Sihe Steel
Sihe Steel
Engineered to strictly conform with international industrial standards (ASTM, ASME, JIS, EN, GB) for challenging operating environments.
Established as a high-precision metal manufacturer in China, Liaocheng Sihe Stainless Steel Material LTD is a premier global exporter specializing in high-performance stainless steel coiled tube, stainless steel polishing tube, and stainless steel seamless coiled tubing. Supported by our advanced metal sheets and pipe divisions, we deliver standard-compliant piping products to meet critical specifications in demanding fields.
Operating six state-of-the-art production lines, including three production lines specifically optimized for long-length seamless coils, we enforce a strict quality control matrix. Our products adhere to international manufacturing standards, including GB, ASTM, ASME, JIS, and EN. We process standard austenitic grades alongside high-performance duplex and nickel alloys, supplying reliable products to partners in over 30 countries across the US, Germany, Spain, South America, Southeast Asia, the Middle East, and Eastern Europe.
To support high-integrity subsea umbilical and oil extraction applications, we introduced advanced bright annealing technology. This setup supports inline softening and thermal stress relief under protective gas conditions, preventing oxidation and maintaining a clean, scale-free internal surface.
We manufacture our capillary and coiled tubes from diverse corrosion-resistant alloys to meet temperature and mechanical demands.
Selecting the appropriate alloy grade is key to preventing crevice corrosion, pitting, stress corrosion cracking, and structural failure in deepwater, chemical processing, or high-temperature steam lines.
For standard environments, 304/304L and 316/316L offer high weldability and reliable corrosion resistance. In higher temperatures and challenging environments, stabilized grades like 321 (titanium-alloyed) or heat-resistant grades like 309S/310S prevent sensitization and maintain high mechanical strength.
For subsea oil extraction, offshore umbilicals, and sour gas handling, we supply high-performance duplex materials like Duplex 2205 and Super Duplex 2507, alongside nickel-base superalloys including Incoloy 800, Incoloy 825, and Inconel 625.
| Alloy Category | Standard Designations | Key Properties & Primary Applications |
|---|---|---|
| Austenitic Stainless Steel | 304, 304L, 316, 316L, 321, 317L, 309S, 310S | Highly weldable and formable. 316L offers excellent resistance to general corrosion and pitting. 321 prevents intergranular corrosion. 310S stands up to high-temperature scaling up to 1100°C. |
| Duplex Stainless Steel | Duplex 2205, Super Duplex 2507 | Provides high mechanical strength alongside resistance to stress corrosion cracking (SCC) and pitting in chloride environments. Used in subsea flowlines and chemical processing plants. |
| Nickel Alloys & Superalloys | INCOLOY 800, Incoloy 825, Inconel 625 | Engineered for extreme conditions. Incoloy 825 resists sulfuric and phosphoric acids. Inconel 625 delivers high temperature resistance and corrosion control in sea water and offshore systems. |
We offer secondary fabrication services, ensuring our stainless steel coils integrate directly into your target assemblies.
We support diverse alloy materials (304, 316L, Duplex 2205) and custom specifications, offering flexible structural adaptations for coiled tubing with outer diameters ranging from 6.35mm to 19mm.
Our services include bending, spiral forming, and precision drawing. We manufacture custom thermal exchange components configured to fit compact heat exchanger housings.
We utilize high-speed laser cutting, mechanical cutting, and cold straightening processes to achieve tight dimensional tolerances and clear, burr-free cuts.
We offer bright annealing, precision polishing, mechanical polishing, and chemical passivation treatment to improve corrosion performance and meet cleanroom standards.
Our team provides end-forming and precision flanging for capillary connections, facilitating reliable sealing and secure integration with automotive exhaust components, chemical manifolds, and instrumentation systems.
Our capillary tubes and continuous seamless coils are engineered to perform in critical systems and demanding operational environments.
As global oil and gas extraction moves into deeper offshore waters, subsea systems are exposed to high hydrostatic pressures, sour reservoir fluids containing H₂S and CO₂, and marine chloride exposure. Our continuous seamless coiled tubing—offered in lengths up to 32,800 feet (10,000 meters)—is designed to eliminate intermediate orbital welds. This design provides structural continuity and high pressure rating, reducing potential leakage pathways in umbilical lines, subsea injection conduits, and hydraulic control systems.
