Sihe Steel
Sihe Steel
Explore our top industrial-grade steel sheets, plates, custom precision tubes, and specialized coiled systems engineered for harsh environments.
In modern global industrial piping networks, the demand for highly reliable structural materials is growing exponentially. Among the myriad alloys, 304L (UNS S30403 / EN 1.4307) stands out as the ultimate low-carbon variant of the standard 304 grade. Operating in harsh, demanding industrial ecosystems, standard 304 is often prone to carbide precipitation during welding procedures. The unique chemical architecture of 304L—limiting carbon to a maximum of 0.030%—mitigates this risk, thereby preventing intergranular corrosion in the heat-affected zone (HAZ).
This fundamental difference makes 304L seamless steel tubes indispensable for critical industries worldwide. The modern commercial status of 304L shows high demand across chemical processing plants, ocean exploration, semiconductor cleanrooms, and renewable energy sectors. As a key supplier, Liaocheng Sihe Stainless Steel Material Ltd. leverages decades of material expertise to provide high-purity, high-durability products to the domestic and international markets.
A granular look at the chemistry, physical attributes, and performance parameters that qualify 304L for critical B2B applications.
| Element/Parameter | Alloy 304 (UNS S30400) | Alloy 304L (UNS S30403) | Alloy 316L (UNS S31603) | Duplex 2205 (UNS S31803) |
|---|---|---|---|---|
| Carbon (C) max % | 0.080 | 0.030 | 0.030 | 0.030 |
| Chromium (Cr) % | 18.0 - 20.0 | 18.0 - 20.0 | 16.0 - 18.0 | 22.0 - 23.0 |
| Nickel (Ni) % | 8.0 - 10.5 | 8.0 - 12.0 | 10.0 - 14.0 | 4.5 - 6.5 |
| Molybdenum (Mo) % | - | - | 2.0 - 3.0 | 3.0 - 3.5 |
| Yield Strength (Mpa) min | 205 | 170 | 170 | 450 |
| Tensile Strength (Mpa) min | 515 | 485 | 485 | 620 |
| Elongation in 2" min % | 35 | 35 | 35 | 25 |
Continuous cold drawing guarantees high concentricity and low tolerance deviation down to ±0.05mm. Extremely critical for orbitally welded pipelines.
Hardness levels are carefully controlled below HRB 90 (Rockwell B scale) or HV 200 via localized heat treatments, facilitating smooth tube flanging.
With elongation parameters reaching up to 35%, our tubes adapt easily to bending, coiling, and complex structural configurations without cracking.
For over a decade, Liaocheng Sihe Stainless Steel Material LTD has set the gold standard in premium stainless steel tube manufacturing. Based in China, we run six state-of-the-art production lines designed for coiled tubes, precision tubes, polished tubing, and sheet fabrication. Our products are exported to over 30 countries and regions, including the United States, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe.
We operate in strict accordance with major global regulatory standards, including GB, ASTM, ASME, JIS, and EN. We specialize in working with a wide range of corrosion-resistant alloys, including:
Our coiled tubing solutions are available in outer diameters ranging from 0.125 inches (3.175 mm) to 1 inch (25.4 mm), with wall thicknesses up to 0.165 inches (3.0 mm). To minimize offshore leak risks and eliminate the need for orbital welds, we supply continuous coil lengths of up to 32,800 feet (10,000 meters).
Our manufacturing processes are certified to strict quality standards to ensure safety, reliability, and conformance to international specs.
How our 304L, 316L, and specialized duplex tubing systems perform in key industries around the globe.
High thermal transfer efficiency combined with exceptional fouling resistance makes our 304L tubes ideal for heat exchange modules in harsh chemical plants.
Corrosion-resistant coiled systems ensure safe handling of modern eco-refrigerants under high pressure, preventing refrigerant leaks.
Superior resistance to organic acids and reducing chemicals. Our 304L tubing helps prevent localized stress corrosion cracking in high-temperature environments.
Highly polished interior surfaces prevent bacterial contamination. Easily supports Clean-in-Place (CIP) regimes with aggressive cleaning solutions.
We supply ASTM A269 compliant capillary and precision tubing, offering high interior finish and dimensional accuracy for sanitary applications.
Our tubing withstands high-pressure superheated steam cycles, and resists oxidation in fossil-fuel and nuclear steam generators.
Specifically designed for subsea umbilical control systems, chemical injection lines, and processing systems exposed to sour gas environments.
Lightweight, high-strength tubing engineered for fuel lines, hydraulic controls, exhaust gas recirculation (EGR), and aerospace instrumentation.
Our state-of-the-art facility goes beyond simple extrusion. We offer complete customization, precision fabrication, and exhaustive testing protocols.
We process a wide range of materials, including 304, 316L, and Duplex 2205. Our tube diameters range from 6.35 mm to 19 mm, with custom processing options such as spiral bending, precision drawing, and custom sizing to fit your specific heat exchanger setup.
We utilize laser cutting, mechanical saws, and abrasive disc cutters to deliver exact tolerances. Post-cut straightening operations eliminate curvature, ensuring high concentricity for automated tube assembly systems.
Our services include mechanical polishing, pickling, and online bright annealing under a protective gas atmosphere. We also offer precision flanging processing to ensure strong joints in automotive exhaust systems and chemical pipelines.
To ensure reliable performance in deep subsea operations and high-pressure chemical reactions, we implement a multi-stage quality control process for every production run.
Procuring industrial materials at scale requires a balance of price stability, consistent quality, and reliable logistics. As global steel markets face changing tariffs, volatile nickel prices, and shifts in shipping networks, Liaocheng Sihe serves as a strategic sourcing partner.
By running dedicated raw material sourcing channels and three independent coiled tube production lines, we mitigate market price fluctuations. We offer flexible B2B agreements, including annual fixed-price options, safety stock programs, and custom logistics management.
Whether shipping to the Americas, Europe, or Asia, our export packaging protects the tubing from environmental wear. We use heavy-duty wooden crates, plastic end caps, and desiccant bags to prevent moisture buildup and ocean spray corrosion during long-distance transport.
Answers to common technical, metallurgical, and sourcing questions from engineers, buyers, and project managers.
Browse our full range of heat exchanger pipes, precision coiled lines, capillary tubing, and specialized stainless steel grades.
