, single random, double random and cut lengths
- Certificates
- EN 10204 3.1; 3.2 on request
- IBR
- IBR and non-IBR supply on request (IBR explained)
What is the chemical composition of A106 Gr A?
| Element | Limit (%) |
|---|---|
| C | 0.25 max |
| Mn | 0.27 – 0.93 |
| P | 0.035 max |
| S | 0.035 max |
| Si | 0.10 min |
| Cr | 0.40 max |
| Cu | 0.40 max |
| Mo | 0.15 max |
| Ni | 0.40 max |
| V | 0.08 max |
What are the mechanical properties of A106 Gr A?
| Property | Value |
|---|---|
| Tensile strength | 330 MPa (48 ksi) |
| Yield strength (0.2% offset) | 205 MPa (30 ksi) |
| Elongation | Per formula in A106 (typical 30% longitudinal for standard specimens) |
How much pressure can A106 Gr A pipe take?
Barlow's formula (P = 2·S·t / D) gives a quick indication of pressure capacity. With the ASTM A106 Grade A minimum yield of 205 MPa, the table shows the theoretical pressure at 100% of yield, and at a 0.72 design factor (the ASME B31.8 Class 1 factor) for Sch 40 and Sch 80.
| NPS | OD (mm) | Sch 40: WT → bar | Sch 80: WT → bar |
|---|---|---|---|
| NPS 2" | 60.33 | 3.91 → 266 / 191 | 5.54 → 376 / 271 |
| NPS 4" | 114.30 | 6.02 → 216 / 155 | 8.56 → 307 / 221 |
| NPS 6" | 168.28 | 7.11 → 173 / 125 | 10.97 → 267 / 192 |
| NPS 8" | 219.08 | 8.18 → 153 / 110 | 12.70 → 238 / 171 |
| NPS 10" | 273.05 | 9.27 → 139 / 100 | 15.09 → 227 / 163 |
| NPS 12" | 323.85 | 10.31 → 131 / 94 | 17.48 → 221 / 159 |
Sizes and weight chart
Outside diameters and walls follow ASME B36.10M for common sizes. Weights are calculated for ASTM A106 Grade A at 7.85 g/cm³, and actual weights vary within manufacturing tolerances.
| NPS | OD (mm) | Sch 40 | Sch 80 | Sch 160 | XXS |
|---|---|---|---|---|---|
| NPS ½" | 21.34 | 2.77 / 1.27 | 3.73 / 1.62 | 4.78 / 1.95 | 7.47 / 2.56 |
| NPS ¾" | 26.67 | 2.87 / 1.68 | 3.91 / 2.19 | 5.56 / 2.89 | 7.82 / 3.64 |
| NPS 1" | 33.40 | 3.38 / 2.50 | 4.55 / 3.24 | 6.35 / 4.24 | 9.09 / 5.45 |
| NPS 1¼" | 42.16 | 3.56 / 3.39 | 4.85 / 4.46 | 6.35 / 5.61 | 9.70 / 7.76 |
| NPS 1½" | 48.26 | 3.68 / 4.05 | 5.08 / 5.41 | 7.14 / 7.24 | 10.15 / 9.54 |
| NPS 2" | 60.33 | 3.91 / 5.44 | 5.54 / 7.49 | 8.74 / 11.12 | 11.07 / 13.45 |
| NPS 2½" | 73.03 | 5.16 / 8.64 | 7.01 / 11.41 | 9.53 / 14.92 | 14.02 / 20.40 |
| NPS 3" | 88.90 | 5.49 / 11.29 | 7.62 / 15.27 | 11.13 / 21.35 | 15.24 / 27.68 |
| NPS 4" | 114.30 | 6.02 / 16.08 | 8.56 / 22.32 | 13.49 / 33.54 | 17.12 / 41.03 |
| NPS 6" | 168.28 | 7.11 / 28.26 | 10.97 / 42.56 | 18.26 / 67.56 | 21.95 / 79.21 |
| NPS 8" | 219.08 | 8.18 / 42.55 | 12.70 / 64.64 | 23.01 / 111.26 | 22.23 / 107.92 |
| NPS 10" | 273.05 | 9.27 / 60.30 | 15.09 / 96.00 | 28.58 / 172.31 | 25.40 / 155.13 |
| NPS 12" | 323.85 | 10.31 / 79.72 | 17.48 / 132.07 | 33.32 / 238.73 | 25.40 / 186.95 |
Quick weight calculator (density 7.85 g/cm³)
Testing and documentation
- Specification
- ASTM A106 / ASME SA106
- Size range
- NPS ⅛" to 48" and larger (DN 6 – DN 1200+), schedules 5S to XXS, single random, double random and cut lengths
- Finish
- Annealed & pickled, bright annealed, mill finish, black, varnished, galvanised or 3LPE / FBE coated (by material)
- Ends
- Plain end (PE), bevelled end (BE, ASME B16.25), threaded (NPT / BSP), grooved
Testing & documents
- Chemical and mechanical (tension, flattening, flare/bend) tests
- Hydrostatic test or non-destructive electric test (UT/ET) on each length
- Dimensional and visual inspection
- Intergranular corrosion (stainless), impact (low-temperature), hardness (sour service) when specified
- PMI and third-party inspection on request
- EN 10204 3.1 certificate; 3.2 with third-party inspection
Where is A106 Gr A used?
- Refinery and petrochemical process piping
- Steam, condensate and boiler feedwater lines
- Power-plant piping (ASME B31.1)
- Oil and gas processing facilities
- High-temperature hydraulic and air lines
Industries
What to include in your enquiry
- Specification and grade: ASTM A106 Grade A
- NPS × schedule (or OD × WT), seamless/welded, length, ends
- Quantity and destination
- Tests and certificates (3.1 / 3.2); IBR if required
Explore more
Carbon Steel pipes
Guides
Frequently asked questions
Is ASTM A106 Grade A seamless?
Yes. ASTM A106 covers seamless pipe only. Welded carbon steel pipe is supplied to other specifications such as A53 Type E or API 5L.
Can A106 Grade A be supplied IBR certified?
Yes, when required. IBR certification applies to the specific consignment, with inspection-authority documentation, so state IBR requirements on your enquiry.
What is ASTM A106 Grade A used for?
Refinery and petrochemical process piping, Steam, condensate and boiler feedwater lines, Power-plant piping (ASME B31.1), Oil and gas processing facilities.
What is the minimum yield strength of ASTM A106 Grade A?
205 MPa (205 MPa (30 ksi)), with a minimum tensile strength of 330 MPa (48 ksi).
How do I calculate the weight of ASTM A106 Grade A pipe?
kg/m = π × (OD − WT) × WT × 7.85 / 1000 for carbon steel, with dimensions in mm. See the weight chart on this page.
Is ASTM A106 Grade A available with IBR certification?
Yes, when required. IBR certification applies to the specific consignment, with inspection-authority documentation.
Which documents are supplied with ASTM A106 Grade A?
EN 10204 3.1 mill test certificate as standard, with 3.2 and third-party inspection on request.