FP-5 Stainless Steel Coil Tube — Fan Coil Unit Heat Exchanger Tube
1. Product Overview
The FP-5 Stainless Steel Coil Tube is a precision-engineered coil tube product developed by Wenzhou Jixing Metal Materials Co., Ltd., specifically designed for integration into the FP-5 type fan coil unit (FP—5型风机盘管机组). This coil tube serves as a critical heat exchange element within HVAC (Heating, Ventilation, and Air Conditioning) systems, providing efficient thermal transfer between circulating fluid media and ambient air streams.
The product represents a significant advancement in coil tube metallurgy and fabrication, combining the corrosion resistance and mechanical integrity of stainless steel with optimized geometric configurations for maximum heat transfer surface area per unit volume. The FP-5 series coil tube has been validated through rigorous development testing as documented in the official FP-5 Type Fan Coil Unit Development Report.
2. Material & Properties
2.1 Base Material
- Material Grade: Austenitic stainless steel conforming to GB/T 14976, ASTM A312, or EN 10217-7 standards
- Typical Composition:
- Chromium (Cr): 18.0–20.0%
- Nickel (Ni): 8.0–10.5%
- Molybdenum (Mo): ≤ 2.0% (for enhanced pitting resistance)
- Carbon (C): ≤ 0.08%
- Iron (Fe): Balance
- Corrosion Resistance: Excellent resistance to atmospheric corrosion, acidic condensate, and chlorinated cooling water environments
- Mechanical Properties: Tensile strength (Rm) ≥ 520 MPa; Yield strength (Rp0.2) ≥ 205 MPa; Elongation (A5) ≥ 40%
- Thermal Conductivity: 14.2–16.3 W/(m·K) at 20°C
- Operating Temperature Range: −196°C to +400°C
2.2 Surface Treatment
- Internal bore: Mirror-polished finish (Ra ≤ 0.4 μm) to minimize flow resistance
- External surface: Passivated and optionally coated with hydrophilic enhancement layer for improved condensation heat transfer
3. Technical Specifications
| Parameter | Specification | Standard / Reference |
|---|---|---|
| Product Model | FP-5 Coil Tube Series | — |
| Outer Diameter (OD) | Ø 9.52 mm / Ø 12.70 mm (standard options) | ASTM B730 |
| Wall Thickness (WT) | 0.65 mm / 0.81 mm / 1.00 mm | GB/T 14976 |
| Coil Pitch | 14.0 – 25.0 mm (adjustable per application) | — |
| Tube Length (Straight Segment) | 300 mm – 2,000 mm | — |
| Coil Diameter | 150 mm – 600 mm | — |
| Number of Rows | 1 to 6 rows (configurable) | — |
| Maximum Working Pressure | 1.6 MPa (design) / 2.4 MPa (test) | GB/T 17149 |
| Rated Cooling Capacity | Up to 5.2 kW (per unit, FP-5 configuration) | GB/T 19232 |
| Rated Heating Capacity | Up to 6.8 kW (per unit, FP-5 configuration) | GB/T 19232 |
| Flow Velocity (Water Side) | 0.8 – 2.5 m/s | — |
| Acoustic Performance | ≤ 28 dB(A) at 3 m distance | GB/T 19232 |
| Service Life | ≥ 15 years (under normal operating conditions) | — |
4. Manufacturing Process
4.1 Process Flow
- Raw Material Inspection: Incoming stainless steel strip/tube is verified for chemical composition (via optical emission spectroscopy), mechanical properties, and surface quality per ISO 9001 incoming inspection protocols.
- Coil Forming: Precision cold-bending or hydraulic coiling process using CNC-controlled mandrel systems to achieve uniform coil geometry with controlled springback compensation.
- Welding: TIG (Tungsten Inert Gas) welding or orbital welding for header connections; seam welds achieve full penetration with minimal heat-affected zone (HAZ) distortion.
- Hydrostatic Pressure Testing: Each coil tube assembly is pressure-tested at 1.5× the maximum working pressure for a minimum dwell time of 30 seconds to ensure leak-tight integrity.
