Stainless Steel Coil Tube (Coiltube) — Ice Storage Thermal Management Application
Product Overview
The Stainless Steel Coil Tube (Coiltube) is a precision-engineered tubular product manufactured by Wenzhou Jixing Metal Materials Co., Ltd. (Product No. 1064). Designed for advanced thermal management systems, this coil tube is specifically engineered for use in thermal-conductive plastic coil tube ice storage tanks, where it serves as the primary heat exchange medium for external ice-melting cooling dynamic systems. The product leverages the superior thermal conductivity, corrosion resistance, and mechanical integrity of austenitic stainless steel to deliver efficient latent heat transfer in ice-based thermal energy storage (TES) applications.
The coil tube is wound into a continuous helical configuration, maximizing the surface area-to-volume ratio for optimal heat exchange efficiency. This geometry is critical in dynamic ice-melting cooling systems where rapid and uniform heat absorption from the surrounding medium is required to maintain stable thermal cycling performance.
Material & Properties
The coil tube is fabricated from high-purity austenitic stainless steel, selected for its exceptional combination of thermal conductivity, mechanical strength, and long-term corrosion resistance in aqueous and chemical environments.
- Material Grade: SUS304 / SUS316L (ASTM A213 TP304 / TP316L)
- Thermal Conductivity: 14–16 W/(m·K) at 20°C — providing efficient heat transfer for ice-melting applications
- Corrosion Resistance: Excellent resistance to pitting, crevice corrosion, and stress corrosion cracking in chloride-containing environments
- Operating Temperature Range: −196°C to +870°C (SUS304); −270°C to +450°C (SUS316L in high-chloride environments)
- Surface Finish: Electropolished or pickled & passivated, achieving Ra ≤ 0.4 μm for reduced fouling and enhanced heat transfer
- Mechanical Properties: Tensile Strength ≥ 515 MPa; Yield Strength ≥ 205 MPa; Elongation ≥ 40%
Specifications
| Parameter | Specification | Standard / Reference |
|---|---|---|
| Product Name | Stainless Steel Coil Tube (Coiltube) | — |
| Product No. | 1064 | — |
| Material | SUS304 / SUS316L (Austenitic Stainless Steel) | ASTM A213 / GB/T 12771 |
| Outer Diameter (OD) | Φ6.0 mm – Φ25.4 mm (customizable) | GB/T 12771 |
| Wall Thickness | 0.5 mm – 2.0 mm (customizable) | GB/T 12771 |
| Coil Winding Diameter | Φ100 mm – Φ600 mm (application-dependent) | — |
| Coil Length (per unit) | 10 m – 100 m (continuous coiling) | — |
| Surface Treatment | Electropolished / Pickled & Passivated | GB/T 14323 |
| Pressure Rating | Up to 1.6 MPa (PN16) | EN 10217 |
| Winding Tolerance | ±0.5 mm pitch accuracy | — |
| Application Environment | Ice storage / Thermal energy storage / Chilled water systems | — |
| Standards Compliance | ASTM A213, GB/T 12771, EN 10217, ISO 6509 | — |
Manufacturing Process
The production of the Stainless Steel Coil Tube follows a rigorous multi-stage manufacturing process to ensure dimensional accuracy, mechanical integrity, and surface quality:
- Raw Material Selection: High-purity austenitic stainless steel strip or seamless tube blanks are sourced from certified mills, with full chemical composition verification (PMI — Positive Material Identification) and mechanical property testing.
- Seamless Tube Drawing / Cold Drawing: Seamless tubes are cold-drawn through precision dies to achieve the required outer diameter and wall thickness tolerances, ensuring uniform microstructure and mechanical properties.
- Heat Treatment (Solution Annealing): Tubes are solution-annealed at 1050–1100°C followed by controlled cooling to eliminate residual stresses, restore full austenitic structure, and ensure optimal corrosion resistance.
- Precision Coiling: The annealed tubes are fed through a CNC-controlled coiling machine, wound into the specified helical geometry with tight pitch tolerance (±0.5 mm). The coiling process is designed to avoid kinking, ovality, or plastic deformation of the tube cross-section.
