304 Austenitic Stainless Steel Coil Tube
Product Overview
The 304 Stainless Steel Coil Tube manufactured by Wenzhou Jixing Metal Materials Co., Ltd. is a premium-grade austenitic stainless steel product designed for general-purpose industrial applications. As the most widely circulated stainless steel grade globally, 304 serves as the industry's price benchmark and performance reference standard. Supplied in continuous coil form, this product offers exceptional versatility, consistent mechanical properties, and outstanding resistance to atmospheric corrosion and weak corrosive media, making it the ideal choice for applications demanding reliability, formability, and cost-efficiency.
Material & Properties
The 304 grade is an 18Cr-8Ni austenitic stainless steel with a face-centered cubic (FCC) crystal structure. Its composition and microstructure confer the following key properties:
- Corrosion Resistance: Excellent resistance to atmospheric corrosion, weak acids, alkalis, and various oxidizing media. The chromium oxide passive film self-repairs in the presence of oxygen, providing long-term surface protection.
- Mechanical Properties: Good tensile strength, high ductility, and excellent cold-formability, enabling seamless bending, welding, and deep drawing without cracking.
- Weldability: Superior weldability with minimal distortion and excellent joint integrity, suitable for all standard welding processes including TIG, MIG, and resistance welding.
- Non-Magnetic: In the annealed condition, 304 is essentially non-magnetic, making it suitable for electromagnetic-sensitive applications.
- Hygienic Surface: Can be polished to a smooth, sanitary finish suitable for food-grade and pharmaceutical environments.
- Temperature Range: Maintains mechanical integrity from cryogenic temperatures up to approximately 870°C (1600°F), with continued corrosion resistance at elevated temperatures.
Specifications
| Parameter | Specification |
|---|---|
| Material Grade | 304 (AISI 304 / SUS304 / 1.4301) |
| Chemical Composition (Typical) | C ≤ 0.08% | Si ≤ 1.00% | Mn ≤ 2.00% | P ≤ 0.045% | S ≤ 0.030% | Cr 18.0–20.0% | Ni 8.0–10.5% | Fe Balance |
| Product Form | Continuous Coil Tube |
| Outer Diameter | 6.0 mm – 168.3 mm (custom sizes available) |
| Wall Thickness | 0.5 mm – 12.0 mm |
| Coil Length | Up to 1,000 m per coil (standard); custom lengths upon request |
| Surface Finish | No.1 Hot-Rolled | 2B Cold-Rolled | BA Bright Annealed | Pickled & Passivated | Polished (4K / 8K / Mirror) |
| Manufacturing Method | Seamless (Pierce & Roll) | Welded (ERW / Laser Welded) |
| Tensile Strength | ≥ 520 MPa (annealed condition) |
| Yield Strength | ≥ 205 MPa (annealed condition) |
| Elongation | ≥ 40% |
| Hardness | ≤ 210 HB (annealed condition) |
| Density | 7.93 g/cm³ |
| Applicable Standards | ASTM A269 / A270 | ASME SB99 / SB199 | EN 10216-5 | GB/T 12771 |
| Heat Treatment | Solution Annealing (1010–1150°C) followed by rapid water quench |
| Packaging | Export-grade wooden crates, steel-banded coils, or custom packaging as required |
Manufacturing Process
Wenzhou Jixing Metal Materials Co., Ltd. employs a rigorous multi-stage manufacturing process to ensure the highest quality 304 stainless steel coil tubes:
- Raw Material Selection: High-purity 304 stainless steel billets and strip are sourced from certified mills with full traceability of chemical composition and metallurgical history.
- Forming: Seamless tubes are produced via the pierce-and-roll (AER) method or plug-rolling process, while welded tubes are manufactured using ERW (Electric Resistance Welding) or laser welding technology for superior weld integrity.
- Precision Sizing: Multi-stand cold-rolling and cold-drawing operations achieve exact dimensional tolerances, smooth internal surfaces, and uniform wall thickness.
- Heat Treatment: Solution annealing at 1010–1150°C followed by rapid quenching eliminates residual stresses, restores full austenitic microstructure, and maximizes corrosion resistance.
