304 Austenitic Stainless Steel Coil Tube — General-Purpose Corrosion-Resistant Tubing
Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. offers a premium-grade 304 stainless steel coil tube, engineered from the industry-standard 18Cr-8Ni austenitic alloy. As the most widely circulated and commercially established stainless steel grade globally, Type 304 serves as the universal price benchmark and material reference for the entire stainless steel tubing sector. This coil tube product is designed for general-purpose applications where resistance to atmospheric corrosion and weak chemical media is required, making it the default choice across food processing, architectural, chemical, and mechanical industries.
Delivered in continuous coil form, this product provides exceptional versatility for downstream fabrication, allowing customers to cut, form, and size tubes to precise requirements without the limitations of fixed-length stock.
Material & Properties
Type 304 stainless steel is an austenitic chromium-nickel alloy containing approximately 18% chromium and 8% nickel by weight. The austenitic crystal structure, stabilized by nickel, ensures excellent formability, weldability, and ductility at both ambient and elevated temperatures.
- Corrosion Resistance: Outstanding resistance to atmospheric corrosion, weak acids, alkalis, and a wide range of organic and inorganic compounds. Suitable for non-chloride-containing environments.
- Mechanical Properties: Superior tensile strength and elongation, maintaining ductility across a broad temperature range.
- Formability: Excellent cold-workability, enabling seamless bending, rolling, and deep drawing without cracking.
- Weldability: Good welding characteristics with minimal post-weld treatment required for most applications.
- Non-magnetic: Remains non-magnetic in the annealed condition, ideal for electrical and instrumentation applications.
- Hygienic Surface: Naturally smooth, easy-to-clean surface suitable for food-grade and pharmaceutical processing.
Specifications
| Parameter | Specification |
|---|---|
| Material Grade | ASTM A213 TP304 / ASTM A269 TP304 / EN 10217-7 / GB/T 14976 |
| Alloy Composition (min.) | Cr: 18.0% | Ni: 8.0% | C: ≤0.08% | Mn: ≤2.0% | Si: ≤1.0% |
| Outer Diameter Range | 3.0 mm (0.118 in) — 108.0 mm (4.252 in) |
| Wall Thickness Range | 0.30 mm (0.012 in) — 8.0 mm (0.315 in) |
| Delivery Form | Continuous Coil / Straight Lengths Available |
| Surface Finish | 2B, BA (Bright Annealed), No. 4 Brushed, No. 8 Mirror, Custom |
| Tensile Strength (Annealed) | 515 – 730 MPa (74,700 – 105,900 psi) |
| Yield Strength (0.2% Offset) | 205 MPa min. (29,700 psi min.) |
| Elongation (Annealed) | ≥40% |
| Density | 8.0 g/cm³ (0.29 lb/in³) |
| Maximum Service Temperature | 870°C (1,598°F) |
| Operating Temperature Range | −196°C (−320°F) to 870°C (1,598°F) |
| Thermal Conductivity (at 100°C) | 16.3 W/(m·K) (9.3 BTU/hr·ft·°F) |
| Coil Weight | Up to 2,500 kg (5,511 lb) per coil |
Manufacturing Process
The 304 stainless steel coil tube is produced through a rigorous multi-stage manufacturing process ensuring dimensional accuracy, metallurgical integrity, and consistent surface quality:
- Raw Material Selection: Virgin austenitic 304 stainless steel wire rod, sourced from certified mills with traceable heat numbers and full chemical composition verification.
- Piercing & Elongation: The steel billet is heated to forging temperature and pierced to form a hollow tube, followed by multi-pass elongation to achieve intermediate dimensions.
- Hot Rolling: The tube blank is hot-rolled through calibrated rolls to achieve target outer diameter and wall thickness tolerances.
- Pickling & Descaling: Hot-rolled scale is removed via controlled acid pickling to reveal a clean, uniform metal surface.
- Cold Drawing / Cold Pilgering: The tube is cold-worked through precision dies to achieve final dimensions within tight tolerances (±0.1 mm on diameter, ±10% on wall thickness).
- Solution Annealing: Continuous annealing at 1,040–1,120°C (1,892–2,048°F) followed by rapid water quenching to restore full austenitic structure, eliminate work-hardening, and achieve optimal mechanical properties.
- Pickling & Passivation: Post-annealing acid treatment removes oxide scale and establishes a protective chromium-rich passive film for maximum corrosion resistance.
- Surface Finishing: Optional mechanical polishing, electropolishing, or brushing to achieve specified surface roughness (Ra values as low as 0.2 μm).
- Coiling & Packaging: Tubes are coiled onto protective spools, wrapped in moisture-barrier film, and packed in export-grade wooden crates or bundles for safe transit.
Applications
Due to its balanced combination of corrosion resistance, mechanical strength, and cost-effectiveness, 304 stainless steel coil tube finds extensive use across a wide spectrum of industries:
- Food & Beverage Processing: Sanitary tubing for dairy, brewing, juice, and pharmaceutical processing lines where hygienic surfaces and cleanability are critical.
- Architectural & Construction: Structural handrails, balustrades, decorative trim, elevator interiors, and facade elements.
- Chemical Processing: Piping systems for non-aggressive chemical transfer, laboratory apparatus, and reagent handling equipment.
- Automotive & Transportation: Exhaust systems, fuel lines, structural brackets, and interior trim components.
- Medical & Laboratory Equipment: Instrument tubing, surgical device housings, and analytical equipment frames.
- Heating & Cooling Systems: Heat exchanger tubes, condensate lines, and HVAC distribution piping.
- Agricultural Equipment: Irrigation systems, milking equipment, and machinery structural components.
- General Engineering: Machine frames, conveyor systems, scaffolding, and structural support elements.
Quality Certifications
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management framework ensuring every batch of 304 coil tube meets international standards:
- ISO 9001:2015 — Quality Management System certification
- ISO 14001:2015 — Environmental Management System certification
- CE Marking — Compliance with European Conformity standards for pressure and non-pressure applications
- EN 10204 3.1 — Third-party inspection certificates available upon request
- Mill Test Certificates (MTC) — Full chemical composition and mechanical property data provided with every shipment
- ASTM / ASME Compliance — Materials conform to ASTM A213, A269, and ASME BPV Section VIII requirements
- GB/T Standards — Full compliance with Chinese national standards (GB/T 14976, GB/T 12771)
Unique Selling Points: As the global market's most widely available and trusted stainless steel grade, 304 coil tube from Wenzhou Jixing offers unmatched supply chain reliability, competitive pricing as the industry benchmark material, and proven performance across virtually every industrial sector. The continuous coil delivery format eliminates butt-weld joints, reduces fabrication waste, and enables high-throughput automated cutting and forming operations — delivering significant cost and schedule advantages for end users.