Stainless Steel Coil Tube — Coiltube Product Technical Specification
Manufacturer: Wenzhou Jixing Metal Materials Co., Ltd. (温州吉兴金属材料有限公司)
Product Category: Stainless Steel Coil Tube (Coiltube)
Product Code: 630
1. Product Overview
Stainless steel coil tubes are continuous, helically wound tubular products manufactured from austenitic, ferritic, or duplex stainless steel alloys. Unlike seamless or welded straight-length tubes, coil tubes are produced in continuous coils, enabling high-volume, cost-efficient supply for downstream fabrication and processing industries. The coil tube format minimizes waste, reduces handling requirements, and facilitates automated cutting, bending, and forming operations.
Wenzhou Jixing Metal Materials Co., Ltd. specializes in the supply of high-quality stainless steel coil tubes adhering to international standards including ASTM (American Society for Testing and Materials), EN (European Norms), ISO (International Organization for Standardization), and GB (Chinese National Standards). The company's coil tube products are engineered for dimensional precision, mechanical integrity, and corrosion resistance across a broad spectrum of industrial applications.
2. Material & Properties
The stainless steel coil tubes are fabricated from a range of alloy grades, each selected to meet specific performance requirements:
- Austenitic Grades: 304 (UNS S30400), 304L (UNS S30403), 316 (UNS S31600), 316L (UNS S31603), 321 (UNS S32100), 310 (UNS S31000)
- Ferritic Grades: 430 (UNS S43000), 409 (UNS S40900), 446 (UNS S44600)
- Duplex Grades: 2205 (UNS S32205), 2507 (UNS S32750)
- Custom Alloys: Available upon request per customer specifications
Key Mechanical Properties (Typical Values for Grade 304):
- Tensile Strength (Ultimate): ≥ 515 MPa
- Yield Strength (0.2% offset): ≥ 205 MPa
- Elongation: ≥ 40%
- Hardness (HB): ≤ 217
- Operating Temperature Range: −196 °C to +870 °C
3. Specifications
| Parameter | Specification Range | Standard Reference |
|---|---|---|
| Outer Diameter (OD) | Φ3.0 mm – Φ325.0 mm | ASTM A269 / A554, EN 10217, GB/T 12771 |
| Wall Thickness | 0.3 mm – 12.0 mm | ASTM A269 / A554, EN 10217, GB/T 12771 |
| Coil Length (Continuous) | 50 m – 500 m per coil | Manufacturer Specification |
| Coil Inner Diameter | Φ150 mm – Φ600 mm | Customer Requirement |
| Surface Finish | No. 1, 2B, BA (Bright Annealed), No. 4, No. 8, HL, Custom | ASTM A480, EN 10088 |
| End Condition | Plain cut, Beveled, Threaded, Flanged | Per Customer Drawing |
| Tolerance (OD) | ±0.05 mm to ±1.0 mm (per size) | ASTM A478, EN 10217 |
| Tolerance (Wall Thickness) | ±10% (or ±0.05 mm, whichever is greater) | ASTM A478, EN 10217 |
| Delivery Condition | Hot Rolled, Cold Drawn, Solution Annealed, Pickled | ASTM A269, EN 10217 |
4. Manufacturing Process
The production of stainless steel coil tubes at Wenzhou Jixing Metal Materials Co., Ltd. follows a rigorously controlled multi-stage process:
- Raw Material Preparation: High-purity stainless steel slabs or strip are sourced from certified mills, verified through chemical composition analysis (spectroscopic testing) and mechanical property certification.
- Forming & Welding: Cold-rolled strip is fed through precision forming rollers to achieve the target tube geometry. The seam is welded using TIG (Tungsten Inert Gas) or LTW (Laser-Tungsten Hybrid) welding technology, ensuring minimal heat-affected zone and superior seam integrity.
- Heat Treatment: Tubes undergo solution annealing at temperatures between 1010 °C and 1150 °C followed by rapid water quenching to restore full austenitic microstructure and maximize corrosion resistance.
- Pickling & Passivation: The annealed tubes are pickled in a mixed acid bath (HNO₃/HF or H₂SO₄/HNO₃) to remove oxide scale, followed by passivation to establish a stable chromium oxide film.
- Coiling: Continuous tubes are wound onto precision coils with controlled tension to prevent deformation, kinking, or ovality. Each coil is protected with moisture-absorbent packaging and VCI (Volatile Corrosion Inhibitor) paper wrapping.
