SS 904L Stub EndASTM A403 · ASME B16.9 · Manufacturer, trader & exporter, India
Alloy 904L · UNS N08904
An SS 904L stub end is a short pipe length with a flared lap that works with a lap joint flange, made from SS 904L to ASTM A403 WP904L. Stub ends are welded to the pipe and backed by a loose lap joint flange. Type A (long pattern, ASME B16.9) and short-pattern MSS SP-43 stub ends are the common choices.
For the full 904L fittings range, see SS 904L pipe fittings.
- ASTM A403
- ASME B16.9
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an SS 904L Stub End?
- What it is
- A short pipe length with a flared lap that works with a lap joint flange
- Material
- ASTM A403 WP904L
- Dimensions
- ASME B16.9 · MSS SP-43
- Grade
- SS 904L · UNS N08904
- Best at
- Dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water
SS 904L Stub End Specification
| Product | SS 904L Stub End |
|---|---|
| Material standard | ASTM A403 WP904L |
| Dimensional standard | ASME B16.9 · MSS SP-43 |
| Sizes | ½" – 48" |
| Wall / class | Sch 5S – XXS, to match pipe |
| Ends | Bevelled to ASME B16.25 |
| Testing | PMI (as specified in the PO) · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 or 3.2 on request / as specified in the PO |
When to Choose a Stub End
Stub ends are welded to the pipe and backed by a loose lap joint flange. Type A (long pattern, ASME B16.9) and short-pattern MSS SP-43 stub ends are the common choices.
- Long pattern (ASME B16.9) and short pattern (MSS SP-43)
- Type A, B and C lap designs
- Used with a carbon-steel backing flange to save alloy
More on choosing: Stub end guide.
SS 904L Stub End: Why 904L for stub ends
Stub ends are welded to the pipe and backed by a loose lap joint flange. Type A (long pattern, ASME B16.9) and short-pattern MSS SP-43 stub ends are the common choices. In SS 904L, 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 | Stainless fittings keep the line clean and corrosion-free. SS 904L is picked for dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water. |
|---|---|
| Typical service | Sulphuric acid plants — Coolers, piping and tanks for dilute sulphuric acid. |
| Welding to carbon steel | ER309L (or E309L electrode) is the usual filler when joining it to carbon steel |
| Matching filler | ER385 (AWS A5.9) |
SS 904L Stub End Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Nickel | As specified |
| Chromium | As specified |
| Molybdenum | As specified |
| Copper | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Nitrogen | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM A240 for UNS N08904.
SS 904L Stub End Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
| Hardness | 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 A240 for UNS N08904 — Annealed plate & sheet.
Full chemistry, properties and equivalents are on the SS 904L grade page.
Other SS 904L pipe fittings
SS 904L Stub End — questions buyers ask
Long or short stub end?
Long-pattern stub ends to ASME B16.9 suit most piping; short-pattern MSS SP-43 stub ends save alloy and space in low-pressure lines.
Can SS 904L stub ends be welded to carbon steel?
Yes — ER309L (or E309L electrode) is the usual filler when joining it to carbon steel.
Which standard covers SS 904L stub ends?
The material is ASTM A403 WP904L; dimensions follow ASME B16.9 · MSS SP-43. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a SS 904L stub end?
The alloy 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