Sihe Steel
Sihe Steel
Featuring advanced metallurgy and ultra-smooth inner-diameter finishes for safety-critical and high-purity industries.
Why mechanical polish, electropolishing (EP), and bright annealing (BA) define the safety boundary in modern high-purity processing.
Reducing internal surface roughness (Ra) down to < 0.13 μm eliminates microscopic pits where bacteria or process residues might gather. Our high-precision polishing processes yield ultra-clean, uniform, passivated inner boundaries that resist pitting corrosion.
Utilizing high-grade alloys such as 316L, Duplex 2205, Super Duplex 2507, and Inconel 625 ensures optimal resistance to Stress Corrosion Cracking (SCC) and localized crevice degradation, meeting strict parameters for severe offshore environments.
Our online bright annealing technology, conducted in a controlled reducing gas atmosphere (such as pure hydrogen), retains the metallurgical softness and smooth properties of stainless steel without generating heavy oxides, eliminating the need for post-annealing pickling.
A premier manufacturer delivering custom structural solutions, coiled umbilical tubing, and polished tubes worldwide.
Liaocheng Sihe Stainless Steel Material LTD stands as an engineering leader in China, operating six advanced production lines dedicated to manufacturing premium coiled tubing, capillary tubing, and high-performance polished pipes. Our facility integrates professional forming, drawing, and finish-polishing technologies to meet strict industrial demands.
We comply closely with global specifications, including GB, ASTM, ASME, JIS, and EN standards. Our alloy capabilities span standard 304/304L and 316L grades, high-temperature 321, 317L, 309S, and 310S, duplex alloys like 2205 and 2507, and advanced superalloys such as Incoloy 800, Incoloy 825, and Inconel 625.
Our coiled tubing portfolio offers seamless solutions ranging from an outer diameter of 0.125 inches (3.175 mm) up to 1 inch (25.4 mm), with wall thicknesses up to 0.165 inches (3 mm). To facilitate efficient umbilical manufacturing and subsea installation, we supply continuous coil lengths up to 32,800 feet (10,000 meters).
Supporting safety-critical networks, heat recovery equipment, and high-purity fluid transportation.
Continuous long coiled tubing is vital for control and chemical injection lines in subsea offshore extraction, where high resistance to high-pressure marine environments is essential.
Semiconductor fabrication plants utilize our electropolished and bright annealed tubing (Ra < 0.25 μm) to transport ultra-pure process gases without contamination.
Biotechnology, food processing, and pharmaceuticals require polished tubing to meet hygiene requirements, preventing media accumulation and simplified CIP/SIP cycles.
Continuous coiled lengths eliminate orbital weld joints, lowering leak risks and improving heat transfer efficiency in chemical processing plants.
Expanding structural utility through expert secondary operations and validation procedures.
We process various materials (such as 304, 316L, 2205) and custom specifications, covering diameters from 6.35 mm to 19 mm, tailored to specific process blueprints.
Advanced processing methods enable tight-tolerance helical loops, coiling, and custom configurations for dense spatial integration inside heat exchangers.
Utilizing laser, mechanical, or flame cutting tools ensures clean edges, minimal burrs, and high precision for automated orbital welding.
Our surface finishing services include mechanical polishing, pickling, and bright annealing to achieve target roughness requirements.
High-quality flanging provides reliable mechanical connections in automotive exhaust systems, chemical pipelines, and instrument lines.
Explore our core manufacturing categories, including coiled configurations, capillary lines, and sheets.
Engineered to support critical instrumentation, heat transfer systems, and chemical processing plants.
A comparative overview of our metallurgical solutions, dimensional limits, and mechanical standards.
| Material Class | Common Alloy Grades | Standards | OD Range | Main Characteristics |
|---|---|---|---|---|
| Austenitic Steel | 304/304L, 316/316L, 321, 317L, 309S, 310S | ASTM A269, A213, EN 10216-5, JIS G3459 | 3.175mm – 25.4mm | Ductility, clean surface passivation, excellent cryogenic toughness. |
| Duplex & Super Duplex | UNS S31803 (2205), UNS S32750 (2507) | ASTM A789, A790 | 6.0mm – 25.4mm | High mechanical strength, resistance to pitting in chloride/seawater. |
| Nickel Superalloy | Inconel 625 (UNS N06625), Incoloy 825 (N08825), 800 | ASTM B163, B423, B444 | 3.175mm – 19.05mm | Excellent resistance to high temperatures, high organic acid, and mineral acid corrosion. |
| Ferritic Steel | 409 (EN 1.4512) | EN 10088-2, ASTM A240 | Custom sizes available | Cost-effective structural utility, suitable for high-temperature automotive exhaust systems. |
To ensure high quality in demanding environments, we utilize rigorous testing procedures. This includes hydrostatic, pneumatic, tensile, and hardness validation (100%), alongside expansion, flaring, compression, and bend testing to confirm structural reliability.
Fully certified processes, raw material traceability, and international standards verification.
Liaocheng Sihe is committed to transparency and product quality. Every shipment includes comprehensive chemical analysis, mechanical property verification, and non-destructive testing reports. Our production processes conform to international standard criteria, including ISO 9001 and pressure equipment certifications.
Crucial details regarding ordering terms, quality verification, packaging, and shipping processes.
Explore our technical piping catalog, designed to meet rigorous standards for high-temperature and structural applications.