- Hole Inspection (验孔): A critical quality control step — the novel coil tube hole inspection methodology developed and implemented by the company ensures that every tube section is verified for internal bore integrity, wall thickness uniformity, and absence of internal defects. This advanced inspection technique significantly improves inspection throughput and defect detection accuracy compared to conventional sampling methods.
5. Unique Selling Points — Coil Tube Hole Inspection Innovation
A distinguishing feature of Wenzhou Jixing Metal Materials Co., Ltd.'s quality assurance program is the adoption of a Novel Coil Tube Hole Inspection Method (新型盘管验孔技术). This proprietary inspection approach addresses the inherent challenges of verifying tube bore quality in continuous coil formats:
- Enhanced Efficiency: The new inspection methodology achieves a substantial increase in inspection throughput compared to traditional manual or random-sampling approaches, reducing production cycle time without compromising coverage.
- Comprehensive Coverage: Unlike sampling-based inspection, the novel method enables near-100% bore verification along the coil length, ensuring that internal defects such as seams, inclusions, laminations, and wall-thickness deviations are identified before shipment.
- Non-Destructive Testing Integration: The inspection process integrates ET (Eddy Current Testing), UT (Ultrasonic Testing), and optical bore profiling to provide multi-modal defect detection.
- Data Traceability: Inspection results are digitally recorded and linked to each coil's heat number, enabling full traceability from raw material to finished product.
- Standardized Protocol: The methodology has been formalized into an internal standard operating procedure, ensuring consistency and repeatability across production shifts.
6. Applications
Stainless steel coil tubes from Wenzhou Jixing Metal Materials Co., Ltd. serve a wide array of industrial sectors:
- Petrochemical & Oil/Gas: Heat exchangers, condensers, reactor internals, process piping, and offshore platforms
- Food & Beverage Processing: Hygienic piping systems, brewing equipment, dairy processing lines, and pharmaceutical equipment
- Automotive & Transportation: Exhaust systems, fuel delivery lines, brake lines, and structural components
- Medical & Biotechnology: Surgical instrument tubing, dialysis equipment, laboratory apparatus
- Construction & Architecture: Structural supports, handrails, decorative cladding, and building frameworks
- Electronics & Energy: Solar thermal collectors, battery pack cooling tubes, heat sink assemblies
- Chemical Processing: Corrosive media transfer lines, storage tank internals, distillation columns
7. Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains the following certifications and complies with the following standards:
| Certification / Standard | Description |
|---|---|
| ISO 9001:2015 | Quality Management System certification ensuring consistent product quality and process control |
| ISO 14001:2015 | Environmental Management System certification |
| EN 10204 3.1 | European inspection certificate confirming conformity to specified requirements |
| EN 10204 3.2 | European inspection certificate based on test reports |
| Mill Test Certificates (MTC) | Provided with each shipment, detailing chemical composition, mechanical properties, and heat treatment records |
| ASTM / ASME Compliance | Product conforms to applicable ASTM and ASME (American Society of Mechanical Engineers) specifications |
| CE Marking | European conformity marking for products intended for the European Economic Area |
8. Packaging & Shipping
Coil tubes are packaged to ensure protection during storage and transportation:
- Each coil is wrapped in VCI-impregnated paper and sealed with moisture-absorbent desiccant bags
- Outer wrapping with PE (Polyethylene) film or kraft paper
- Coils are strapped with steel bands and placed on wooden or steel coil saddles
- Each coil is clearly labeled with product code, grade, dimensions, heat number, coil weight, and manufacturing date
- Customized packaging is available for export shipments to meet destination-country requirements
9. Technical Support & Customization
Wenzhou Jixing Metal Materials Co., Ltd. offers comprehensive technical support including:
- Material selection consultation based on application requirements
- Custom dimension and tolerance specifications
- Special surface finishes and post-processing (cutting, threading, bending, welding)
- Third-party inspection and testing arrangements
- On-site technical guidance for installation and fabrication
Company Commitment: Wenzhou Jixing Metal Materials Co., Ltd. is dedicated to delivering premium-quality stainless steel coil tubes backed by rigorous quality control, innovative inspection methodologies, and full traceability. The company's continuous investment in process improvement — exemplified by the adoption of the novel coil tube hole inspection technology — ensures that every product meets the highest standards of dimensional accuracy, material integrity, and performance reliability.