Sihe Steel
Sihe Steel
Engineered for extreme thermal cycles and high-pressure chemical environments. Explore our structural configurations.
Liaocheng Sihe Stainless Steel Material LTD is a premier manufacturer in China specializing in the design, development, and supply of high-performance stainless steel coiled tubes, precision polishing tubes, and seamless coiled tubing networks. Equipped with six state-of-the-art production lines, our industrial facilities strictly adhere to rigorous quality benchmarks including GB, ASTM, ASME, JIS, and EN standards.
Our commitment is centered on delivering superior metallurgical structural integrity. We produce tubing across highly sought-after material grades, including Austenitic Stainless Steels 304/304L, 316L, 321, 317L, 309S, and 310S, as well as highly specialized alloys like Incoloy 800, Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625.
Through our online bright annealing technology and specialized processing services—which range from multi-angle bending, spiral forming, and precision drawing to high-speed laser cutting and end flanging—we ensure that every meter of tubing matches the dynamic requirements of offshore umbilicals, petrochemical heat exchangers, semiconductor pipelines, and aerospace structures.
Under high-temperature and aggressive chloride conditions, selecting the right alloy defines the operational lifespan of your mechanical systems.
In modern industrial process engineering, thermal equipment efficiency is tightly bound to the mechanical integrity of the tubes. The global trend is shifting away from traditional carbon steels toward low-carbon molybdenum-stabilized alloys and duplex structures. This shift is driven by the demand for higher temperatures, increased flow rates, and resistance to aggressive cleaning cycles.
316L stainless steel contains a low carbon content (maximum 0.03%) which prevents chromium carbide precipitation at grain boundaries during welding processes. This feature eliminates intergranular corrosion risks. The crucial addition of 2.0% to 3.0% Molybdenum drastically improves the alloy's resistance to pitting and crevice corrosion in chloride-bearing solutions compared to standard 304 grade. This makes it the standard specification for marine coolers, food processing, and chemical handling.
When operating parameters exceed the limitations of 316L—particularly in high chloride offshore environments or critical chemical reactors—design engineers turn to high-alloy alternatives:
| Alloy Grade | UNS Designation | PREN (approx.) | Tensile Strength (MPa) | Yield Strength (0.2% MPa) | Primary Industrial Use Case |
|---|---|---|---|---|---|
| 304L | UNS S30403 | 18.0 | ≥ 485 | ≥ 170 | Mild chemical storage, beverage processing, general HVAC |
| 316L | UNS S31603 | 24.0 | ≥ 485 | ≥ 170 | Shell and tube heat exchangers, marine condensers, pharmaceutical bioreactors |
| Duplex 2205 | UNS S32205 | 35.0 | ≥ 655 | ≥ 450 | Offshore oil and gas pipelines, chemical tankers, seawater processing |
| Super Duplex 2507 | UNS S32750 | 42.0 | ≥ 800 | ≥ 550 | Flue-gas desulfurization, marine desalination, high salinity processing |
| Incoloy 825 | UNS N08825 | 31.0 | ≥ 585 | ≥ 240 | Souring oil gas wells, sulfuric acid manufacturing, nuclear fuel processing |
Mitigating high-risk variables for oil, gas, and energy transition projects.
As gas and oil exploration ventures move deeper into marine depths, structural equipment must survive intense hydro-pressure. We supply ultra-long continuous coiled tubes up to 10,000 meters (32,800 feet) in a single weld-free line, ideal for deep-ocean subsea control umbilicals.
We provide full materials transparency. Each batch leaves our plant certified with complete Mill Test Certificates (MTC) conforming to EN 10204 3.1. All chemical analysis and mechanical testing reports are fully traceable.
Using reinforced structural spools, specialized hazard-packing, and heavy-duty steel skeleton drums, we prevent transit damage, ovality deformation, and chemical corrosion during long marine transports to the Americas, Europe, and Asia.
We configure coiled piping directly to structural layouts, minimizing mechanical failure points for final assemblers.
We work within specialized dimensional limits. Coiled tubing outer diameters arrange from 0.125 inches (3.175mm) to 1.0 inch (25.4mm) with wall thicknesses up to 0.165 inches (3.0mm). We also build custom outer and inner diameter tolerances matching high-precision micro-instrument setups.
Through our dedicated forming division, we execute complex custom geometric shapes: multi-axis structural bending, tight spiral heat exchanger wraps, precision redraws, and pre-flanged piping configurations ready for direct chemical integration.
We operate advanced physical processing blocks: high-accuracy multi-axis CNC laser cutting, clean mechanical cutting, and flame profiling. This ensures clean, burr-free perpendicular end-cuts ready for immediate orbital welding.
Delivering high thermal efficiency and anti-corrosive security across critical global industries.
High-efficiency heat exchangers require smooth internal walls to maximize fluid turbulence while preventing scaling and thermal resistance buildup.
Optimized for phase-change thermodynamic stability, our coiled systems maintain structural integrity under continuous pressure fluctuations.
Engineered to handle hot organic solvents, acidic fluids, and caustic solutions without localized pitting or mechanical wall degradation.
Constructed with smooth, electropolished inner dimensions (EP) that prevent bacterial attachment and meet strict FDA-regulated hygiene standards.
Our TP316L high-purity tubing ensures clean liquid transport with minimal trace-metal contamination in biotech and pharmaceutical synthesis loops.
Supplying boiler superheaters, condensers, and thermal transfer lines with stable, high-pressure steam handling up to supercritical conditions.
Corrosion-resistant structures engineered for sour oil environments containing H2S, preventing sulfide stress cracking (SSC) in active lines.
Precision-made hydraulic fluid and high-pressure fuel lines designed to withstand severe vibrations and high G-force environments.
Every millimeter is tested to guarantee structural reliability in critical systems.
Liaocheng Sihe is equipped with an advanced online bright annealing system. Unlike conventional heat treatment methods that leave surface scales requiring pickling, bright annealing operates under a controlled atmosphere of pure hydrogen/nitrogen. This process relieves manufacturing stresses, softens the stainless steel, and retains a clean, mirror-like inner and outer surface finish. This clean surface is essential to prevent contamination and localized crevice corrosion in service.
To verify structural integrity before delivery, all pipes undergo a series of mechanical and non-destructive tests:
Our production lines are fully audited and comply with leading global testing and quality standards.
How we are evolving our production capabilities to support the global energy transition.
Expanding our electropolishing facilities to achieve internal surface roughness below Ra 0.25µm, catering specifically to next-generation semiconductor gas delivery systems and sterile bioreactors.
Engineering specialized stainless steel alloys designed to resist hydrogen embrittlement under extreme high-pressure environments (up to 700 bar), supporting the expansion of clean hydrogen fueling networks.
Integrating online Eddy Current testing and continuous laser profiling across all six production lines to ensure 100% defect-free tubing batches before shipment.
Technical details, shipping logistics, and transaction information for international buyers.
Browse our complete product catalog for specialized industrial applications.
