Sihe Steel
Sihe Steel
High-performance custom alloy tubing engineered to international standards.
An authoritative analysis of standard practices, material sciences, and commercial trajectories.
In modern industrial fluid-handling systems, stainless steel coiled tubing represents a significant evolutionary leap over traditional straight pipe joints. By eliminating the necessity for intermediate orbital welding and mechanical fittings over long spans, coiled tubing dramatically minimizes leak risks, structural weaknesses, and localized galvanic corrosion. The global industrial landscape demands exceptionally long, continuous conduit lengths for subsea control lines, chemical injection networks, and downhole instrumentation. Today, high-performance alloys are engineered to withstand extreme pressures and corrosive environments, from high-temperature geothermal wells to deepwater offshore gas extraction fields.
The manufacturing process demands extreme metallurgical precision. From initial cold drawing to final inline bright annealing, every step directly impacts the tube's microstructure and mechanical limits. As global projects transition to harsher operational parameters, the industry is shifting from standard austenitic alloys (such as SS 304 and 316L) to highly engineered Duplex, Super Duplex, and Nickel-base superalloys (such as Alloy 825 and Alloy 625). These materials prevent chloride stress-corrosion cracking (SCC) and withstand severe sour service gas (H2S) environments.
Our manufacturing processes adhere strictly to global regulatory frameworks, including GB, ASTM, ASME, JIS, and EN. Every length of tubing is engineered to satisfy the rigorous guidelines laid out by standard ASTM A269 (for general service seamless/welded tubing), ASTM A249 (for boilers, superheaters, heat exchangers, and condenser tubes), and specialized subsea umbilical standards. This compliance ensures our products carry complete material traceability and engineering documentation required for high-risk installations.
Selecting the optimal alloy is critical in mitigating early failure risks. For general instrument lines, AISI 316L remains the benchmark. However, for petrochemical processing and marine environments, duplex grades like Alloy 2205 or superalloys such as Incoloy 825 and Inconel 625 offer vastly superior pitting resistance equivalence numbers (PREN). These specialized alloys prevent localized micro-pitting in high-chloride, acidic fluids, ensuring a maintenance-free design life of over 30 years.
Forging high-performance structural steel and long coiled tubing solutions for a decade.
Liaocheng Sihe Stainless Steel Material LTD is a leading specialist in the engineering and production of premium stainless steel coiled tubes, stainless steel polishing tubes, and seamless coiled tubing. Utilizing six highly specialized production lines, we enforce strict compliance with international manufacturing specifications. Our alloy inventory features standard grades such as 304/304L, 316L, 321, 317L, 309S, 310S, and INCOLOY 800, alongside advanced alloys like Austenitic steel 316L, Duplex 2205, Super Duplex 2507, Incoloy 825, and Inconel 625.
Equipped with advanced manufacturing technology, we supply coiled tubing with outer diameters ranging from 0.125 inches (3.175 mm) to 1 inch (25.4 mm). Wall thicknesses are available up to 0.165 inches (3 mm), with continuous lengths reaching up to 32,800 feet (10,000 meters). This continuous extrusion and drawing capability supports complex umbilical manufacturing for deep-sea oil exploration and gas transport, reducing installation and jointing costs.
A key capability at Liaocheng Sihe is our inline bright annealing technology. Utilizing hydrogen-shielded induction heat treatment, we soften the stainless steel pipe online at temperatures exceeding 1040°C, followed by rapid cooling. This process prevents oxide scale formation on both internal and external surfaces, yielding a mirror-bright, clean, and highly corrosion-resistant finish. This clean ID is critical for capillary lines in analytical chemistry, semiconductor manufacturing, and aerospace hydraulic networks.
How regional supply integration, energy management, and scale lower procurement costs.
Our location in Shandong Province provides direct access to primary domestic steel mills (such as TISCO and Baosteel). This raw material proximity minimizes transport costs, prevents transit damage, and ensures reliable material quality.
By upgrading our three specialized coil lines with continuous welding, drawing, and online testing, we achieve consistent high-volume throughput. This automation significantly reduces labor overhead and shortens production lead times.
With direct connections to major sea terminals like Qingdao Port, shipping times and freight expenses are optimized. This close proximity simplifies international distribution and reduces overall import costs for global buyers.
Standard and custom configurations for industrial and marine grade coiled tubing.
| Material Grade | Common Standards | Outer Diameter (OD) | Wall Thickness (WT) | Max Continuous Length | Primary Industrial Applications |
|---|---|---|---|---|---|
| AISI 304 / 304L | ASTM A269, JIS G3459 | 0.125" - 1.000" (3.18 - 25.4mm) | Up to 0.165" (3.0mm) | 32,800 ft (10,000m) | Food processing, general instrumentation, heat exchangers, automotive fuel lines. |
| AISI 316 / 316L | ASTM A269, EN 10216-5 | 0.125" - 1.000" (3.18 - 25.4mm) | Up to 0.165" (3.0mm) | 32,800 ft (10,000m) | Chemical processing, subsea control lines, oil & gas injection, pharmaceutical systems. |
| Duplex 2205 / 2507 | ASTM A789, EN 10216-5 | 0.250" - 0.750" (6.35 - 19.05mm) | Up to 0.120" (3.0mm) | 16,400 ft (5,000m) | High-chloride marine environments, offshore umbilicals, geothermal wells. |
| Alloy 825 / Inconel 625 | ASTM B423, ASTM B704 | 0.125" - 0.625" (3.18 - 15.88mm) | Up to 0.095" (2.41mm) | 16,400 ft (5,000m) | Sour gas (H2S) service, deep sea petrochemical processing, high-pressure steam boilers. |
Tailored fabrication services to prepare coiled tubes for immediate system integration.
