SS 904L U-boltUNS N08904 · MSS SP-58 / manufacturer standard · Manufacturer, trader & exporter, India
Alloy 904L · UNS N08904
An SS 904L u-bolt is a U-shaped bolt for clamping pipes to supports. Finished fastener specification not asserted; material/feedstock may be supplied to ASTM A479 (UNS N08904), where applicable; manufacturing route and finished fastener requirements are to the purchase specification or project drawing. U-bolts hold pipes to supports and structures. Sized by pipe NPS with a threaded length on each leg.
See the SS 904L fasteners grade form page for standards and sizes.
- UNS N08904
- MSS SP-58 / manufacturer standard
- 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 U-bolt?
- What it is
- A U-shaped bolt for clamping pipes to supports
- Finished spec
- Not asserted
- Material / feedstock
- ASTM A479 (UNS N08904), where applicable
- Dimensions
- MSS SP-58 / manufacturer standard
- Grade
- SS 904L · UNS N08904
- Best at
- Dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water
SS 904L U-bolt Specification
| Product | SS 904L U-bolt |
|---|---|
| Finished fastener specification | Not asserted |
| Material / feedstock specification | ASTM A479 (UNS N08904), where applicable |
| Dimensional standard | MSS SP-58 / manufacturer standard |
| Manufacturing route | Route dependent on product design and purchase specification |
| Project / purchase specification | Yes — finished fastener requirements are to the purchase specification or project drawing |
| Sizes | M10 – M64 · ½" – 4" (others on request) |
| Threads | UNC · UN-8 · metric coarse |
| 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 an U-bolt
U-bolts hold pipes to supports and structures. Sized by pipe NPS with a threaded length on each leg.
- Sized to pipe NPS
- With nuts and plates
- Matching or isolated material
More on choosing: U-bolt guide.
SS 904L U-bolt: Why 904L for u-bolts
U-bolts hold pipes to supports and structures. Sized by pipe NPS with a threaded length on each leg. 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 fasteners resist atmospheric and process corrosion. 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. |
| Bolting | as the project specifies |
SS 904L U-bolt 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 U-bolt 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.
Standards on this page
Other SS 904L fasteners
SS 904L U-bolt — questions buyers ask
Should U-bolts match the pipe material?
Use the same alloy, or an isolating sleeve, to avoid galvanic corrosion between pipe and bolt.
What nut is used with SS 904L u-bolts?
Usually a nut in the same alloy — it may be machined from ASTM A479 bar, where applicable; finished requirements are to the purchase specification or project drawing.
Which standard covers SS 904L u-bolts?
Finished fastener specification: Not asserted. Material / feedstock: ASTM A479 (UNS N08904), where applicable. Dimensions: MSS SP-58 / manufacturer standard. State the finished specification, material and dimensions on your purchase order or project drawing.
What decides the price of a SS 904L u-bolt?
The alloy price, the size and dimensions, 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