Sihe Steel
Sihe Steel
Select from our wide selection of certified stainless steel capillary, coiled, heat-exchanger, and precision line tubing configurations.
An authoritative guide to manufacturing processes, chemical compositions, tolerance controls, and supply chain strategies.
SS304 requires a minimum of 18% chromium and 8% nickel. This elemental balance creates a self-healing passivated chromium-oxide surface film that blocks oxygen diffusion and resists galvanic corrosion. The inclusion of nitrogen helps stabilize austenite phase configuration and increases yield strength.
With tensile strength ratings ≥ 515 MPa and yield strength values exceeding 205 MPa, SS304 maintains structural stability under high internal pressures. Its elongation index (>40%) supports severe cold deformation without cracking, which is key for long-length coiled tubes.
Traditional open-air heat treatment creates oxide scales that require acid pickling. By contrast, online bright annealing in a dry hydrogen and nitrogen reduction atmosphere eliminates oxide formation, preserving a mirror-like finish (surface roughness Ra < 0.4 μm) and restoring corrosion resistance.
| Material Standard | Grade Designation | Carbon (C) Max % | Chromium (Cr) % | Nickel (Ni) % | Manganese (Mn) Max % | Phosphorus (P) Max % | Silicon (Si) Max % |
|---|---|---|---|---|---|---|---|
| ASTM A312 / A269 | TP304 | 0.08 | 18.0 - 20.0 | 8.0 - 11.0 | 2.00 | 0.045 | 0.75 |
| ASTM A312 / A269 | TP304L | 0.035 | 18.0 - 20.0 | 8.0 - 12.0 | 2.00 | 0.045 | 0.75 |
| ASTM A312 / A269 | TP316L | 0.035 | 16.0 - 18.0 | 10.0 - 14.0 | 2.00 | 0.045 | 0.75 |
| JIS G3459 | SUS304 | 0.08 | 18.0 - 20.0 | 8.0 - 10.5 | 2.00 | 0.045 | 1.00 |
A Tier-1 Chinese Manufacturer Specializing in Long-Length Coiled Tubing and Precision Bright Annealed Lines
Established as a leading specialist in the manufacturing of stainless steel coiled tubes, bright polished tubes, and seamless coiled tubing systems, Liaocheng Sihe Stainless Steel Material LTD operates six state-of-the-art production lines. Over the past decade, we have established ourselves as a reliable supply chain partner for critical piping systems used in demanding industrial environments.
We strictly enforce manufacturing standards including GB, ASTM, ASME, JIS, and EN. Our material capabilities extend beyond standard 304/304L to include:
Our signature product is our long-length seamless coiled tubing. Available in outer diameters from 0.125 inch (3.175 mm) up to 1 inch (25.4 mm), with wall thicknesses up to 0.165 inch (3 mm), we can deliver continuous spool lengths of up to 32,800 feet (10,000 meters) without orbital welds. This is critical for cost-effective offshore umbilical manufacturing and downhole chemical injection lines.
Positioning China-sourced piping within global infrastructure, energy sectors, and high-purity processing systems.
As oil and gas exploration reaches deeper waters, the subsea systems demand higher mechanical safety. Our long-length coiled tubing functions in subsea control lines, umbilical systems, and chemical injection pathways. The continuous seamless structure minimizes weak points, reducing leak risks under high marine pressure.
Thermal power plants, HVAC systems, and petrochemical facilities rely on efficient heat transfer. Our ASTM A269 and ASTM A312 compliant tubing features precise tolerances (down to ±0.05 mm) and high thermal stability, resisting scaling and stress corrosion cracking in high-temperature heat exchangers.
For semiconductor manufacturing, biotechnology, and food processing, fluid paths must remain free of contaminants. Our hydrogen-annealed, bright-polished tubing maintains mirror-like interior walls that prevent particulate trapping and facilitate cleaning validation protocols.
At Liaocheng Sihe, we deliver integrated, application-specific solutions tailored to your operational environment. By analyzing local fluid pressure, temperature variations, chemical exposure, and installation paths, we match requirements to the optimal alloy grade. This proactive consultative approach ensures compliance with regional regulations (such as PED in Europe and ASME in the Americas) and improves long-term pipeline safety.
Value-added fabrication and precision processing support customized to client engineering drawings.
We support a broad spectrum of structural configurations across materials including 304/304L, 316L, and Duplex 2205, with outer diameters ranging from 6.35 mm to 19 mm.
Our workshop performs complex bending, spiral coil coiling, and precision drawing, producing custom shapes ready for heat exchanger and boiler installations.
We utilize specialized laser cutting, mechanical abrasive wheel sawing, and precise flame cutting systems to deliver exact lengths with burr-free, clean ends.
We provide chemical passivation, mechanical polishing, and bright annealing processing to ensure clean surfaces and high corrosion resistance.
We offer customized end flanging, flaring, and expansion processes, suitable for connections in automotive exhaust and chemical process piping.
Where our certified stainless steel pipes and coiled tubes are deployed globally.
Shell and tube thermal exchange units.
High pressure refrigerant and coolant loops.
Handling organic and inorganic chemical feeds.
Sanitary piping, brewing, and dairy systems.
Sterile fluid flow lines and bio-reactors.
Superheater loops and condenser pipe systems.
High temperature oil refining process lines.
High performance hydraulic and fuel delivery.
Innovating metallurgical standards and processing technologies to support modern industrial fluid dynamics.
We are optimizing trace amounts of titanium, niobium, and nitrogen within the SS304 matrix to improve long-term thermal strength. This micro-alloying process restricts carbide precipitation along grain boundaries, enhancing resistance to intergranular corrosion in high-heat zones.
We use automated cold-drawing benches with real-time laser monitoring to maintain tight dimensional control. This process achieves uniform wall thicknesses, preventing localized thin areas that could lead to failure under pressure spikes.
By partnering with energy-efficient steel mills that utilize electric arc furnaces and recycled scrap feeds, we help lower the carbon footprint of our raw materials, supporting corporate sustainability objectives.
Every batch of tubing undergoes rigorous non-destructive and physical tests to guarantee safe field performance.
We conduct flaring, flattening, and bending tests to verify that the tubing material handles structural forming and installation bends without micro-cracking or localized wall thinning.
Every tube is subjected to high-pressure water and air tightness testing to verify structural soundness under conditions exceeding standard field pressures.
We use inline eddy current and ultrasonic scanners to search for internal cracks or inconsistencies, ensuring consistent wall quality across long continuous lengths.
Find direct answers about pricing, order minimums, documentation, shipping, and quality assurance.
2205 stainless steel is a duplex stainless steel containing austenitic and ferritic phases...
1/2 stainless steel coiled tubing refers to a coil of stainless steel tubing...
China 310 Steel Coil Tube Factories make high temperature and corrosion resistant coils...
Select from our range of stainless steel capillary tubes, heat exchanger pipes, and customized coil lines.
