SS 347 Seamless PipeASTM A312 · ASME B36.19 · Manufacturer, stockist & exporter, India
AISI 347 · UNS S34700
An SS 347 seamless pipe is pipe made without a weld seam, by piercing and drawing, made from SS 347 to ASTM A312 TP347. Seamless pipe is the choice for high pressure, high temperature and critical service where a weld seam is not wanted.
- ASTM A312
- ASME B36.19
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is an SS 347 Seamless Pipe?
- What it is
- Pipe made without a weld seam, by piercing and drawing
- Material
- ASTM A312 TP347
- Dimensions
- ASME B36.19 · B36.10
- Grade
- SS 347 · UNS S34700
- Best at
- Welded high-temperature piping in refineries and power plants
SS 347 Seamless Pipe Specification
| Product | SS 347 Seamless Pipe |
|---|---|
| Material standard | ASTM A312 TP347 |
| Dimensional standard | ASME B36.19 · B36.10 |
| Sizes | NPS ⅛" – 24", Sch 5S – XXS |
| Length | Random, double random or cut lengths |
| Testing | PMI · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
When to Choose a Seamless Pipe
Seamless pipe is the choice for high pressure, high temperature and critical service where a weld seam is not wanted.
- No weld seam
- NPS ⅛" – 24"
- Schedules 5S – XXS
More on choosing: Seamless pipe guide.
SS 347 Seamless Pipe: Why 347 for seamless pipes
Seamless pipe is the choice for high pressure, high temperature and critical service where a weld seam is not wanted. In SS 347, 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 tubulars are the default for corrosive and hygienic service. SS 347 is picked for welded high-temperature piping in refineries and power plants. |
|---|---|
| Typical service | Refinery hydroprocessing — Reactor effluent piping and exchangers. |
| Welding to carbon steel | ER309L (or E309L electrode) is the usual filler when joining it to carbon steel |
| Matching filler | ER347 (AWS A5.9) |
SS 347 Seamless Pipe Chemical Composition
| Element | Weight % |
|---|---|
| Chromium | 17.0 – 19.0 |
| Nickel | 9.0 – 13.0 |
| Niobium | 10 × C min, 1.00 max |
| Carbon | 0.08 max |
| Manganese | 2.00 max |
| Silicon | 0.75 max |
| Phosphorus | 0.045 max |
| Sulphur | 0.030 max |
SS 347 Seamless Pipe Mechanical Properties
| Annealed plate & sheet | Value |
|---|---|
| Tensile strength | 515 MPa · 75 ksi |
| Yield strength 0.2% | 205 MPa · 30 ksi |
| Elongation | 40% |
| Hardness | 201 HB max |
Full chemistry, properties and equivalents are on the SS 347 grade page.
Other SS 347 pipes & tubes
SS 347 Seamless Pipes for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiSS 347 Seamless Pipe — questions buyers ask
Why choose seamless over welded pipe?
No longitudinal weld means uniform strength and corrosion resistance — preferred for pressure and critical service.
Can SS 347 seamless pipes be welded to carbon steel?
Yes — ER309L (or E309L electrode) is the usual filler when joining it to carbon steel.
Which standard covers SS 347 seamless pipes?
The material is ASTM A312 TP347; dimensions follow ASME B36.19 · B36.10. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a SS 347 seamless pipe?
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 mill certificates as standard, 3.2 with third-party inspection on request, plus dimensional and PMI reports.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026