Stainless Steel Coil Tube (Coiltube) — Product Technical Specification
Manufacturer: Wenzhou Jixing Metal Materials Co., Ltd.
Product Series: Coiltube (盘管)
Product Reference No.: 959
1. Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. manufactures high-performance Stainless Steel Coil Tubes (盘管, Coiltube), designed for demanding fluid transfer, heat exchange, and pneumatic applications. These coil tubes are supplied in continuous coil form, enabling seamless integration into automated manufacturing lines, HVAC systems, refrigeration units, and industrial fluid conveyance networks. The product is engineered to meet the rigorous standards required for five-star hotel building services (HVAC), pharmaceutical processing, food-grade piping, and chemical transport systems.
Coiltube products offer the distinct advantage of continuous, joint-free length, minimizing leak points and reducing installation labor compared to straight-segment pipe assemblies. The coil configuration also facilitates compact storage, efficient transport logistics, and on-site deployment through spring-back or hydraulic forming techniques.
2. Material & Properties
2.1 Material Grades
- Austenitic Stainless Steel: SUS304 (UNS S30400), SUS316L (UNS S31603), SUS321 (UNS S32100)
- Super-Austenitic Grades: SUS904L (UNS N08904), SUS2205 Duplex (UNS S31803) — available upon request
- Other Custom Grades: Available per ASTM, EN, or JIS specifications
2.2 Key Mechanical & Physical Properties (Typical — SUS304)
- Tensile Strength: ≥ 520 MPa (75,000 psi)
- Yield Strength (0.2% offset): ≥ 205 MPa (29,700 psi)
- Elongation (A50): ≥ 40%
- Density: 8.0 g/cm³
- Thermal Conductivity: 16.3 W/(m·K) at 100°C
- Operating Temperature Range: −196°C to +870°C (−321°F to +1,598°F)
- Corrosion Resistance: Excellent resistance to atmospheric corrosion, weak acids, and alkaline solutions; SUS316L grade provides superior resistance to chlorides and marine environments
2.3 Surface Finish Options
- 2B Mill Finish: Standard cold-rolled and annealed finish
- BA (Bright Annealed): Smooth, reflective surface suitable for food-grade and pharmaceutical applications
- Electropolished: Ra ≤ 0.25 μm, compliant with sanitary piping standards
- Passivated: Chemical passivation treatment per ASTM A967
- Custom Surface: Available upon specification
3. Specifications
| Parameter | Specification Range | Standard / Reference |
|---|---|---|
| Outer Diameter (OD) | Φ 3.0 mm – Φ 108.0 mm (Φ 1/8" – Φ 4") | ASTM A554 / A269, EN 10217, JIS G3459 |
| Wall Thickness (WT) | 0.30 mm – 6.00 mm | As per customer specification |
| Coil Inner Diameter (ID) | Φ 200 mm – Φ 1,000 mm | Customizable |
| Coil Length | Continuous coil; typical 50 m – 500 m per coil | Per order requirement |
| OD Tolerance | ± 0.05 mm (precision grade); ± 0.10 mm (standard grade) | ASTM A554 |
| WT Tolerance | ± 10% of nominal wall thickness | ASTM A554 |
| Pressure Rating | Up to 30 MPa (4,350 psi) depending on OD/WT combination | Calculated per ASME B31.3 |
| Sanitary Grade | Compliant with 3-A Sanitary Standards; FDA 21 CFR compliant | 3-A / FDA / EHEDG |
| End Treatment | Plain, beveled, threaded, or flanged (custom) | Per customer drawing |
| Material Certificates | Mill Test Certificate (MTC) EN 10204 3.1 / 3.2 | EN 10204 |
4. Manufacturing Process
Wenzhou Jixing Metal Materials Co., Ltd. employs a fully integrated manufacturing process to ensure dimensional accuracy, metallurgical integrity, and surface quality:
- Raw Material Sourcing: Virgin stainless steel strip procured from certified mill sources (e.g., POSCO, Outokumpu, Taiyuan Stainless Steel) with full traceability documentation.
- Strip Inspection & Pre-treatment: Incoming strip undergoes visual inspection, thickness gauging, and surface cleanliness verification. Any surface defects are removed via mechanical or chemical cleaning.
- Cold Roll Forming / Hydraulic Bending: The strip is formed into seamless tube sections using precision cold-drawing or hydraulic bending machinery. This ensures uniform wall thickness and tight dimensional tolerances without heat-affected zones (HAZ).
- Welding (for welded coil tube): Where applicable, continuous TIG (Tungsten Inert Gas) welding or orbital welding is performed under controlled shielding gas (Argon) atmosphere to produce a smooth, burr-free weld seam.
- Coil Winding: The formed tube is wound onto precision-guided spools to create the coil configuration, with controlled tension to prevent deformation or kinking.
- Heat Treatment / Annealing: Solution annealing at 1,050°C – 1,150°C followed by controlled cooling to eliminate residual stresses and restore full austenitic microstructure.
- Pickling & Passivation: The tube is treated with a mixed acid solution (HNO₃/HF) to remove scale, followed by nitric acid passivation to establish a protective chromium oxide layer.
- Surface Finishing: Optional electropolishing, mechanical polishing, or brushing to achieve specified surface roughness (Ra values).
