Sihe Steel
Sihe Steel
Explore our elite range of corrosion-resistant, high-durability stainless solutions
ASTM 304 (UNS S30400) remains the cornerstone of modern industrial fluid control, structural engineering, and process manufacturing worldwide. Its balanced alloy chemistry—incorporating a minimum of 18% chromium and 8% nickel—imparts exceptional corrosion resistance, high tensile strength, and excellent formability. Across the Americas, Europe, and the Asia-Pacific region, the demand for ASTM 304 stainless steel pipes is expanding rapidly. This growth is driven by the modernization of municipal water infrastructure, the rise of high-purity semiconductor fabs, and transition phases in biochemical processing units.
As deepwater exploration pushes into harsher oceanic basins, subsea control units require incredibly reliable, continuous, long-length pipelines. Seamless coiled tubing, specifically manufactured under stringent ASTM standards, removes high-risk mechanical joints. This optimizes flow velocity and prevents critical leaks under thousands of pounds of hydrostatic pressure. Liaocheng Sihe Stainless Steel Material LTD has established itself as an engineering pioneer, transforming raw metallurgical compositions into world-class, ultra-long coiled tubing and high-precision capillary networks that operate under the most challenging physical parameters.
"The demand for high-integrity seamless configurations has risen by 14% globally over the last three fiscal quarters. Industrial pipelines are no longer viewed as simple conduits; they are engineered systems requiring precise chemical tolerances, low delta-ferrite content, and exceptionally smooth inner surfaces to mitigate boundary-layer drag and bacterial colonization."
— Global Metallurgical & Piping Infrastructure Review, 2024The performance of ASTM 304 and 304L is dictated by their austenitic microstructure. ASTM 304L contains lower carbon limits (maximum 0.030% compared to 0.08% in standard 304). This low carbon design prevents sensitization—the precipitation of chromium carbides at grain boundaries during welding. This effectively mitigates intergranular corrosion (IGC) near heat-affected zones (HAZ). For high-temperature setups or petrochemical refinement, maintaining this low carbon ratio ensures optimal mechanical integrity and thermal stability up to 800°C.
Additionally, we supply higher alloy specifications, including 316L, 321, 317L, 309S, 310S, and nickel-base alloys like Incoloy 800/825 and Inconel 625. These alloys are ideal for environments containing high chloride concentrations, sour gas (H2S), or severe thermal stress. The table below lists the mechanical and chemical parameters we adhere to in our manufacturing lines.
| Grade Designation | UNS Number | Cr (Chromium) % | Ni (Nickel) % | C (Carbon) Max % | Tensile Strength (MPa) | Yield Strength (MPa) |
|---|---|---|---|---|---|---|
| ASTM 304 | S30400 | 18.0 - 20.0 | 8.0 - 10.5 | 0.08 | ≥ 515 | ≥ 205 |
| ASTM 304L | S30403 | 18.0 - 20.0 | 8.0 - 12.0 | 0.03 | ≥ 485 | ≥ 170 |
| ASTM 316L | S31603 | 16.0 - 18.0 | 10.0 - 14.0 | 0.03 | ≥ 485 | ≥ 170 |
| Duplex 2205 | S32205 | 22.0 - 23.0 | 4.5 - 6.5 | 0.03 | ≥ 655 | ≥ 450 |
| Super Duplex 2507 | S32750 | 24.0 - 26.0 | 6.0 - 8.0 | 0.03 | ≥ 800 | ≥ 550 |
| Incoloy 825 | N08825 | 19.5 - 23.5 | 38.0 - 46.0 | 0.05 | ≥ 586 | ≥ 241 |
Liaocheng Sihe Stainless Steel Material LTD runs six advanced, high-capacity production lines. These lines incorporate several technical milestones that set us apart from traditional manufacturers:
Our online bright annealing technology operates under a controlled hydrogen-nitrogen atmosphere. This prevents surface oxidation and decarburization, producing a highly reflective, ultra-smooth inner and outer surface finish. This process also improves corrosion resistance without requiring post-heat pickling.
We manufacture continuous, weld-free coiled tubing in single-run lengths of up to 32,800 feet (10,000 meters). These long lengths reduce the need for orbital orbital welds and mechanical fittings during installation, significantly lowering the risk of joint failure in subsea control lines.
Quality control is integrated into every step of our process. Each pipe batch undergoes a series of mandatory tests, including hydrostatic testing, pneumatic pressure testing, hardness testing, flaring and flattening tests, tensile strength testing, and 100% electromagnetic eddy current inspections.
Our stainless steel tubes are engineered to meet the strict demands of several highly regulated industries:
Sihe Steel provides custom fabrication and precision processing services to deliver install-ready piping components directly to your job site:
We work with a wide range of materials (including 304, 316L, 2205) and custom specifications, covering tube diameters from 6.35mm to 19mm for coiled runs.
Our facility offers precision bending, spiral forming, coiling, and precision drawing, producing custom shapes designed specifically for heat exchangers.
We provide high-precision, low-tolerance sizing using advanced laser cutting, clean mechanical cutting, and flame cutting technologies.
We offer specialized surface treatments, including electro-polishing (EP) and mechanical polishing, to meet high-purity fluid transfer standards.
Our custom flanging services provide reliable, leak-free end connections for automotive exhaust networks, chemical lines, and precision instruments.
Verified compliance to global standards for high-pressure and critical applications
Technical specifications, order processing, and delivery information
High-quality welded tubing, plates, and heat exchanger components
