Stainless Steel Coil Tube (Coiltube) — Wenzhou Jixing Metal Materials Co., Ltd.
Product Overview
The Stainless Steel Coil Tube (also referred to as Coiltube) is a precision-engineered, cold-drawn or hot-rolled tubular product supplied in continuous coil form. Manufactured by Wenzhou Jixing Metal Materials Co., Ltd., this product is designed for applications requiring high corrosion resistance, mechanical strength, and dimensional accuracy. The coil format offers significant logistical advantages, including reduced material waste, streamlined downstream processing, and efficient handling in high-volume production environments.
Unlike straight-length tubes, coil tubes are wound onto a heavy-gauge steel spool, enabling uninterrupted feeding into automated forming, bending, welding, and machining lines. This makes them ideal for industries that demand continuous production cycles with minimal interruption.
Material & Properties
Wenzhou Jixing Metal Materials Co., Ltd. offers coil tubes in a range of austenitic, ferritic, and duplex stainless steel grades, each selected to meet specific performance requirements:
- Austenitic Grades (e.g., 304, 304L, 316, 316L, 321, 310S): Provide excellent corrosion resistance, weldability, and formability. Grade 316L offers superior resistance to chlorides and pitting corrosion, making it suitable for marine and chemical environments.
- Ferritic Grades (e.g., 430, 444): Offer good oxidation resistance and lower cost while maintaining adequate corrosion performance for less demanding applications.
- Duplex Grades (e.g., 2205, 2507): Deliver high tensile strength and exceptional resistance to chloride-induced stress corrosion cracking (SCC), suitable for high-pressure and high-temperature service.
Key Mechanical Properties (Typical — Grade 304)
- Tensile Strength: 515–720 MPa
- Yield Strength: ≥ 205 MPa
- Elongation: ≥ 40%
- Density: 8.0 g/cm³
- Maximum Service Temperature: 870°C (oxidizing atmosphere)
- Corrosion Resistance: Excellent resistance to atmospheric, aqueous, and mild chemical environments
Specifications
| Parameter | Specification / Range |
|---|---|
| Outer Diameter (OD) | 6.0 mm – 159.0 mm (custom sizes available upon request) |
| Wall Thickness | 0.3 mm – 6.0 mm |
| Coil Length | Typically 50 m – 300 m per coil (configurable) |
| Coil Spool Weight | Up to 2,500 kg (subject to dimensional constraints) |
| Surface Finish | No. 1 (Hot-Rolled), 2B (Cold-Rolled), BA (Bright Annealed), No. 4 (Brushed), Mirror (8K) |
| Tolerance on OD | ±0.1 mm (standard); ±0.05 mm (precision grade) |
| Tolerance on Wall Thickness | ±0.05 mm (standard); ±0.02 mm (precision grade) |
| Applicable Standards | ASTM A554, ASTM A213, GB/T 14976, GB/T 12771, EN 10217, ISO 3506 |
| Available Grades | 304, 304L, 316, 316L, 321, 310S, 430, 444, 2205, 2507, 904L |
| Heat Treatment | Solution Annealed (1050°C – 1150°C water quench) |
| Packaging | Wooden crate or steel frame with moisture-proof wrapping; seaworthy export packaging available |
Manufacturing Process
The production of Wenzhou Jixing's stainless steel coil tubes follows a rigorous, multi-stage process to ensure dimensional precision, metallurgical integrity, and surface quality:
- Raw Material Sourcing & Ingot Casting: High-purity stainless steel billets are sourced from certified mills. Composition is verified via spectroscopic analysis to ensure compliance with the target grade specification.
- Hot Rolling: Billets are reheated to 1,100°C – 1,250°C and hot-rolled into seamless tube blanks with controlled dimensional tolerances. The hot-rolled coil tube retains a No. 1 surface finish.
- Piercing & Elongation: The hot-rolled tube blanks are pierced to form seamless hollow sections, which are then elongated through a series of mandrel-die stations to achieve the target OD and wall thickness.
- Solution Annealing & Pickling: Tubes are solution-annealed in a continuous annealing furnace (CAF) or batch furnace at 1,050°C – 1,150°C followed by rapid water quenching. This dissolves carbides, restoring full corrosion resistance and ductility. The tubes are then acid-pickled to remove scale and discoloration.
