SDECR Series Stainless Steel Coil Tube Fan Coil Unit
Product Overview
The SDECR Series Fan Coil Unit is a precision-engineered HVAC terminal unit that integrates high-performance stainless steel coil tubes (Coiltube) as its core heat exchange component. Manufactured by Wenzhou Jixing Metal Materials Co., Ltd., this unit is designed to deliver superior thermal efficiency, exceptional corrosion resistance, and long-term operational reliability in both commercial and industrial air conditioning systems. The SDECR designation denotes a concealed (Ceiling-mounted), return-air (Return), and low-noise (Quiet) configuration optimized for embedded installation in suspended ceiling systems.
The product represents a significant advancement in fan coil unit design, leveraging the metallurgical advantages of austenitic stainless steel coil tubing to overcome the common limitations of traditional copper-aluminum heat exchangers, including susceptibility to galvanic corrosion, chemical degradation in aggressive environments, and limited service life in high-humidity or chemically contaminated air streams.
Material & Properties
The stainless steel coil tube component at the heart of the SDECR unit is fabricated from high-purity austenitic stainless steel, meeting or exceeding international material standards. The material composition and mechanical properties are as follows:
- Base Material: Austenitic Stainless Steel (奥氏体不锈钢), Grade 304 (UNS S30408) or Grade 316L (UNS S31603) for enhanced chloride resistance
- Carbon Content (C): ≤ 0.08% (Grade 304) / ≤ 0.03% (Grade 316L)
- Chromium Content (Cr): 18.0–20.0%
- Nickel Content (Ni): 8.0–10.5%
- Molybdenum Content (Mo): 2.0–3.0% (Grade 316L only)
- Tensile Strength (抗拉强度): ≥ 520 MPa (Grade 304) / ≥ 485 MPa (Grade 316L)
- Yield Strength (屈服强度): ≥ 205 MPa
- Elongation (延伸率): ≥ 40%
- Operating Temperature Range (工作温度范围): −196°C to +870°C
- Corrosion Resistance (耐腐蚀性): Excellent resistance to atmospheric corrosion, acidic environments, and chloride-containing media
- Thermal Conductivity (导热系数): 16.3 W/(m·K) at 20°C (Grade 304)
The stainless steel coil tube offers a significant advantage in Corrosion Resistance (耐腐蚀性能) compared to conventional carbon steel or copper tubing. The chromium-rich passive oxide layer (Cr₂O₃) that forms spontaneously on the surface provides a self-repairing barrier against oxidation and chemical attack, ensuring service life exceeding 25 years under normal operating conditions.
Technical Specifications
| Parameter (参数) | Specification (规格) |
|---|---|
| Product Model (产品型号) | SDECR Series (SDECR-100 / SDECR-150 / SDECR-200 / SDECR-300 / SDECR-400 / SDECR-500 / SDECR-600) |
| Installation Type (安装方式) | Ceiling Concealed (吊顶暗装) |
| Coil Tube Material (盘管材质) | Stainless Steel (不锈钢), Grade 304 or 316L |
| Coil Tube Diameter (盘管管径) | Φ7.0 mm / Φ9.52 mm / Φ12.0 mm |
| Tube Wall Thickness (管壁厚度) | 0.5 mm – 0.8 mm |
| Fins Material (翅片材质) | Aluminum Alloy (铝合金) or Stainless Steel (不锈钢), Hydrophilic Coated (亲水涂层) |
| Fin Spacing (翅片间距) | 1.8 mm – 2.5 mm |
| Number of Rows (排数) | 2-Row / 4-Row / 6-Row |
| Cooling Capacity (制冷量) | 2.8 kW – 14.0 kW |
| Heating Capacity (制热量) | 2.5 kW – 13.5 kW |
| Water Flow Rate (水流量) | 0.4 L/min – 2.0 L/min |
| Water Pressure Drop (水侧压降) | ≤ 0.15 MPa |
| Air Volume (风量) | 450 m³/h – 2,200 m³/h (Low / Medium / High Speed) |
| Noise Level (噪音水平) | 22 dB(A) – 38 dB(A) (Low Speed, 1 m distance) |
| Power Supply (电源) | 220V / 50Hz / Single Phase (单相) |
| Fan Motor (风机电机) | Brushless DC Motor (无刷直流电机) or AC Motor (交流电机) |
| Motor Power (电机功率) | 25W – 180W (depending on model) |
| Drainage Method (排水方式) | Gravity Drainage (重力排水) with Sloped Tray (倾斜水盘) |
| Condensate Tray (冷凝水盘) | Stainless Steel (不锈钢), Molded with Anti-Mold Coating (防霉涂层) |
| Operating Humidity (工作湿度) | ≤ 95% RH (Non-condensing) |
| Weight (重量) | 18 kg – 45 kg (depending on model) |
| Dimensions (外形尺寸) | 1,200 mm × 450 mm × 200 mm (standard, varies by model) |
Manufacturing Process
The production of the SDECR Series Fan Coil Unit follows a rigorous multi-stage manufacturing protocol designed to ensure dimensional accuracy, material integrity, and functional reliability:
- Raw Material Inspection (原材料检验): Incoming stainless steel coil stock is subjected to spectroscopic analysis (Spectrographic Analysis) to verify chemical composition compliance with ASTM A270 / ASTM A269 or GB/T 12771 standards. Each batch undergoes hardness testing, tensile testing, and visual surface inspection.