- Surface Treatment: Acid pickling and passivation remove scale and contaminants, establishing a stable chromium oxide passive film. Optional polishing stages achieve the desired surface finish.
- Quality Inspection: Every coil undergoes comprehensive non-destructive testing (EDDY current, hydrostatic pressure, ultrasonic) and visual inspection to ensure zero-defect output.
- Coiling & Packaging: Tubes are coiled to the required length and packaged with moisture-proof wrapping, protective end caps, and steel strapping for safe international shipment.
Applications
The 304 stainless steel coil tube is the industry standard for a vast range of applications across multiple sectors:
- Food & Beverage Processing: Piping systems, heat exchangers, fermentation tanks, and hygienic processing lines where sanitary-grade surface finish and corrosion resistance are critical.
- Pharmaceutical & Biotechnology: Clean-in-place (CIP) systems, reactor vessels, and process piping requiring non-contaminating, easy-to-sanitize materials.
- Chemical & Petrochemical: Transfer lines, condensers, and storage systems handling weak acids, alkalis, and oxidizing chemicals at moderate temperatures.
- Energy & Power Generation: Boiler feedwater systems, solar thermal collectors, heat exchanger coils, and condensate return lines.
- Automotive: Exhaust system components, fuel lines, and structural tubing requiring formability and moderate corrosion resistance.
- Construction & Architecture: Structural supports, handrails, decorative elements, and building facades exposed to outdoor atmospheric conditions.
- Appliances & Household: Water heaters, washing machines, kitchen equipment, and heating/cooling system tubing.
- Marine & Coastal Environments: Structural components and piping systems in moderate marine exposure conditions.
Quality Certifications
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system ensuring every batch of 304 stainless steel coil tube meets international standards:
- ISO 9001:2015 — Quality Management System certification ensuring consistent production quality and process control.
- ISO 14001:2015 — Environmental Management System certification demonstrating commitment to sustainable manufacturing practices.
- CE / PED 2014/68/EU — Conformity with European Pressure Equipment Directive for pressure-vessel and piping applications.
- EN 10204 3.1 — Mill test certificates (MTC) issued for every lot, documenting chemical composition, mechanical properties, and heat treatment data.
- ASTM / ASME Compliance — Products manufactured and tested in accordance with ASTM A269, A270, ASME SB99, and SB199 specifications.
- NACE / ISO 21809-1 — Coating and surface preparation standards for corrosion protection in aggressive environments.
Each shipment is accompanied by a full Mill Test Certificate (MTC) and Inspection Report, providing complete traceability from raw material to finished product. Third-party inspection by organizations such as SGS, Bureau Veritas, or TÜV is available upon request.
Unique Selling Points
Industry Benchmark Grade — Maximum Market Availability
As the world's most widely traded stainless steel grade, 304 offers unmatched supply chain reliability, competitive pricing, and broad compatibility with standard fabrication tools and processes. Choosing 304 coil tube ensures the lowest total cost of ownership without compromising on performance.
- Superior Formability: The austenitic microstructure of 304 allows complex bending, rolling, and deep-drawing operations with minimal risk of cracking — ideal for coil tube applications requiring precision shaping.
- Comprehensive Corrosion Protection: The 18% chromium content forms a robust, self-healing passive oxide layer that provides excellent resistance to atmospheric corrosion and weak corrosive media, extending service life significantly.
- Cost-Effective Solution: As the market's price benchmark, 304 delivers the best value proposition among austenitic stainless steels, making it the preferred choice for high-volume industrial procurement.
- Wide Application Versatility: From food-grade sanitary systems to structural construction, 304 coil tube covers the broadest range of end-use applications of any stainless steel grade.
- Full Traceability & Compliance: Every coil is accompanied by complete mill documentation, ensuring regulatory compliance and quality assurance for international markets.
- Customization Capability: Wenzhou Jixing Metal Materials Co., Ltd. offers tailored dimensions, surface finishes, coil lengths, and packaging solutions to meet specific project requirements.