Electropolished 316L Stainless Steel Precision EP Pipe for Semiconductor Applications
Electropolished 316L Stainless Steel Precision EP Pipe for Semiconductor (UHP) Systems
Material
This product is a precision stainless steel pipe/tubing made from 316L austenitic stainless steel (low-carbon, Mo-alloyed) and finished by electropolishing (EP)—primarily on the internal wetted surface—to achieve an ultra-smooth, contamination-resistant surface for semiconductor high-purity and ultra-high-purity (HP/UHP) gas and chemical delivery lines.
Specifications
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Grade: 316L (UNS S31603 / EN 1.4404)
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Manufacturing: Seamless or welded + cold worked (per project requirement); solution annealed / bright annealed available (typical for precision tubing)
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Size range (typical): small-to-medium OD precision tubing/pipe; cut-to-length and coil/straight lengths available (per order)
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Surface finish (ID, typical UHP requirement): Electropolished Ra ≤ 10 μin (0.25 μm); finer finishes may be available by agreement
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Cleanliness & packaging: cleaned, capped, and packaged to reduce re-contamination risk for UHP service
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Documentation (typical): MTR/CMTR, heat & lot traceability, CoC, and optional roughness test report (profilometer) per purchase order
Key Features
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Ultra-smooth wetted surface after EP for reduced particle adhesion and easier purge/cleaning
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Enhanced corrosion resistance through a cleaner, more uniform passive surface layer (EP + passivation when specified)
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Optimized for orbital welding and UHP fittings thanks to stable austenitic structure and consistent dimensional control (precision tubing practice)
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Low-carbon 316L chemistry helps minimize sensitization risk and supports welded assemblies in corrosive media
Our Advantages
1) “Will the ID surface finish really meet UHP expectations?”
Yes. We supply EP tubing with Ra targets aligned to common UHP practice (e.g., 10 μin / 0.25 μm max), and we can provide surface-roughness records when required.
2) “How do you control particles and re-contamination during shipping?”
We implement UHP cleaning and packaging practices (end-capping, protective bagging, controlled handling) to help keep the wetted surface clean from factory to installation.
3) “Is the material suitable for semiconductor chemical/gas distribution expectations?”
Semiconductor distribution systems commonly reference SEMI surface-condition concepts for wetted surfaces and stainless components used in chemical (gas/liquid) distribution in fabs. We can align supply to those requirements when specified.
4) “Do you offer chemistry options that improve weld quality and corrosion performance?”
For UHP systems, chemistry details (including low carbon and, when requested, controlled sulfur ranges) are often used to balance corrosion resistance with welding/processing performance. We can quote and supply accordingly with heat-level traceability.
5) “Can you prove compliance?”
We support full traceability (heat number → MTR), and can provide EN 10204 3.1 style documentation, plus optional inspection items (roughness, dimensional inspection, PMI) per PO.
Chemical Composition
| Grade (Common Name) | EN No. | C (max) | Si (max) | Mn (max) | P (max) | S (max) | Cr | Ni | Mo | N (max) | Ti / Nb (stabilizer) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 316L (UNS S31603) | 1.4404 | 0.030 | 1.00 | 2.00 | 0.045 | 0.015 | 16.5–18.5 | 10.0–13.0 | 2.00–2.50 | 0.11 | — |
| 304L (UNS S30403) | 1.4307 | 0.030 | 1.00 | 2.00 | 0.045 | 0.015 | 17.5–19.5 | 8.0–10.5 | — | 0.11 | — |
| 317L (UNS S31700) | 1.4438 | 0.030 | 1.00 | 2.00 | 0.045 | 0.015 | 17.5–19.5 | 13.0–16.0 | 3.00–4.00 | 0.11 | — |
| 321 (UNS S32100) | 1.4541 | 0.08 | 1.00 | 2.00 | 0.045 | 0.015 | 17.0–19.0 | 9.0–12.0 | — | — | Ti ≤ 5×C |
| 347 (UNS S34700) | 1.4550 | 0.08 | 1.00 | 2.00 | 0.045 | 0.015 | 17.0–19.0 | 9.0–12.0 | — | — | Nb (Cb) ≥ 10×C |
Mechanical Properties
| Grade | EN No. | 0.2% Proof / Yield Rp0.2 (MPa, min) | Tensile Rm (MPa) | Elongation A5 (min) |
|---|---|---|---|---|
| 316L | 1.4404 | 200 | 500–700 | 40 / 30 |
| 304L | 1.4307 | 175 | 500–700 | 45 / 35 |
| 317L | 1.4438 | 200 | 500–700 | 40 / 30 |
| 321 | 1.4541 | 190 | 500–700 | 40 / 30 |
| 347 | 1.4550 | 205 | 510–740 | 40 / 30 |
Applicable Standards
ASTM / ASME (typical references): ASTM A269/A269M, ASTM A270, ASTM A312, ASTM A967
SEMI (typical references): SEMI F19, SEMI F37
EN (typical references): EN 10088 series, EN 10216-5, EN 10296-2
JIS (typical reference): JIS G3459
GB (typical references): GB/T 14976, GB/T 12771, GB/T 13296
GOST (typical references): GOST 9941, GOST 9940
Application Areas
Primary field: Semiconductor manufacturing (HP/UHP utilities and process distribution).
Typical uses include:
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UHP specialty gas lines (distribution headers, tool hook-up, purge lines)
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High-purity chemical delivery (wet benches, chemical distribution panels, point-of-use feeds)
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DI water and process utility loops where surface cleanliness helps reduce contamination risk
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Slurry and process fluid transfer where smooth wetted surfaces help with cleanability and stability
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Interconnects to valves/fittings in gas cabinets, valve manifold boxes (VMB), and sub-fab distribution


Q: Are you trading company or manufacturer ?
A: manufacturer,also can do trading.
Q: How long is your delivery time?
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,
it is according to quantity.
Q: Do you provide samples? is it free or extra ?
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
Q: What is your terms of payment ?
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.
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