Explore our full line of stainless steel sheets, coils, and specialty capillary tubes configured to diverse industrial envelopes.
Manufactured in Duplex 2205, this coil combines high mechanical yield strength with corrosion resistance in high-chloride marine environments.
Our 1/2-inch stainless steel coiled tubing is designed for high-pressure fluid transfer, chemical injection, and instrument connections.
A specialty high-temperature stainless steel tube suitable for furnace components, kiln fittings, and thermal processing systems.
Manufactured through high-precision rolling, these sheets meet critical dimensional tolerances for stamping, cladding, and fabrication.
Optimized wall thickness up to 3mm (0.165 inch) to resist high burst pressures in hydraulic and downhole applications.
Features outer diameters down to 0.125 inches. Designed for liquid chromatography (HPLC) and precision gas flow control.
Utilizes high-alloy nickel concentrations (Incoloy 825, Inconel 625) to resist acidic environments and pitting.
Features an ultra-smooth internal diameter to prevent scaling, reduce friction losses, and optimize heat transfer rates.
Reliable tubing solutions for instrumentation, pressure vessels, structural conduits, and chemical transport lines.
Manufactured in high-nickel compositions to maintain mechanical integrity under high heat stress.
Features highly polished surfaces and precise dimensional controls, meeting the requirements of surgical and laboratory tools.
Processed via inline bright annealing to prevent scaling, optimize metallurgical microstructure, and maintain material flexibility.
Heavy-duty seamless coils designed for high tensile load capacities and extreme hydrostatic pressure at depth.
Our engineering focus centers on clean internal surfaces, precise wall control, and long continuous length capabilities.
In analytical chemistry and semiconductor manufacturing, any interior micro-roughness or residue can cause fluid drag, sample carryover, or chemical contamination.
Our production lines feature advanced internal mandrel polishing and post-drawing cleaning procedures. This reduces microscopic surface irregularities, ensuring smooth flow paths and clean environments in chromatography and ultra-pure gas delivery lines.
Welds are often the primary site for corrosion and mechanical failure under high pressures. By implementing precision cold-drawing and long-reach pilgering processes, we manufacture continuous coiled tubing up to 10,000 meters (32,800 feet) in length.
This capability supports the production of high-integrity umbilical systems for offshore oil platforms, lowering risk by minimizing the need for mechanical joining methods.
Our testing laboratory performs mechanical and non-destructive evaluations to verify the performance of each production run.
Our testing protocols include 100% pneumatic (air tightness) and hydrostatic validation, positive material identification (PMI) to verify alloy composition, flaring, compression, and mechanical bending tests, as well as surface roughness metrics. Our bright annealing process softens the material inline, maintaining the required mechanical flexibility while keeping the inner surfaces clean.
Answers to common B2B procurement questions regarding our manufacturing processes, logistics, and quality assurance.
Our prices vary depending on alloy raw material costs (LME metal rates), outer diameter, wall thickness, and order volumes. Please contact us with your specifications to receive an updated price list.
Yes, all international orders have an ongoing minimum order quantity. For specialty size runs and custom alloys, MOQ requirements vary. Please consult our sales team for detail.
Yes, we provide comprehensive documentation including Certificates of Analysis (MTR), Mill Test Certificates according to EN 10204 3.1, Certificate of Conformance, Insurance, Origin Documents, and relevant export paperwork.
For standard samples, lead time is approximately 7 days. For mass production runs, the lead time is 20 to 30 days after receiving deposit and final design approval. We adjust production schedules to support urgent project deadlines.
We accept standard corporate bank transfers (T/T), Western Union, and PayPal. Our typical payment terms are a 30% deposit in advance, with the 70% balance paid against a copy of the Bill of Lading (B/L).
We guarantee our material chemistry and manufacturing workmanship. Our team addresses and resolves all quality concerns to satisfy specifications and design requirements.
Yes, we package all shipments in heavy-duty export crates, specialized metal reels, or protective wrapping to prevent deformation. Specialized packaging options can be arranged upon request.
Shipping fees depend on the selected logistics method (sea freight, air freight, or express). Sea freight is the recommended choice for bulk cargo shipments. We calculate freight rates based on package dimensions, weight, and destination.
Additional specifications and materials engineered for specialized industrial and engineering setups.