We support various materials (e.g., 304, 316L, 2205) and specifications (diameter 6.35mm to 19mm) for stainless steel coils.
Our processing includes high-precision bending, spiral forming, and precision drawing, tailored specifically for heat exchanger configurations.
Using advanced laser cutting, mechanical cutting, or flame cutting, we deliver clean-cut tube sections that meet strict engineering tolerances.
We develop high-performance surface finishes, including electrochemical polishing, to prevent biological fouling and scaling in fluid channels.
We provide custom end flanging, orbital tube prep, and threading, commonly applied in automotive exhaust setups and chemical process connections.
Supporting critical operations across offshore energy, chemical processing, and aerospace engineering.
Every production run undergoes physical, mechanical, and integrity verification tests.
At Liaocheng Sihe, quality control is integrated throughout our manufacturing process. We conduct comprehensive, in-house testing to verify the structural integrity of our coiled tubing. Our testing protocols include 100% hydrostatic and pneumatic air-tightness testing, hardness testing, tensile strength evaluation, flattening, and reverse-bend testing. These rigorous checks ensure our products perform reliably under the challenging pressure and temperature demands of industrial applications.
Our production facility is certified to meet ISO 9001, PED, and leading marine classification standards. We supply full Mill Test Certificates (MTC) in accordance with EN 10204 3.1, providing detailed chemical composition analysis, mechanical properties, and non-destructive testing reports.
Explore our specialized metal products, from capillary tubes to heat exchanger pipes.
Our duplex 2205 and austenitic alloy coiled tubing options provide reliable corrosion resistance in deep-sea control and chemical injection systems.
We supply coiled tubing in standard 1/2-inch and custom sizes, designed for easy installation and reliable leak prevention in fluid networks.
Designed for high-temperature and oxidized industrial setups, our 310S coils deliver long-term thermal stability.
Small-bore, high-precision capillary lines engineered for chromatography, sensors, and medical instrumentation.
Continuous-length, thin-wall tubes optimized for efficient thermal transfer in heating, cooling, and industrial condenser systems.
Corrosion-resistant steel sheets and structural plates in grades 304, 316L, and 410, suitable for machinery fabrication and storage tanks.
Precision-polished pipes with smooth internal and external surfaces, ideal for high-purity food, beverage, and biotech applications.
High-yield-strength alloy tubes (such as Duplex 2205) engineered for aggressive chemical processing and marine environments.
High-performance Incoloy 825 and Inconel 625 superalloys, engineered for demanding offshore wells and high-acid chemical lines.
Key developments driving engineering standards and alloy selection in the coming years.
The global coiled tubing market is evolving to support deeper offshore drilling and new renewable energy applications. High-temperature and high-pressure (HPHT) wells require tubing materials that offer elevated mechanical limits and resistance to hydrogen embrittlement. As a result, Duplex and Super Duplex alloys are increasingly preferred over standard austenitic grades for downhole and control line applications.
Additionally, the transition to green energy is creating new demands for stainless steel coiled tubing in hydrogen transport and storage systems. Because hydrogen molecules are highly prone to micro-diffusion, pipelines must feature smooth, scale-free inner surfaces to prevent stress cracking. Advanced online quality monitoring technologies, including real-time eddy current inspections and laser profiling, are becoming essential for verifying these critical surface conditions.
Modern subsea and geothermal installations are increasingly utilizing coiled tubing with integrated fiber-optic lines. This configuration enables real-time pressure, temperature, and strain measurements along the entire length of the tube, helping operators detect potential structural issues early and optimize system performance.
Technical and commercial answers to common questions about sourcing stainless steel coiled tubing.
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 direct stock availability.
Yes, we can provide most documentation including Certificates of Analysis / Conformance; Insurance; 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 go over your requirements with your sales representative. In all cases we will try to accommodate your needs. In most cases we are able to do so.
You can make the payment to our bank account, Western Union or PayPal: 30% deposit in advance, 70% balance against the copy of B/L.
We warranty our materials and workmanship. Our commitment is to your satisfaction with our products. In warranty or not, it is the culture of our company to address and resolve all customer issues to everyone's satisfaction.
Yes, we always use high quality export packaging. We also use specialized hazard packing for dangerous goods and validated cold storage shippers for temperature sensitive items. Specialist packaging and non-standard packing requirements may incur an additional charge.
The shipping cost depends on the way you choose to get the goods. Express is normally the quickest but also most expensive way. By sea freight is the best solution for large quantities. Exact freight rates can only be calculated when we have the details of order volume, weight, and delivery method. Please contact us for further information.
Further industrial steel tubing and sheet profiles available for global supply.
