Sihe Steel
Sihe Steel
Premium grade industrial tubing manufactured strictly according to international standards (GB, ASTM, ASME, JIS, EN)
In modern precision engineering, the 304 Stainless Steel Capillary Tube represents a cornerstone material solution, bridging the gap between micro-fluidic management and structural robustness. Characterized by its narrow inner and outer diameter tolerances, high dimensional precision, and excellent mechanical characteristics, 304 (UNS S30400 / EN 1.4301) capillary tubing is indispensable in industries requiring high-performance resistance to thermal strain, mechanical wear, and chemical erosion.
At Liaocheng Sihe Stainless Steel Material LTD, we operate as a top-tier manufacturer and global exporter, managing six advanced production lines dedicated to processing premium steel types. We strictly adhere to standard specifications including GB, ASTM, ASME, JIS, and EN. Our core material grades extend across a comprehensive range: from traditional austenitic grades (304, 304L, 316L, 321, 317L, 309S, 310S) to advanced alloys such as INCOLOY 800, Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625.
Our manufacturing philosophy emphasizes extreme precision. With coiled tubing options spanning outside diameters from 0.125 inches (3.175 millimeters) up to 1 inch (25.4 millimeters) and wall thicknesses reaching up to 0.165 inches (3 millimeters), we deliver tailored micro-fluidic components designed for long-term deployment. For complex offshore and subsea environments, we support single continuous lengths up to 32,800 feet (10,000 meters) without orbital welds, drastically minimizing potential leak paths in subsea umbilical assemblies.
Comprehensive metallurgical database comparing grade performance matrices under severe operating parameters.
| Steel Grade | UNS / EN Designation | Tensile Strength (MPa) | Yield Strength (0.2% Offset, MPa) | Key Performance Attribute | Primary Industrial Utility |
|---|---|---|---|---|---|
| 304 / 304L | UNS S30400 / 1.4301 | ≥ 515 | ≥ 205 | General corrosion resistance & ductility | HVAC, Medical Cannula, Instrumentation |
| 316L | UNS S31603 / 1.4404 | ≥ 485 | ≥ 170 | High resistance to chloride pitting | Marine, Pharmaceutical, Chromatography |
| Duplex 2205 | UNS S32205 / 1.4462 | ≥ 655 | ≥ 450 | Dual-phase strength & stress corrosion cracking resistance | Subsea Umbilicals, Chemical Processing |
| Incoloy 825 | UNS N08825 / 2.4858 | ≥ 586 | ≥ 241 | Superior resistance in hot sulfuric/phosphoric acids | Sour Gas Wells, Chemical Heat Exchangers |
| Inconel 625 | UNS N06625 / 2.4856 | ≥ 827 | ≥ 414 | High temperature oxidation & fatigue resistance | Aerospace Engines, Nuclear Reactor Components |
Selecting the ideal alloy is crucial for performance optimization. While 304 stainless steel serves as the benchmark alloy for general-purpose applications, the addition of molybdenum in grade 316L, or the biphasic structure of Duplex 2205, provides higher threshold protection in aggressive environments.
Inside our integrated metallurgical production facility in Liaocheng: leading with world-class bright annealing technology.
We have integrated world-class bright annealing facilities. Under a dry hydrogen shielding gas environment, our inline induction furnaces perform recrystallization softening without oxygen exposure. This eliminates surface oxidation, leaving a bright, scale-free inner and outer surface finish that prevents flow friction and particle retention in capillary paths.
Our quality assurance program is designed to meet strict regulatory standards. Every production run undergoes hydrostatic pressure tests, air tightness tests, ultrasonic inspections, tensile/compression analysis, flaring/bending deformation limit validations, and 100% Rockwell/Vickers hardness checks, ensuring zero leakage in high-pressure oil field installations.
By eliminating intermediate butt welds, our continuous cold-drawing process yields coils up to 10,000 meters long. This reduces potential leak points in deep-water subsea oil/gas extraction lines and umbilical tubing projects where extreme marine safety is required.
Engineered options customized to meet your exact geometry and application specs.
