Sihe Steel
Sihe Steel
Modern thermal engineering demands heat exchange materials that can withstand elevated operating pressures, corrosive fluids, and extreme thermal cycling. Traditionally, copper tubing was the standard for HVAC networks. However, the rise of modern eco-friendly refrigerants, combined with harsher operation environments (such as offshore installations, coastal marine air conditioning, and industrial manufacturing facilities), has accelerated the shift toward high-performance stainless steel coiled piping.
Compared to copper, stainless steel alloys offer exceptional structural integrity and tensile strength, enabling HVAC designers to decrease tube wall thicknesses while maintaining safety margins under high-pressure scenarios. Crucially, the thermodynamic stability of Austenitic steel grades like 304 and 316L, alongside Duplex 2205 and Super Duplex 2507, prevents stress-corrosion cracking (SCC) and pitting in chloride-heavy atmospheres.
Liaocheng Sihe Stainless Steel Material LTD has engineered a refined product lineup designed specifically to address these modern engineering constraints. Combining seamless drawing technologies with automated bright annealing processes, our coil pipes ensure consistent heat transfer rates, minimal internal friction, and superior cleanability.
Advanced Production Lines
Years of OEM/ODM Expertise
Continuous Maximum Length (32,800 ft)
Countries and Regions Exported
Selecting the ideal stainless steel grade involves balancing corrosion resistance, mechanical strength, thermal conductivity, and manufacturing costs. For typical residential and light commercial HVAC/R systems, austenitic grades such as 304/304L provide a cost-effective choice with excellent formability. In more demanding environments—such as marine cooling towers, pharmaceutical cleanrooms, or high-humidity food processing plants—the enhanced molybdenum content in 316L and 317L is essential for preventing pitting from acidic or salty media.
For extreme-duty setups like offshore oil platforms, subsea umbilical systems, or petrochemical cooling arrays, we offer specialized materials like Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625. These alloys combine high yield strengths with exceptional resilience to stress corrosion cracking, allowing for thinner walls and improved heat transfer efficiency.
| Alloy Grade | UNS Number | Tensile Strength (MPa) | Yield Strength (MPa) | Primary Alloying Elements | Recommended Applications |
|---|---|---|---|---|---|
| 304/304L | S30400 / S30403 | ≥ 485 | ≥ 170 | 18% Cr, 8% Ni | HVAC evaporators, commercial refrigerators, domestic water heaters |
| 316/316L | S31600 / S31603 | ≥ 485 | ≥ 170 | 16% Cr, 10% Ni, 2% Mo | Marine cooling loops, pharmaceutical machinery, chemical process lines |
| Duplex 2205 | S32205 / S31803 | ≥ 655 | ≥ 450 | 22% Cr, 5% Ni, 3% Mo, 0.18% N | High-pressure offshore exchangers, subsea chemical injection lines |
| Super Duplex 2507 | S32750 | ≥ 795 | ≥ 550 | 25% Cr, 7% Ni, 4% Mo, 0.27% N | Deep-water subsea umbilicals, desalination plants, aerospace cooling |
| Incoloy 825 | N08825 | ≥ 586 | ≥ 241 | 38% to 46% Ni, 19.5% to 23.5% Cr | High-temperature heat exchangers, sour gas service, acid processing |
| Inconel 625 | N06625 | ≥ 827 | ≥ 414 | 58% Ni min, 20% to 23% Cr, 8% to 10% Mo | Aerospace propulsion systems, exhaust ducts, highly corrosive subsea wells |
Our manufacturing complex utilizes advanced fabrication technologies designed to maintain close dimensional tolerances, clean interior surfaces, and uniform grain structures. Operating six independent production lines, we support coiled tubing sizes ranging from 0.125 inch (3.175 mm) up to 1 inch (25.4 mm) in outer diameter, with wall thicknesses up to 0.165 inch (3 mm). Single, continuous spool lengths can reach up to 10,000 meters (32,800 feet), minimizing the need for orbital welds in complex piping configurations.
A key capability of our facility is our online bright annealing technology. By processing the stainless steel tubing under a controlled hydrogen atmosphere, we prevent surface oxidation and scale formation, eliminating the need for post-anneal pickling. This softening treatment recovers the material's ductility, ensuring the coiled pipe remains easy to bend and flare during field installation.
To verify the mechanical integrity of our pipes, every meter of tubing undergoes a comprehensive quality check, including non-destructive eddy current testing, pneumatic pressure tests, flaring, compression, and mechanical bending tests. Hardness checks (100% verified) and tensile testing confirm that each batch meets standard criteria before shipment.
In addition to manufacturing standard coiled coils, Liaocheng Sihe provides custom value-added fabrication services. We tailor stainless steel tubing to specific project requirements, reducing assembly times and lowering overall installation costs.
We support various materials (e.g., 304, 316L, 2205) and specifications (diameter 6.35mm to 19mm) for stainless steel coils. This includes bending, spiral forming, and precision drawing processes tailored for high-efficiency heat exchangers and compact HVAC condensers.
Utilizing high-precision laser, mechanical, or flame cutting tools, we deliver accurate cut lengths. Our advanced straightening machinery ensures straightness tolerances suitable for automated orbital welding and tube-to-tubesheet assembly.
We offer specialized surface modification options, including mechanical polishing, chemical passivation, and electro-polishing. These treatments improve corrosion resistance and surface cleanliness, meeting the strict requirements of pharmaceutical and semiconductor processes.
Procuring raw materials for international operations requires careful consideration of local regulations, technical compliance, and logistical stability. At Liaocheng Sihe, we focus on maintaining robust material supply chains and ensuring regulatory compliance. We produce stainless steel coiled tubing in strict accordance with major global standards, including ASTM (e.g., A269, A312, A240), ASME, JIS, EN, and GB.
Our logistical network supports secure, long-distance export packaging designed to protect product shapes during sea, air, and land transit. Through close partnerships with global freight hubs, we coordinate shipping routes that optimize transit times and balance costs for high-volume orders.
Liaocheng Sihe's stainless steel coiled tubes are used in many specialized environments, from industrial cooling systems to offshore energy platforms. We customize our products to meet the unique demands of each industry, ensuring long-term reliability and safety.
Operating a global supply chain requires strategic management of trade policies, raw material price shifts, and manufacturing capacity. Liaocheng Sihe is situated in Shandong, a center of Chinese steel production. This location grants us direct access to high-quality raw materials and efficient production logistics. This positioning allows us to offer cost-effective options compared to regional fabricators in Europe and the Americas, without compromising on quality standards.
Our facility uses automated, high-capacity equipment to handle large-volume orders with consistent turnaround times. Our production lines are designed to adapt to shifting specifications, ensuring we can meet customized mechanical parameters, surface finishes, and strict packaging requirements. By managing our raw material supplies, we help shield our clients from market price fluctuations, supporting stable project planning and budgeting.
Duplex 2205 provides excellent fatigue resistance and mechanical stability.
Precision engineered 1/2 inch coiled tubes for high-pressure systems.
High-temperature grade stainless steel ideal for furnace heat exchange systems.
High nickel content alloys for chemical recovery processes.
Extended lengths up to 10,000 meters for umbilical systems.
Ultra-fine diameters for metering and control equipment.
Designed for high thermal conductivity and low shell-side pressure drop.
Optimized wall thickness for efficient heat transfer.
Ensures tight dimensional tolerances and smooth interior surfaces.
Enhanced safety barriers for critical subsea and hazardous lines.
Designed for reliable use with dual-ferrule compression fittings.
Inconel and Incoloy options for highly corrosive processing environments.
