Sihe Steel
Sihe Steel
Explore our diverse industrial steel range covering grades ASTM 430, 409, 316L, 304, and proprietary capillary innovations engineered for demanding physical architectures.
Established with a dedication to advancing global fluid control and structural tubing designs, Liaocheng Sihe Stainless Steel Material LTD operates from the manufacturing heart of China, running six highly optimized production lines. We specialize in producing elite Austenitic, Duplex, and Nickel Alloy structural materials. By strictly adhering to international production standards such as GB, ASTM, ASME, JIS, and EN, we supply global EPC contractors, semiconductor device fabricators, automotive giants, and petrochemical refineries with consistent, high-integrity piping systems.
Our infrastructure includes advanced, inline atmosphere-controlled bright annealing facilities that permit stress-free processing of continuous ultra-long coils. By mitigating surface oxidation and maintaining optimal thermodynamic controls, we guarantee high grain stability, precise mechanical properties, and excellent surface roughness values (Ra). This strict processing ensures resistance to pitting and localized crevice corrosion in seawater and harsh chemical environments.
Selecting the optimal alloy requires a meticulous understanding of chemical compositions, yield dynamics, and physical performance thresholds. Here we map our primary industrial options.
| Material Designation | UNS / EN Code | Main Chemical Profile (%) | Tensile Strength (MPa) | Yield Strength 0.2% (MPa) | Primary Industrial Utility |
|---|---|---|---|---|---|
| Austenitic 304/304L | UNS S30400 / S30403 | 18-20% Cr, 8-10.5% Ni, ≤0.03% C (L-grade) | ≥ 485 | ≥ 170 | General food manufacturing, chemical storage, precision components |
| Austenitic 316/316L | UNS S31600 / S31603 | 16-18% Cr, 10-14% Ni, 2-3% Mo | ≥ 485 | ≥ 170 | Marine piping, pharmaceutical biotech pipelines, subsea umbilicals |
| Duplex 2205 | UNS S32205 / S31803 | 22-23% Cr, 4.5-6.5% Ni, 3-3.5% Mo, 0.14-0.2% N | ≥ 655 | ≥ 450 | High chloride environments, offshore petrochemical structural components |
| Super Duplex 2507 | UNS S32750 | 24-26% Cr, 6-8% Ni, 3-5% Mo, 0.24-0.32% N | ≥ 750 | ≥ 550 | Deepwater oil exploration, desalination plants, pressure vessels |
| Incoloy 825 | UNS N08825 | 38-46% Ni, 19.5-23.5% Cr, 2.5-3.5% Cu, 1.5-3% Mo | ≥ 586 | ≥ 241 | Acid production systems, high-temperature sour oil gas extraction |
| Inconel 625 | UNS N06625 | ≥58% Ni, 20-23% Cr, 8-10% Mo, 3.15-4.15% Nb+Ta | ≥ 827 | ≥ 414 | Aerospace propulsion, deep sea marine equipment, waste processing |
Liaocheng Sihe provides stainless steel coiled tubing in an expansive dimensional matrix to suit custom deployment projects. Our seamless coiled tubing is available in outer diameters ranging from 0.125 inch (3.175 mm) to 1.0 inch (25.4 mm), with wall thicknesses reaching up to 0.165 inch (3.0 mm). To facilitate efficient manufacturing of subsea umbilicals and complex industrial heat exchangers, we can deliver single continuous lengths of up to 32,800 feet (10,000 meters) without orbital welds, drastically minimizing prospective leak paths and ensuring optimal pressure handling.
By using precision cold drawing methods combined with our bright annealing lines, we achieve highly accurate dimensional tolerances. This structural reliability prevents wall thinning and micro-fissuring, keeping mechanical performance stable even under intense high-pressure applications.
From subsea oil extraction to cleanrooms in semiconductor facilities, 304 and high-alloy stainless steels provide the essential structural and chemical stability required by modern industries.
As hydrocarbon extraction shifts into deeper water and harsher offshore settings, structural safety demands are high. Our continuous long coiled tubing (up to 10,000m) is ideal for subsea chemical injection and control systems. Utilizing alloys like Duplex 2205, Super Duplex 2507, and Incoloy 825 prevents stress corrosion cracking (SCC) caused by high pressures and corrosive seawater.
High-purity gas delivery in ultra-clean semiconductor processing requires inner surfaces that are free of particulate matter and chemical residues. Our precision-drawn, bright annealed 304 and 316L capillary tubes feature a smooth internal surface (low Ra roughness) that minimizes chemical entrapment and particle shed, ensuring contamination-free cleanroom environments.