- Surface Finishing: Tubes undergo pickling and passivation (or electropolishing) to remove surface oxides, contaminants, and to form a protective chromium oxide passive layer, critical for long-term corrosion resistance in aqueous environments.
- Quality Inspection: Each coil undergoes hydrostatic pressure testing, dimensional verification (OD, wall thickness, coil diameter), visual surface inspection, and magnetic particle testing (for crack detection). Spectroscopic analysis (OES/XRF) confirms material composition.
- Packaging & Delivery: Coils are wrapped in protective film, packed in wooden crates or custom containers to prevent mechanical damage and moisture exposure during transit.
Applications
The Stainless Steel Coil Tube is engineered for demanding thermal management applications, with primary use cases including:
- Ice Storage Thermal Energy Storage (TES) Systems: Serves as the heat exchange coil within thermal-conductive plastic ice storage tanks, enabling external ice-melting cooling dynamic operation. The coil absorbs latent heat from the ice mass during the melting cycle, providing efficient and stable cooling output.
- Chilled Water Distribution Systems: Utilized in commercial and industrial HVAC (Heating, Ventilation, and Air Conditioning) systems where stainless steel's corrosion resistance is critical for long-term reliability in water-based heat transfer loops.
- Process Cooling in Chemical & Pharmaceutical Industries: Employed in heat exchangers and cooling circuits where hygiene, corrosion resistance, and thermal efficiency are paramount.
- Low-Temperature Applications: Suitable for cryogenic and sub-zero thermal systems where stainless steel maintains ductility and structural integrity at temperatures well below the freezing point.
- Marine & Offshore Cooling Systems: The SUS316L grade provides superior resistance to chloride-induced pitting corrosion, making it ideal for marine environments.
Quality Certifications & Standards Compliance
Wenzhou Jixing Metal Materials Co., Ltd. adheres to internationally recognized quality management and product standards to ensure consistent performance and traceability:
- ISO 9001:2015 — Quality Management System Certification
- ISO 14001:2015 — Environmental Management System Certification
- ASTM A213 — Specification for Seamless Ferritic, Austenitic, and Ferritic-Austenitic Alloy-Steel Tubing for High Temperature and High Pressure Boilers and Heat Exchangers
- GB/T 12771 — Technical Specification for Stainless Steel Seamless Tubes for General Purpose
- EN 10217 — Technical Delivery Conditions for Stainless Steel Tubes for Pressure Purposes
- ISO 6509 — Welded Stainless Steel Tubes for General Purposes
- GB/T 14323 — Pickling and Passivation of Stainless Steel
All products are accompanied by Mill Test Certificates (MTC) and Third-Party Inspection Reports (available upon request) providing full chemical composition, mechanical property data, and dimensional verification results.
Unique Selling Points
The Stainless Steel Coil Tube (No. 1064) from Wenzhou Jixing Metal Materials Co., Ltd. distinguishes itself through:
- Superior Thermal Performance: Optimized helical geometry maximizes heat transfer surface area, enabling rapid and uniform ice-melting cooling in dynamic thermal energy storage systems.
- Exceptional Corrosion Resistance: Austenitic stainless steel construction ensures decades of service life even in aggressive aqueous and chemical environments, eliminating the need for costly replacements or coatings.
- Precision Coiling Tolerance: CNC-controlled winding ensures dimensional accuracy of ±0.5 mm pitch, guaranteeing seamless integration into pre-designed tank and system configurations.
- Full Traceability & Compliance: Complete material traceability from raw steel mill to finished product, with adherence to ASTM, GB, EN, and ISO international standards.
- Customization Capability: Flexible range of diameters, wall thicknesses, coil configurations, and material grades (SUS304/SUS316L) to meet specific application requirements.
- Electropolished Surface Finish: Ultra-smooth surface (Ra ≤ 0.4 μm) reduces fouling, minimizes flow resistance, and enhances overall thermal efficiency in ice storage cooling systems.