- Quality Inspection: Each coil undergoes hydrostatic pressure testing, dimensional verification (OD, WT, roundness), visual inspection, and, if required, eddy current testing or X-ray radiography.
- Coating & Packaging: The coil is wrapped in moisture-proof protective film, placed in wooden or steel crates, and labeled with product identification, material grade, heat number, and quantity.
5. Applications
Stainless steel coil tubes from Wenzhou Jixing Metal Materials Co., Ltd. serve a wide range of industrial and commercial sectors:
- HVAC Systems (Heating, Ventilation & Air Conditioning): Coil tubes are integral to fan coil units (FCU), air handling units (AHU), and heat exchangers in five-star hotels, commercial buildings, and data centers. The continuous coil form reduces joint count and enhances thermal efficiency in refrigerant circuit design.
- Refrigeration & Air Conditioning: Used as evaporator and condenser coils in commercial refrigeration systems, automotive AC condensers, and industrial chiller units.
- Food & Beverage Processing: Sanitary-grade coil tubes (BA or electropolished finish) are used in dairy processing, brewing, beverage carbonation, and CIP (Clean-in-Place) systems. Compliant with 3-A, FDA, and EHEDG standards.
- Pharmaceutical Manufacturing: High-purity SUS316L coil tubes used in process piping, steam sterilization loops, and GMP-compliant production lines.
- Chemical & Petrochemical Industry: Resistant to aggressive chemicals, acids, and high-temperature service. SUS316L and duplex grades suitable for chlorinated environments.
- Automotive & Transportation: Fuel lines, brake lines, exhaust systems, and hydrogen fuel cell cooling circuits.
- Medical Devices: Endoscope tubing, infusion line components, and surgical instrument tubing requiring biocompatibility and sterilizability.
- Pneumatic & Hydraulic Systems: Air and hydraulic fluid conveyance in industrial automation, robotics, and heavy machinery.
- Solar Thermal & Geothermal Systems: Heat collector tubes and geothermal well casing due to corrosion resistance and thermal cycling durability.
6. Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains rigorous quality management and holds the following certifications and complies with the following international standards:
| Certification / Standard | Description |
|---|---|
| ISO 9001:2015 | Quality Management System — certified for design, manufacturing, and supply of stainless steel products |
| ISO 14001:2015 | Environmental Management System — demonstrating commitment to sustainable manufacturing practices |
| ISO 45001:2018 | Occupational Health & Safety Management System |
| EN 10204 3.1 / 3.2 | Material Test Certificates — full chemical analysis, mechanical test reports, and traceability documentation |
| CE Marking (EU) | Compliant with European Pressure Equipment Directive (PED) 2014/68/EU for pressure-containing applications |
| ASME / NB (USA) | Available for products intended for use in pressure vessels and piping per ASME Boiler and Pressure Vessel Code |
| 3-A Sanitary Standards | For food-grade applications, ensuring hygienic design and cleanability |
| NSF / ANSI 61 | Drinking water system components compliance (where applicable) |
7. Unique Selling Points
- Joint-Free Continuous Length: The coil configuration eliminates field welding, reducing leak risk and installation time by up to 40% compared to straight-segment assemblies.
- Precision Dimensional Control: Advanced cold-forming and hydraulic bending technology ensures OD tolerance of ± 0.05 mm and WT tolerance of ± 10%, critical for heat exchanger and sanitary applications.
- Full Material Traceability: Every coil is accompanied by a mill test certificate (MTC) with complete chemical composition, mechanical properties, and heat-number traceability back to the original steel mill.
- Multi-Grade Flexibility: Availability of standard austenitic (304, 316L), super-austenitic (904L), and duplex (2205) grades allows customers to optimize material selection for specific corrosion, temperature, and pressure requirements.
- Sanitary-Grade Surface Quality: Electropolished finish achieving Ra ≤ 0.25 μm meets the most stringent pharmaceutical and food-industry hygiene requirements without post-fabrication finishing.
- Custom Engineering Support: Wenzhou Jixing offers OEM/ODM services with custom OD, WT, coil diameter, end treatment, and surface finish tailored to customer specifications and application requirements.
- Cost-Efficient Logistics: Coil packaging maximizes volumetric efficiency, reducing shipping costs and storage footprint for bulk orders.
- HVAC-Optimized Design: Coil tubes are specifically engineered for use in fan coil units and fresh air systems, providing superior thermal performance and long-term reliability in commercial and hospitality building services.
8. Ordering Information
Customers are advised to provide the following information when placing an order:
- Material grade (e.g., SUS304, SUS316L)
- Outer diameter (OD) and wall thickness (WT) — nominal dimensions
- Required coil inner diameter (ID) and approximate coil length
- Surface finish requirement (2B, BA, Electropolished, Passivated)
- End treatment (Plain, Beveled, Threaded, Flanged)
- Applicable standard (ASTM, EN, JIS, GB/T, or custom)
- Quantity (number of coils or total length)
- Required certifications (MTC 3.1, 3.2, CE, ASME, 3-A, etc.)
- Intended application and operating conditions (temperature, pressure, medium)
Note: All product specifications are subject to the final approved customer drawing or purchase order. Wenzhou Jixing Metal Materials Co., Ltd. reserves the right to modify specifications with prior customer notification. For detailed technical data sheets, material certifications, and custom quotation, please contact the manufacturer directly.