- Surface Passivation: Acid pickling and passivation treatment (per ASTM A967) to restore the full chromium oxide passive layer after welding operations.
- Dimensional Inspection: Coordinate measuring machine (CMM) verification of coil pitch, OD tolerance (±0.05 mm), and overall assembly dimensions.
- Final Assembly & Performance Testing: Integration into the FP-5 fan coil unit housing; air-side and water-side performance verification under standardized conditions (ASHRAE 16).
4.2 Key Process Controls
- Springback compensation algorithms implemented in CNC coiling software
- In-line laser diameter monitoring with real-time feedback control
- Weld seam radiography (X-ray) sampling at 5% rate for critical joints
- Full traceability from raw material heat number to finished product serial number
5. Applications
5.1 Primary Applications
- Commercial HVAC Systems: Fan coil units for office buildings, hotels, hospitals, and retail spaces requiring zone-level temperature control
- Residential Climate Control: Concealed and exposed fan coil units in high-end residential installations
- Industrial Process Cooling: Precision temperature control in electronics manufacturing, pharmaceutical production, and laboratory environments
- Light Industrial Heating: Radiant heating applications where stainless steel durability is required
5.2 FP-5 Fan Coil Unit Integration
The FP-5 series coil tube is specifically engineered for the FP-5 Type Fan Coil Unit, which is a concealed ceiling-mounted unit designed for medium-to-large commercial spaces. Key integration features include:
- Modular coil bank design allowing field-level capacity adjustment
- Compact footprint optimized for standard ceiling plenum dimensions
- Compatibility with both hydronic (water-to-air) and chilled water systems
- Support for variable refrigerant flow (VRF) interface configurations
6. Quality Certifications & Standards Compliance
6.1 Quality Management System
- ISO 9001:2015 — Quality Management System certification for manufacturing and supply chain
- ISO 14001:2015 — Environmental Management System
- ISO 45001:2018 — Occupational Health and Safety Management System
6.2 Product & Material Certifications
- CE Marking — Compliance with EU Pressure Equipment Directive (PED 2014/68/EU)
- GB/T 19232 — Chinese national standard for fan coil units (performance rating)
- GB/T 17149 — Chinese national standard for heat exchangers
- ASTM A312 / A213 — Seamless and welded austenitic stainless steel tubing
- EN 10217-7 — European standard for stainless steel tubes for heat exchangers
- UL / CSA — Safety certification for HVAC equipment (where applicable)
6.3 Testing & Verification
- Third-party performance testing by accredited laboratories (CNAS-accredited)
- Accelerated corrosion testing (salt spray per ASTM B117, 1,000+ hours without significant degradation)
- Cyclic fatigue testing per GB/T 17149 requirements (≥ 10,000 thermal cycles)
- Dimensional accuracy verified via independent metrology services
7. Unique Selling Points
- Superior Corrosion Resistance: The austenitic stainless steel construction eliminates the risk of internal corrosion and scale buildup common in carbon steel alternatives, ensuring consistent thermal performance over the service life
- Precision Coil Geometry: CNC-controlled coiling ensures uniform pitch and alignment, maximizing air-side heat transfer efficiency while minimizing pressure drop
- FP-5 System Optimization: Designed specifically for the FP-5 fan coil unit platform with validated performance data from the official development report
- Full Traceability: Complete material traceability from mill certificate to final product, supporting compliance audits in regulated industries
- Extended Service Life: Minimum 15-year design life with no degradation in thermal performance, offering superior total cost of ownership compared to conventional materials
- Environmental Sustainability: Stainless steel is 100% recyclable; the product supports LEED and green building certification requirements
8. Ordering Information
For detailed quotations, dimensional drawings, or custom configuration requests, contact Wenzhou Jixing Metal Materials Co., Ltd. with the following information:
- Required coil tube OD and wall thickness
- Coil pitch and number of rows
- Target cooling/heating capacity (kW)
- Operating fluid type and temperature range
- Required certifications and standards
- Quantity and delivery timeline
Wenzhou Jixing Metal Materials Co., Ltd. — Committed to excellence in stainless steel coil tube manufacturing, delivering engineered solutions that meet the highest international standards for the global HVAC and industrial process industries.