ASTM A106 Gr B CouplingASTM A105 · ASME B16.11 · Manufacturer, trader & exporter, India
SA-106 Gr B · Seamless carbon steel pipe
An ASTM A106 Gr B coupling is a short forged fitting that joins two pipes, for use with ASTM A106 Gr B pipe. ASTM A106 Gr B itself is a pipe or plate specification, so the matching coupling is made to ASTM A105 — which is what we supply for A106 B lines. Full couplings join two pipes; half couplings are welded to a pipe or vessel as a branch connection. Socket-weld or threaded to ASME B16.11.
- ASTM A105
- ASME B16.11
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an ASTM A106 Gr B Coupling?
- What it is
- A short forged fitting that joins two pipes
- Material
- ASTM A105
- Dimensions
- ASME B16.11
- Grade
- ASTM A106 Gr B
- Best at
- High-temperature process and steam piping in refineries and power plants
ASTM A106 Gr B Coupling Specification
| Product | ASTM A106 Gr B Coupling |
|---|---|
| Material standard | ASTM A105 |
| Dimensional standard | ASME B16.11 |
| Sizes | ⅛" – 4" (ASME B16.11) |
| Wall / class | Class 2000 / 3000 / 6000 / 9000 |
| Ends | Socket weld · NPT threaded |
| Testing | Chemical & mechanical per heat · NDT · impact where specified |
| Documents | EN 10204 3.1 or 3.2 on request / as specified in the PO |
When to Choose a Coupling
Full couplings join two pipes; half couplings are welded to a pipe or vessel as a branch connection. Socket-weld or threaded to ASME B16.11.
- Full and half couplings
- Reducing couplings
- Class 3000 / 6000 / 9000
More on choosing: Coupling guide.
ASTM A106 Gr B Coupling: Why A106 B for couplings
Full couplings join two pipes; half couplings are welded to a pipe or vessel as a branch connection. Socket-weld or threaded to ASME B16.11. In ASTM A106 Gr B, the choice usually comes down to the medium and temperature — the rows here are the points buyers check for this exact combination.
| Why this grade | Carbon and low-alloy fittings suit hydrocarbon, steam and utility lines. ASTM A106 Gr B is picked for high-temperature process and steam piping in refineries and power plants. |
|---|---|
| Typical service | Refineries — Process and steam lines. |
| Welding to carbon steel | Matching carbon or low-alloy filler is used; joints to stainless need ER309L |
| Matching filler | ER70S-6 / E7018 |
ASTM A106 Gr B Coupling Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Phosphorus | As specified |
| Sulphur | As specified |
| Chromium | As specified |
| Copper | As specified |
| Nickel | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM A106 Grade B.
ASTM A106 Gr B Coupling Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification and condition to be verified: ASTM A106 Grade B — condition per order.
Full chemistry, properties and equivalents are on the ASTM A106 Gr B grade page.
Other ASTM A106 Gr B pipe fittings
ASTM A106 Gr B Coupling — questions buyers ask
What is a half coupling used for?
It is welded onto a pipe or vessel to create a small threaded or socket-weld branch.
Can ASTM A106 Gr B couplings be welded to carbon steel?
Yes — matching carbon or low-alloy filler is used; joints to stainless need ER309L.
Which standard covers ASTM A106 Gr B couplings?
The material is ASTM A105; dimensions follow ASME B16.11. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a ASTM A106 Gr B coupling?
The steel price, the size and schedule or class, quantity, and the testing and documents required. Send your list and we quote the same working day.
What documents do you supply?
EN 10204 3.1 or 3.2 certificates available on request / as specified in the PO; dimensional reports as required. PMI can be arranged depending on product and requirements, as specified in the PO.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026