Supports various materials (e.g., 304, 316L, 2205) and specifications (diameter 6.35mm to 19mm) for stainless steel coils.
Includes bending, spiral forming, precision drawing, and other processes tailored for industrial heat exchangers.
Laser cutting, mechanical cutting, or flame cutting for high-precision and efficient material processing.
Mechanical polishing, electro-polishing, and pickling passivation to ensure excellent inner and outer surface roughness values.
Precision flanging used in automotive exhaust systems, chemical pipelines, and precision instrument connections.
From deep-sea umbilical lines to medical instrumentation: where quality is non-negotiable.
The global market demand for stainless steel capillary tubing is driven by clean energy integration, microfluidics, and deep-water hydrocarbon extraction. Over the past year, demand has shifted toward higher alloy purity, precise internal surface finishes, and extra-long, weld-free coiled lengths.
With offshore drilling pushing into extreme depths, subsea control lines and umbilical cables must withstand high pressure and aggressive corrosive environments. Liaocheng Sihe specializes in manufacturing high-alloy coiled tubing (including Duplex 2205, Incoloy 825, and Inconel 625) designed to prevent chloride stress cracking and galvanic erosion under high subsea pressures.
In chromatography and medical devices, the smooth inner surface of 304 capillary tubes is crucial. Our oxygen-free bright annealing technology prevents chemical reactions with moving fluids, ensuring reliable and repeatable performance.
Explore our targeted product categories developed through state-of-the-art metallurgical technologies.
2205 stainless steel is a duplex stainless steel containing austenitic and ferritic structures, offering superior yield strength.
1/2 stainless steel coiled tubing refers to a coil of stainless steel tubing with a 0.5-inch nominal outer diameter.
Our factory produces high-temperature-resistant 310 series stainless steel coiled tubes designed for heat treatment systems.
Liaocheng Sihe is certified to ISO 9001 and international marine industry standards, ensuring compliance for all operations.
To ensure the performance of our capillary tubing in critical environments, our facility in Liaocheng runs rigorous testing protocols on every production batch. We conduct chemical composition analyses using optical emission spectroscopy to verify element ratios (Cr, Ni, Mo) meet ASTM A269 requirements.
Mechanical testing verifies ductility and strength limits. Flaring and flattening tests ensure our tubes can undergo field bending and integration without cracking. In addition, 100% of our tubes undergo hydrostatic testing and eddy current inspections to detect internal faults.
This systematic focus on quality allows our products to be exported to over 30 countries, including the US, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe, ensuring reliable performance in critical applications.
Expert answers to common technical, procurement, and logistics inquiries.
Our prices are subject to change depending on supply and other market factors. We will send you an updated price list after your company contacts us for further information.
Yes, we require all international orders to have an ongoing minimum order quantity. If you are looking to resell but in much smaller quantities, we recommend you check out our website for updated terms.
Yes, we can provide most documentation including Certificates of Analysis / Conformance (MTR); Insurance; Certificate of Origin, and other export documents where required.
For samples, the lead time is about 7 days. For mass production, the lead time is 20-30 days after receiving the deposit payment. The lead times become effective when (1) we have received your deposit, and (2) we have your final approval for your products. If our lead times do not work with your deadline, please discuss your requirements with your sales representative. We will try to accommodate your needs in most cases.
You can make payments to our bank account, Western Union, or PayPal: 30% deposit in advance, and the remaining 70% balance against the copy of the Bill of Lading (B/L).
We warranty our materials and workmanship. Our commitment is to ensure your satisfaction with our products. Whether covered by warranty or not, our company culture is to address and resolve all customer issues to mutual satisfaction.
Yes, we always use high-quality export packaging. We also use specialized hazardous materials packaging for dangerous goods and validated cold storage shippers for temperature-sensitive items. Custom or non-standard packaging requirements may incur an additional charge.
The shipping cost depends on the delivery method you choose. Express is typically the fastest but most expensive option. Ocean freight is the recommended solution for large volumes. We can provide accurate freight rates once we know the details of your order size, weight, and shipping method. Please contact us for further details.
Supporting diverse global projects with verified alloy chemistry and structural consistency.
