Sihe Steel
Sihe Steel
High-precision stainless steel, super duplex, and nickel alloy tubing designed to meet international manufacturing standards (ASTM, ASME, JIS, EN, GB).
Stainless steel grade 304 (UNS S30400/SUS304) represents the gold standard of austenitic chromium-nickel alloys within the global piping and tubing infrastructure. Characterized by a minimum of 18% chromium and 8% nickel (popularly classified as 18/8), this alloy is engineered to provide an optimal balance of corrosion resistance, structural ductility, and mechanical reliability.
For heavy-duty heat exchangers, precision instrumentation lines, and chemical processing networks, selecting 304 or its low-carbon variant, 304L (UNS S30403), is crucial to avoiding sensitization—a metallurgical phenomenon where chromium carbides precipitate at the grain boundaries during high-temperature exposure (e.g., during welding or operations in the 425°C to 860°C range), leaving the material susceptible to intergranular corrosion.
"By limiting the carbon content to a maximum of 0.03%, Grade 304L suppresses the formation of chromium carbides, preserving structural integrity at weld joints without requiring post-weld annealing."
| Alloy Grade | UNS No. | Chromium (Cr) % | Nickel (Ni) % | Carbon (C) % Max | Tensile Strength (MPa) Min | Yield Strength (MPa) Min |
|---|---|---|---|---|---|---|
| 304 | S30400 | 18.0 - 20.0 | 8.0 - 10.5 | 0.08 | 515 | 205 |
| 304L | S30403 | 18.0 - 20.0 | 8.0 - 12.0 | 0.03 | 485 | 170 |
| 316L | S31603 | 16.0 - 18.0 | 10.0 - 14.0 | 0.03 | 485 | 170 |
| Duplex 2205 | S32205 | 22.0 - 23.0 | 4.5 - 6.5 | 0.03 | 655 | 450 |
The commercial demand for high-integrity 304 stainless steel tubing is accelerating globally. Industrial plants require strict compliance with international manufacturing codes to guarantee performance in volatile operating conditions. From regional sectors to major heavy industries, modern engineering projects require long-lasting components to reduce downtime and prevent fluid line failures.
As a major manufacturing hub for high-grade steel, China houses leading metallurgical clusters capable of large-scale, high-precision processing. Specialized facilities like Liaocheng Sihe Stainless Steel Material LTD deliver high-yield output by deploying advanced, online bright annealing furnaces. This approach enables domestic factories to produce extra-long, seamless coiled tubing (up to 10,000 meters / 32,800 feet) that minimizes the need for orbital welds, mitigating the risk of potential leak points in critical fluid systems.
High-volume, high-precision steel tubing manufacturing executed across fully optimized production lines.
With a ten-year history of precision engineering, Liaocheng Sihe Stainless Steel Material LTD manufactures high-quality sheets, pipes, and specialized coiled tubing. We strictly adhere to standard production codes across domestic and international markets (GB, ASTM, ASME, JIS, EN).
Our core alloy offerings cover a wide metallurgical spectrum to meet varying levels of chemical aggression and temperature stress, including:
A major technological differentiator of Liaocheng Sihe is our integrated, online bright annealing system. Unlike traditional open-air heat treatments that require chemical pickling to remove oxide scale, bright annealing occurs in a controlled pure-hydrogen protective atmosphere. This process maintains a highly reflective, scale-free surface on the tube's interior and exterior, keeping roughness values (Ra) to a minimum and preventing particulate entrapment in high-purity fluid lines.
To verify high structural integrity under elevated pressures, we subject all products to a rigorous, multi-stage testing process:
Value-added operations designed to match custom layouts, complex tube shapes, and strict dimensional tolerances.
We support a broad range of custom specifications, covering tube diameters from 6.35mm to 19mm in materials such as 304, 316L, and Duplex 2205.
Precision bending and spiral forming operations specifically optimized for high-efficiency heat exchangers and coiled cooling loops.
High-precision laser and mechanical cutting systems that deliver square ends without deformation, preparing tubes for direct orbital welding.
Developing custom surface profiles through pickling, mechanical polishing, and bright hydrogen annealing to match chemical and hygienic specifications.
Specialized processing engineered for secure mechanical connections in automotive exhaust networks, hydraulic manifolds, and high-pressure chemical transfer pipelines.
Our high-performance alloy products are regularly selected for deployment in major modern industrial infrastructures.
Every batch of tubing undergoes rigorous quality audits to ensure complete traceability and compliance with global construction codes.
Technical support, procurement logistics, and material selections for global engineering projects.
Our tubing prices depend on several market factors, including LME base nickel/chromium indices, required dimensions, wall thickness, and order volume. Please contact our engineering sales office with your exact specifications to receive a formal quotation and updated price list.
Yes, international shipments require a minimum order quantity to keep logistics cost-effective. For standardized tubing dimensions, our MOQ is flexible. For highly customized dimensions or complex alloys (e.g., Inconel 625, Super Duplex 2507), the MOQ will depend on production setup runs. Contact us to discuss options for smaller trial quantities.
Yes, we provide full metallurgical and export documentation with every shipment. This includes EN 10204 3.1 Mill Test Certificates (MTC), Certificates of Analysis/Conformance (COA), hydrostatic pressure test curves, Eddy Current testing charts, Certificate of Origin (Form E/Form F), and transit insurance policies.
For in-stock tooling configurations and sample runs, our typical dispatch lead time is roughly 7 days. For large-scale production runs, delivery takes 20 to 30 days following receipt of the deposit. Lead times take effect upon metallurgical sign-off and deposit processing.
We accept multiple payment methods for international transactions: Telegraphic Transfer (T/T), L/C, Western Union, and PayPal. Our standard commercial terms are a 30% deposit in advance to initiate production, with the remaining 70% balance payable upon presentation of the Bill of Lading (B/L) copy.
We warranty our raw materials and manufacturing workmanship. We are committed to ensuring long-term product performance. Should any material discrepancy occur, our quality control inspectors will investigate and resolve the issue to ensure customer satisfaction.
Yes, all coiled and straight tubes are packed using heavy-duty export packaging, including reinforced wooden cases, steel frames, and thick plastic wrapping to prevent damage from salt air and maritime transport. We also offer specialized packaging solutions for high-purity cleanroom tubes.
Shipping costs depend on the delivery terms (FOB, CIF, DDP), transport method (ocean freight, air freight, express), shipment weight, and volume. Sea freight offers the most economical solution for bulk orders. Contact our logistics department to obtain precise freight quotes tailored to your destination port.
Explore our specialized stainless steel and nickel alloy products, engineered for severe service environments and high-pressure networks.
