Sihe Steel
Sihe Steel
Direct supply from state-of-the-art production lines conforming strictly to GB, ASTM, ASME, JIS, and EN standards.
Understanding the critical role of Type 316L Stainless Steel in demanding industrial ecosystems.
In modern industrial manufacturing, 316L stainless steel tubing (UNS S31603) stands as a cornerstone material. As a low-carbon derivative of the standard chromium-nickel-molybdenum austenitic alloy, 316L offers exceptional resistance to chloride-induced pitting, stress corrosion cracking, and intergranular carbide precipitation during welding. Globally, the demand for 316L tubes has surged, driven by the expansion of offshore oil extraction, chemical processing plants, high-purity biopharmaceutical systems, and renewable energy grids.
The addition of 2.0% to 3.0% molybdenum in 316L significantly improves the material's Pitting Resistance Equivalent Number (PREN), calculated as: PREN = %Cr + 3.3%Mo + 16%N. With a typical PREN range of 23 to 25, 316L provides a cost-effective, high-performance solution that bridges the gap between conventional 304/304L stainless steels and more costly nickel-base superalloys or duplex piping systems.
Understanding how 316L compares to standard austenitic steels and specialized duplex alloys is vital for chemical plant designers and pipeline engineers.
| Alloy Grade | UNS Designation | Major Chemical Elements (%) | Yield Strength (MPa) | PREN Value | Optimal Environment |
|---|---|---|---|---|---|
| 304 / 304L | S30400 / S30403 | 18Cr, 8Ni, Max 0.03C | ≥ 170 | 18 | Atmospheric, Freshwater |
| 316L | S31603 | 16-18Cr, 10-14Ni, 2-3Mo | ≥ 170 | 23-25 | Chloride, Marine, Pharmaceutical |
| Duplex 2205 | S32205 / S31803 | 22Cr, 5.5Ni, 3Mo, 0.18N | ≥ 450 | 35 | Deep-sea Oil, Chemical Process |
| Super Duplex 2507 | S32750 | 25Cr, 7Ni, 4Mo, 0.27N | ≥ 550 | 42 | High-Salinity Desalination |
| Incoloy 825 | N08825 | 38-46Ni, 19-23.5Cr, 2.5-3.5Cu | ≥ 240 | - | Highly Corrosive Sour Gas Wells |
Innovations in Bright Annealing, Green Steel, and Precision Manufacturing Systems.
Our production facilities utilize protective hydrogen atmosphere heat treatments. This online process removes oxide scales without traditional chemical pickling, yielding a smooth, mirror-like, and highly clean inside diameter (ID) and outside diameter (OD).
To support deepwater oil & gas umbilical production, we offer seamless and welded coiled tubing in continuous lengths of up to 10,000 meters (32,800 feet). This minimizes orbital field joints, dramatically reducing leak pathways.
Our Quality Management Systems (QMS) operate under ISO 9001 guidelines, executing 100% Non-Destructive Testing (NDT), including online eddy current scanning, hydrostatic pressure verification, and pneumatic integrity testing.
Where high-performance 316L tubing secures process pipelines and high-pressure fluid systems.
A global leader in high-performance stainless steel coiled tubing and precision alloys.
Liaocheng Sihe Stainless Steel Material LTD is a leading expert in the manufacturing and development of premium-grade stainless steel coiled tubes, stainless steel polishing tubes, and seamless coiled tubing. With a rich history of over ten years in production, we operate six advanced production lines, optimizing metallurgical processing to achieve outstanding tolerances and durability.
Our steel grades include 304/304L, 316L, 321, 317L, 309S, 310S, and specialty super alloys such as Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625. We strictly enforce international standards, including GB, ASTM, ASME, JIS, and EN, to guarantee safety in demanding operating environments.
Our coiled tubing is available in an outer diameter range of 0.125 inch (3.175 mm) to 1 inch (25.4 mm), with wall thicknesses up to 0.165 inch (3 mm). To minimize weld joint interfaces, we offer continuous lengths up to 32,800 feet (10,000 meters), enabling cost-effective subsea umbilical manufacturing.
Our modern plant includes state-of-the-art tooling for complex post-processing work:
Liaocheng Sihe has exported high-quality stainless steel materials to over 30 countries and regions worldwide, including the United States, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe. Over 80% of our production is exported globally, meeting strict quality audits.
Explore our main product lines designed to meet demanding industrial and commercial requirements.
Duplex and austenitic alloy coils designed for downhole oil extractions and petrochemical process tubes.
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Standard 1/2-inch outer diameter coiled tubing systems for control fluid lines and subsea manifolds.
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High-temperature stainless steel tubing systems resistant to oxidation and scaling up to 1100°C.
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Common questions from engineering buyers, procurement officers, and piping designers.
High-precision tubes, plates, and fittings available for global procurement.
