Stainless Steel Coil Tube (Fan Coil Unit Heat Exchanger Series)
Product Overview
The Stainless Steel Coil Tube (Coiltube) manufactured by Wenzhou Jixing Metal Materials Co., Ltd. is a precision-engineered tubular component designed specifically for integration into fan coil unit (FCU) heat exchanger systems. This product is engineered in accordance with advanced dynamic heat transfer modeling principles and computer simulation optimization, ensuring superior thermal performance, mechanical integrity, and long-term operational reliability in HVAC (Heating, Ventilation, and Air Conditioning) applications.
Unlike conventional straight-tube heat exchanger assemblies, the coil tube configuration maximizes the effective heat transfer surface area within a compact footprint, enabling high-efficiency thermal exchange between working fluids and ambient air streams. The product line is developed with reference to validated computational fluid dynamics (CFD) simulations and transient thermal analysis models, which inform optimal coil geometry, tube diameter selection, and pitch configurations.
Material & Properties
The coil tubes are fabricated from high-grade austenitic stainless steel, selected for its exceptional corrosion resistance, thermal conductivity, and mechanical durability under cyclic thermal loading conditions.
- Primary Alloy Grades: SUS304 (UNS S30400), SUS316 (UNS S31600), SUS316L (UNS S31603)
- Corrosion Resistance: Superior resistance to chloride-induced pitting and crevice corrosion, particularly in marine and humid environments (SUS316L)
- Thermal Conductivity: 14.9–16.3 W/(m·K) at 20°C, providing efficient heat transfer performance
- Operating Temperature Range: −196°C to +870°C (depending on alloy grade)
- Non-magnetic: Naturally non-magnetic in annealed condition, suitable for sensitive electronic environments
- Hygienic Surface: Passivated surface finish with Ra ≤ 0.4 μm, compliant with sanitary standards
Specifications
| Parameter | Specification |
|---|---|
| Product Name | Stainless Steel Coil Tube (Coiltube) — Fan Coil Unit Heat Exchanger |
| Product Code | JX-CT-1218 |
| Tube Outer Diameter (OD) | 6.35 mm (1/4"), 9.52 mm (3/8"), 12.7 mm (1/2") |
| Tube Wall Thickness | 0.5 mm – 1.0 mm (customizable) |
| Coil Diameter | 50 mm – 200 mm (adjustable per design requirement) |
| Tube Pitch (Longitudinal) | 10 mm – 25 mm |
| Row Spacing | 12 mm – 30 mm |
| Material Grade | SUS304 / SUS316 / SUS316L |
| Surface Finish | Mill finish, electropolished, or passivated (Ra ≤ 0.4 μm) |
| Maximum Operating Pressure | 1.6 MPa (standard); 2.5 MPa (reinforced) |
| Heat Transfer Coefficient | ≥ 85 W/(m²·K) (air-side, optimized configuration) |
| Compliance Standards | ASTM A213, ASTM A269, GB/T 12771, EN 10217 |
| Customization | Available — dimensions, coil geometry, and material grade per customer specification |
Manufacturing Process
The production of Wenzhou Jixing Metal Materials' coil tubes follows a rigorous multi-stage manufacturing protocol, integrating computational design optimization with precision fabrication techniques:
- Computational Modeling & Design Optimization: Prior to fabrication, dynamic heat transfer models are developed using validated computer simulation software. Transient thermal analysis and CFD (Computational Fluid Dynamics) simulations determine optimal coil geometry, tube layout, and flow channel configurations to maximize heat exchange efficiency while minimizing pressure drop.
- Raw Material Selection & Inspection: Certified stainless steel wire rod is sourced from accredited suppliers. Incoming material undergoes spectroscopic analysis, tensile testing, and hardness verification to confirm compliance with specified alloy composition and mechanical properties.
- Precision Drawing & Forming: The stainless steel tube is cold-drawn to achieve exact dimensional tolerances (±0.05 mm on OD). Continuous coil forming is performed using CNC-controlled bending machinery to produce uniform coil geometry with consistent curvature radii.
- Welding & Brazing: U-bends and header connections are fabricated using TIG (Tungsten Inert Gas) welding or high-purity silver brazing. Weld joints undergo helium leak testing at 10⁻⁶ mbar·L/s sensitivity to ensure hermetic sealing.
- Surface Treatment & Passivation: The finished coil tube assembly undergoes acid pickling and passivation to remove oxide layers and form a protective chromium oxide film, enhancing long-term corrosion resistance.
- Quality Control & Performance Testing: Each batch undergoes dimensional verification (CMM inspection), pressure testing at 1.5× working pressure, and thermal performance validation against simulation predictions.
Applications
The Stainless Steel Coil Tube (Coiltube) is engineered for deployment in demanding thermal management applications, including:
- Fan Coil Units (FCU): Primary heat exchanger component in commercial and residential HVAC systems for precise temperature regulation
- Industrial Process Cooling: Heat dissipation in chemical processing, pharmaceutical manufacturing, and food processing plants
- Marine & Offshore Systems: Corrosion-resistant heat exchange in seawater-cooled applications
- Cleanroom HVAC: Hygienic air handling in semiconductor fabrication, biotechnology, and hospital environments
- Data Center Thermal Management: High-efficiency cooling coils for server room air conditioning
- Automotive & Transportation: Compact heat exchangers in HVAC systems for commercial vehicles and rail transport
Quality Certifications & Standards Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains comprehensive quality management systems ensuring traceability, consistency, and regulatory compliance:
- ISO 9001:2015 — Quality Management System certification
- ISO 14001:2015 — Environmental Management System certification
- ISO 45001:2018 — Occupational Health and Safety Management System
- CE Marking — European Conformity for pressure equipment and HVAC components
- ASTM / ASME Compliance — Material and fabrication standards (ASTM A213, A269; ASME B31.3)
- National Standards (China): GB/T 12771, GB/T 14976, GB 50242
- Full Material Traceability: Each coil tube batch is accompanied by a mill test certificate (MTC) and heat number documentation
Unique Selling Points
Simulation-Driven Design: Unlike conventional coil tube manufacturers, Wenzhou Jixing Metal Materials employs validated dynamic heat transfer modeling and computer simulation to optimize every coil geometry, resulting in demonstrably superior thermal performance (up to 15–20% improvement in heat transfer coefficient versus standard designs).
Precision Engineering: CNC-controlled manufacturing ensures dimensional accuracy of ±0.05 mm, guaranteeing seamless integration with existing fan coil unit assemblies and minimal field installation adjustments.
Full Customization Capability: Coil diameter, tube pitch, row spacing, material grade, and surface finish are all customizable to match specific thermal load requirements and installation constraints.
End-to-End Quality Assurance: From raw material spectroscopic verification through final thermal performance testing, every production stage is documented and traceable, ensuring consistent product quality across all batches.