Sihe Steel
Sihe Steel
Precision-drawn and polished metallic systems optimized for critical environments.
Liaocheng sihe stainless steel material LTD is a premier manufacturer based in China, boasting 10 years of specialized manufacturing history and operating six cutting-edge production lines. We are a leading expert in the development and manufacture of high-quality stainless steel coiled tubes, stainless steel polishing tubes, and seamless coiled tubing. Under strict compliance with domestic and international standards including GB, ASTM, ASME, JIS, and EN, we verify that every production batch matches strict structural tolerances.
Our material database spans standard austenitic grades to complex alloys: 304/304L, 316L, 321, 317L, 309S, 310S, and INCOLOY 800, alongside specialized alloys such as Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625. We serve critical industries including military systems, semiconductor fabrication, biopharma, precision instrumentation, marine umbilical networks, and chemical plants.
Our engineering capabilities allow us to customize dimensions to fit precise operational environments. Our coiled tubing is available in outer diameters (OD) ranging from 0.125 inch (3.175 mm) to 1 inch (25.4 mm), with wall thicknesses reaching up to 0.165 inch (3 mm). To facilitate efficient subsea and structural umbilical layouts, we supply continuous, orbit-weld-free single lengths up to 32,800 feet (10,000 meters).
Integrated processing capabilities include online bright annealing, precision drawing, localized bending, concentric flanging, and clean-room cleaning. These capabilities enable us to deliver reliable piping components directly to offshore platforms and industrial sites worldwide.
Understanding the raw material, technology, and cost dynamics that give Chinese fabricators global competence.
Chinese steel mills operate integrated supply networks, drawing on domestic and regional nickel and molybdenum reserves. By sourcing hot-rolled mother tubes directly from major smelters, Liaocheng Sihe coordinates chemical properties, ensuring molybdenum levels stay consistently within the 2.0-3.0% range required for pitting corrosion resistance in high-chloride marine environments.
To prevent Chromium depletion and scaling, our production lines utilize high-vacuum hydrogen-atmosphere bright annealing furnace systems. This treatment operates online at temperatures between 1040°C and 1150°C, restoring ductility and providing a clean, bright surface without structural carburization or oxidation.
Quality control relies on integrated non-destructive testing (NDT) steps. Every pipe section undergoes hydrostatic testing, continuous eddy current testing (ECT) per ASTM E426, ultrasonic inspections to check wall uniformity, and 100% pneumatic leak checks to assure reliable performance in high-pressure installations.
Where 316L and specialized high-alloy seamless pipes deliver critical reliability.
In deep offshore and harsh marine environments, oil and gas extractions demand reliable corrosion-resistant materials for coiled umbilical tubing. Our continuous long-length coiled tubes improve safety and operational reliability by eliminating orbital welds, which are potential failure points in high-pressure and high-vibration applications. Our products support critical subsea injection lines, hydraulic control loops, chemical dosing, and downhole instrumentation cables globally.
Engineering values, tolerances, and processing compliance for global project sourcing.
| Steel Grade Classification | Standards Compliance | Main Chemical Elements (%) | Primary Industrial Solutions |
|---|---|---|---|
| Austenitic 316L (UNS S31603) | ASTM A312, A269, A213, EN 10216-5 | Cr: 16-18, Ni: 10-14, Mo: 2.0-3.0, C ≤ 0.03 | Chloride-rich processes, marine equipment, pharmaceutical piping, heat exchangers. |
| Austenitic 304L (UNS S30403) | ASTM A312, A269, JIS G3459 | Cr: 18-20, Ni: 8-12, C ≤ 0.03 | General food processing, refrigeration loops, HVAC, low-corrosion process lines. |
| Duplex 2205 (UNS S31803 / S32205) | ASTM A789, A790 | Cr: 21-23, Ni: 4.5-6.5, Mo: 2.5-3.5, N: 0.08-0.2 | High strength, high pressure, localized stress corrosion cracking prevention. |
| Incoloy 825 (UNS N08825) | ASTM B163, B423 | Ni: 38-46, Fe: Bal, Cr: 19.5-23.5, Mo: 2.5-3.5 | Acid service pipelines, oil & gas production wells containing hydrogen sulfide. |
| Inconel 625 (UNS N06625) | ASTM B444, B704 | Ni ≥ 58, Cr: 20-23, Mo: 8-10, Nb + Ta: 3.15-4.15 | Extreme temperature processing, aerospace engine exhaust, subsea wellheads. |
Liaocheng Sihe maintains ISO and high-pressure system qualifications, assuring material traceability and conformance.
Developing customized piping solutions with modern manufacturing technologies.
We work with various materials (such as 304, 316L, and 2205) and custom specifications, covering diameters from 6.35 mm to 19 mm for stainless steel coils to match specific operating conditions.
Our workshop handles custom bending, spiral forming, and precision drawing, producing custom shapes for industrial heat exchangers and heating elements.
We offer laser cutting, mechanical cutting, and flame cutting options, delivering clean, burr-free end prep for high-tolerance piping assemblies.
We apply pickling and passivation, mechanical polishing, and electro-polishing (EP) processes to meet the interior cleanliness requirements of semi-conductor and biopharma facilities.
Our end-flanging processes are configured for automotive exhaust assemblies, chemical delivery pipelines, and precision instrumentation connectors, ensuring reliable joints.
Detailed answers about logistics, specifications, material grades, and payment procedures.
Browse our global product catalog for additional materials and alloy grades.
