Sihe Steel
Sihe Steel
Engineered in compliance with rigorous ASTM, ASME, JIS, and EN manufacturing standards for high-pressure and corrosion-prone industrial applications.
As industrial systems scale in complexity, structural failures caused by localized corrosion, pitting, or weld joints under high-pressure conditions present major operational and financial hazards. At Liaocheng Sihe Stainless Steel Material LTD, we solve these vulnerabilities by engineering long-length, high-integrity 304 and 316L coiled tubing designed for high-stress applications.
Equipped with six state-of-the-art continuous cold drawing and rolling production lines, our Chinese manufacturing plant supplies custom, high-precision tubing engineered for long-term reliability. We specialize in austenitic grades (304, 304L, 316L, 321, 317L, 309S, 310S) and high-performance super alloys (Incoloy 800/825, Inconel 625, Duplex 2205, Super Duplex 2507) to handle severe service environments globally.
Using advanced inline bright annealing (BA) induction furnace technology, we supply seamless and orbital-weld-free coiled tubing in continuous lengths up to 32,800 feet (10,000 meters). This mitigates potential leak points and installation complexities in critical subsea umbilical bundles and chemical process systems.
How local production clusters, raw material vertical integration, and advanced logistics support global procurement programs.
Our proximity to major Chinese high-grade steel refineries ensures a steady supply of premium, clean-melt hot-rolled bands. This enables tight controls on chemical composition, ensuring low sulfur and controlled nitrogen content for high weldability and corrosion resistance.
We operate advanced protective-atmosphere bright annealing lines. Heating the tubing above 1040°C in a pure hydrogen atmosphere, followed by rapid cooling, prevents chromium carbide precipitation and ensures a scale-free, high-purity surface finish.
Our logistics system provides specialized packing solutions, including custom wooden reels, heavy-duty metal-wood spools, and precision layer winding. We handle international export documents and certifications to secure door-to-port and door-to-door transit.
Comprehensive product dimensions, wall thicknesses, and alloy options manufactured in strict accordance with international standards.
| Material Grade | Outer Diameter (OD) Range | Wall Thickness (WT) Range | Standard Compliance | Available Lengths per Reel |
|---|---|---|---|---|
| 304 / 304L (Austenitic) | 0.125" – 1.00" (3.175mm – 25.4mm) | Up to 0.165" (3.0mm) | ASTM A269 / ASTM A213 / EN 10216-5 | Up to 32,800 ft (10,000 m) |
| 316 / 316L (High-Moly Austenitic) | 0.125" – 1.00" (3.175mm – 25.4mm) | Up to 0.165" (3.0mm) | ASTM A269 / ASTM A213 / JIS G3459 | Up to 32,800 ft (10,000 m) |
| 321 / 321H (Titanium Stabilized) | 0.250" – 0.750" (6.35mm – 19.05mm) | 0.020" – 0.083" (0.5mm – 2.1mm) | ASTM A269 / ASME SA213 | Up to 15,000 ft (4,572 m) |
| Duplex 2205 / Super Duplex 2507 | 0.250" – 0.750" (6.35mm – 19.05mm) | 0.035" – 0.095" (0.89mm – 2.41mm) | ASTM A789 / EN 10216-5 | Up to 10,000 ft (3,048 m) |
| Nickel Alloys (Incoloy 825 / Inconel 625) | 0.125" – 0.625" (3.175mm – 15.875mm) | 0.028" – 0.065" (0.71mm – 1.65mm) | ASTM B163 / ASTM B423 | Custom lengths upon request |
*Note: Tolerances are strictly maintained according to ASTM A269. Average outer diameter tolerance is within ±0.005" (0.13mm), and wall thickness tolerance is restricted to ±10%.
In deepwater oil and gas operations, hydraulic control lines and chemical injection lines run thousands of meters under high external hydrostatic pressure. Traditional straight pipes require orbital weld joints every 6 or 12 meters. Each weld introduces heat-affected zones (HAZ) susceptible to stress corrosion cracking (SCC) and intergranular corrosion.
By using continuous seamless coiled tubing from Liaocheng Sihe, you remove structural discontinuities from your control lines. Our bright-annealed interior surface features a low roughness profile (Ra < 0.4 μm), which minimizes flow friction and prevents paraffin or scale deposition in chemical delivery systems.
For demanding subsea environments, we support engineering design reviews to assist in selecting appropriate materials (e.g., Duplex 2205 or Incoloy 825) to prevent chloride-induced stress corrosion cracking and pitting in offshore installations.
Where precision, long length, and high corrosion resistance are critical to system operations.
Delivers hydraulic control fluids and chemical injection solutions to subsea wellheads. Continuous lengths prevent joint leaks under high pressure.
Serves as durable heat exchanger coils that withstand high temperatures and corrosive geothermal brine or synthetic heat transfer oils.
Seamless 304 and 316L coils feature electro-polished internal surfaces to prevent bacterial contamination and meet strict sanitary standards.
Provides critical fluid lines for chemical analyzer enclosures, chromatographs, pilot plant gas feeds, and marine hydraulic systems.
Value-added processing capabilities designed to deliver installation-ready components to global assembly sites.
We use dedicated CNC bending machinery to process stainless steel coils into tight-radius concentric spirals, helical coils, and complex geometry configurations designed for direct installation in pressure vessels and shell-and-tube heat exchangers.
To eliminate field dressing errors, we provide laser cutting and tube end deburring, squaring, and flanging. This ensures clean fits for orbital welding or mechanical compression fittings.
Our pickling and passivation processes remove free iron from outer and inner tube walls. This promotes a chromium oxide passive film, maximizing corrosion resistance in wet or acidic environments.
Every meter of coiled tubing we ship undergoes strict, non-destructive testing to verify metallurgical integrity and pressure capability. Our factory operates a fully certified, independent testing laboratory.
Detects surface anomalies, micro-cracks, and localized thickness variations along the coil length.
Verifies pressure ratings at up to 10,000 PSI to confirm safety factors.
Confirms ductility and grain structure stability to prevent cracking during installation bends.
Underwater bubble testing and gas leak checks confirm zero micro-porosity.
Checks hardness profiles (HRB < 90) to verify tensile strength matches ASME specifications.
ISO 9001:2015 certified production processes, Mill Test Reports (MTR) matching EN 10204 3.1, and material traceability.
Technical and logistical insights for global procurement departments, engineering firms, and supply chain managers.
Supporting down-stream industrial production with high-performance manufacturing techniques.
Our factory processes custom outer diameters ranging from 6.35mm to 19mm in alloy grades such as 304, 316L, and Duplex 2205 to match targeted design specifications.
We supply precision helical and spiral configurations designed to fit directly into pressure vessels, heat exchangers, and space-constrained enclosures.
We prepare tube ends with flanging and custom flares to support automotive exhaust connections, chemical pipelines, and hydraulic line attachments.
Additional heavy-wall piping, precision tubes, and sheet materials supplied directly from our production facilities.