Process equipment in the pharmaceutical sector must withstand frequent Clean-in-Place (CIP) and Sterilize-in-Place (SIP) cycles using aggressive sanitizers and superheated steam. Our electropolished and bright annealed 316L seamless pipes prevent biofilm formation and pit corrosion, meeting stringent FDA and ASME BPE sanitary criteria.
Heat transfer efficiency and thermal fatigue resistance are critical in high-temperature heat exchangers. The addition of titanium in stabilized grades like 321, along with the high molybdenum content in 317L, prevents chromium carbide precipitation during welding. This guarantees long-term durability and structural integrity under constant thermal cycling.
Aerospace hydraulic systems and fuel injection lines require lightweight, high-strength tubing capable of withstanding extreme vibration and pressure fluctuations. Our custom-fabricated seamless capillaries in Inconel 625 and high-strength austenitics deliver excellent fatigue limits and oxidation resistance at elevated temperatures.
Our coiled tubes (6.35mm to 19mm in diameter) are widely used in commercial condensers and industrial cooling lines. Excellent thermal conductivity, easy bending, and reliable wall thickness ensure worry-free refrigerant circulation under high pressures without leaking or fracturing.
Located in Liaocheng, China's central stainless steel manufacturing cluster, our facility benefits from local raw material sourcing, advanced metallurgy infrastructure, and highly efficient logistics networks. This proximity allows us to source premium hot-rolled and cold-rolled raw bands with minimal transport delays, reducing overall processing cycles.
Our facility runs continuous automated draw-benches and atmosphere-controlled induction furnaces to optimize energy use and output consistency. By managing all processing steps in-house—including drawing, bright annealing, cleaning, straightening, and testing—we maintain close control over production costs. This vertical integration allows us to pass savings on to our global partners without compromising product quality.
Additionally, our proximity to major international ports like Qingdao ensures reliable ocean shipping schedules. We coordinate closely with global shipping lines to offer steady delivery timelines, securing supply chains for large-scale construction, chemical plant upgrades, and manufacturing projects worldwide.
Every industry requires specific configurations. We offer advanced customization services to match your design blueprints and project tolerances.
We process a wide range of materials—including 304, 316L, 321, 2205, 2507, and Incoloy 825—with diameters from 6.35mm to 19mm. Custom dimensions are easily accommodated to meet specific project needs.
Our tooling workshop performs precise bending, tight-radius spiral forming, multi-pass drawing, and custom coiling. This specialized shaping prepares tubes for direct installation in high-density shell-and-tube heat exchangers.
We provide burr-free mechanical cutting, high-speed abrasive sawing, and non-contact laser cutting. This ensures precise length tolerances and clean, perpendicular end cuts for efficient orbital welding.
We offer tailored surface finishes, including acid pickling, passivation, and bright annealing. Electropolishing (EP) is also available to achieve the low micro-inch roughness values required for high-purity processes.
We perform precise end flanging, expansion, reducing, and flare profiling. These forms are commonly used in automotive exhaust systems, chemical pipelines, and instrument connections to ensure reliable joints.
Reliable performance under pressure requires strict, documented quality control. We perform comprehensive mechanical and non-destructive testing on every batch.
We test every production run to ensure compliance with global standards, including EN 10204 3.1 Mill Test Certificates (MTR), PED 2014/68/EU, and NACE MR0175/ISO 15156 for sour service applications. Our quality control team utilizes advanced testing equipment to verify mechanical properties, dimensions, and chemical composition:
Advancements in steel processing are essential for supporting clean energy transition projects and high-performance equipment manufacturing.
We are incorporating lower-emission melting practices and utilizing high-grade recycled alloy components. This focus on green manufacturing reduces carbon footprint metrics while keeping impurity levels like sulfur and phosphorus very low.
As hydrogen energy distribution expands, standard steels face risks from hydrogen embrittlement. We are researching grain orientation refinements and nickel-equivalent adjustments in our 316L and high-nickel alloys to ensure safe containment at high pressures.
We are integrating real-time laser gauge monitoring and computerized optical inspection along our drawing lines. This tracking helps optimize dimensional consistency and detect surface variations instantly.
Technical details, order structures, shipping parameters, and quality guarantees for our global customer base.
Complete your structural design pipeline with our high-alloy options, including Super Duplex 2507, 310S, 316, and specialized coiled lines.