- Cold Drawing (Optional): For precision-grade products, tubes undergo cold drawing through a series of progressively smaller dies to achieve tighter tolerances (±0.05 mm OD, ±0.02 mm wall) and improved mechanical properties.
- Surface Finishing: Depending on the customer specification, tubes may be cold-rolled (2B), bright annealed (BA), brushed (No. 4), or polished to a mirror finish (8K) using automated electropolishing or mechanical polishing lines.
- Coiling & Spooling: Finished tubes are fed onto precision-wound spools using a controlled tension system to prevent kinking, ovality, or surface damage. Each coil is labeled with heat number, grade, dimensions, and production date.
- Final Quality Inspection: Every coil undergoes 100% dimensional verification, visual surface inspection, and — as applicable — non-destructive testing (NDT) including eddy current (EC) inspection, ultrasonic testing (UT), and hydrostatic pressure testing.
Applications
Wenzhou Jixing's stainless steel coil tubes serve a wide spectrum of industrial applications:
- Automotive & Aerospace: Exhaust system components, fuel lines, hydraulic lines, and structural tubing requiring high strength-to-weight ratios and corrosion resistance.
- Food & Beverage Processing: Conveyance piping, heat exchangers, and sanitary-grade tubing compliant with FDA and EHEDG standards.
- Chemical & Petrochemical Industry: Process piping, reactor internals, and corrosion-resistant heat exchanger tubes in aggressive chemical environments.
- Marine & Offshore: Seawater systems, ballast lines, and offshore platform structural tubing where chloride resistance is critical.
- Medical & Pharmaceutical: Surgical instrument tubing, medical gas lines, and pharmaceutical processing equipment requiring biocompatibility and autoclavability.
- Architectural & Decorative: Handrails, balustrades, facade elements, and interior design applications where aesthetic surface finish is paramount.
- Energy & Power Generation: Boiler tubes, heat exchanger coils, and superheater tubes in thermal power plants and nuclear facilities.
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management framework to ensure product reliability and regulatory compliance:
- ISO 9001:2015 — Quality Management System certification, demonstrating adherence to internationally recognized quality processes.
- ISO 14001:2015 — Environmental Management System certification, reflecting commitment to sustainable manufacturing practices.
- ISO 45001:2018 — Occupational Health and Safety Management System certification.
- NACE MR0175 / ISO 15156 — Compliance for sour service applications (H₂S-containing environments).
- EN 10204 3.1 Certificate — Third-party material test certificates available upon request, providing independent verification of chemical composition and mechanical properties.
- Mill Test Reports (MTR): Every heat batch is accompanied by a detailed mill test report documenting chemical analysis (C, Cr, Ni, Mo, N, S, Si, Mn, P), mechanical test results, and heat treatment parameters.
Unique Selling Points
- Continuous Coil Supply: Eliminates butt-weld joints inherent in straight-length tubes, reducing leak risk and improving fatigue resistance in continuous service.
- Minimal Material Waste: The coil format enables near-net-shape cutting, reducing offcuts and material loss by up to 15% compared to straight-length procurement.
- Wide Grade Selection: From standard austenitic (304/316) to advanced super-austenitic (904L) and duplex (2507) grades, accommodating the most demanding corrosion environments.
- Precision Dimensional Control: Cold-drawing capability delivers tolerances as tight as ±0.05 mm on OD and ±0.02 mm on wall thickness, suitable for precision instrumentation and medical applications.
- Custom Surface Finishes: Full range from industrial No. 1 to decorative 8K mirror polish, covering both functional and aesthetic requirements.
- Traceability: Full heat-to-heat traceability from raw material ingot through final coil, ensuring complete supply chain accountability.
Ordering Information
Customers are advised to specify the following parameters when placing an order:
- Stainless steel grade (e.g., 304, 316L, 2205)
- Outer diameter (OD) and wall thickness
- Required coil length and approximate coil weight
- Surface finish specification
- Applicable standard (ASTM, GB, EN, ISO)
- Required certifications and test reports (EN 10204 3.1, NACE, etc.)
- Special packaging or labeling requirements
Note: All specifications listed herein are subject to revision without prior notice. For the most current product data, material certifications, and pricing, customers are encouraged to contact Wenzhou Jixing Metal Materials Co., Ltd. directly. Custom-dimensioned and non-standard grade coil tubes are available upon consultation with our technical sales engineering team.