- Pipe Forming & Bending (管道成型与弯管): Stainless steel tubing is formed into serpentine coil configurations using precision CNC bending machines (CNC Bending Machine). Bend radii are controlled to prevent wall thinning (Wall Thinning) and ovality (椭圆度) exceeding 5% of the nominal diameter. Minimum bend radius is maintained at 3D (three times the tube diameter).
- Fins Attachment (翅片安装): Aluminum or stainless steel fins are mechanically bonded to the coil tubes through a slitting and crimping process (Slitting and Crimping Process). Fin-to-tube contact resistance is optimized to ensure maximum heat transfer efficiency (Heat Transfer Efficiency).
- Welding (焊接): Header connections (Header Connections) and inlet/outlet ports are fabricated using Argon Arc Welding (TIG Welding, Tungsten Inert Gas Welding) to produce leak-free, metallurgically sound joints. Weld quality is verified through visual inspection and helium leak testing (Helium Leak Testing) at a detection threshold of 1×10⁻⁹ Pa·m³/s.
- Hydrostatic Pressure Testing (水压试验): Each completed coil assembly undergoes hydrostatic pressure testing at 1.5 times the maximum operating pressure for a minimum duration of 30 minutes to confirm structural integrity and absence of micro-leaks.
- Assembly & Integration (总装与集成): The coil assembly is integrated with the fan motor, casing, condensate tray, and control components within a precision-formed galvanized steel or stainless steel housing. All components are aligned to minimize aerodynamic turbulence and vibration.
- Quality Control & Testing (质量控制与测试): Final units undergo comprehensive performance testing including air volume measurement (Air Volume Measurement), cooling/heating capacity verification (Capacity Verification), noise measurement (Noise Measurement) in an anechoic chamber (Anechoic Chamber), and electrical safety testing (Electrical Safety Testing) per IEC 60335 standards.
- Packaging & Shipping (包装与运输): Units are packaged with moisture-absorbing desiccants, protective foam padding, and corrosion-inhibiting wrapping to ensure damage-free delivery.
Applications
The SDECR Series Stainless Steel Coil Tube Fan Coil Unit is engineered for a broad spectrum of HVAC applications where durability, hygiene, and thermal performance are critical:
- Commercial Buildings (商业建筑): Office buildings, shopping malls, hotels, and retail spaces requiring concealed ceiling-mounted cooling and heating solutions.
- Healthcare Facilities (医疗设施): Hospitals, clinics, and pharmaceutical cleanrooms where corrosion resistance, antimicrobial properties, and low particulate emission are essential for maintaining sterile environments.
- Food Processing & Beverage Industries (食品加工与饮料行业): Facilities exposed to high humidity, acidic vapors, and cleaning chemicals where stainless steel coil tubes provide superior chemical resistance.
- Chemical & Petrochemical Plants (化工与石化厂): Industrial environments with aggressive atmospheric contaminants requiring maximum corrosion protection.
- Marine & Coastal Installations (海洋与沿海设施): Buildings located in high-salt-air environments where chloride-induced pitting corrosion (Pitting Corrosion) is a significant concern.
- Data Centers & Server Rooms (数据中心与机房): Facilities requiring precise temperature and humidity control with minimal maintenance downtime.
- Educational & Institutional Buildings (教育与机构建筑): Schools, universities, and government buildings requiring reliable, low-noise climate control.
- Residential High-Rise Buildings (住宅高层建筑): Premium residential projects where long-term durability and low maintenance are prioritized.
Quality Certifications & Standards Compliance
The SDECR Series Fan Coil Unit is manufactured in strict compliance with the following international and national standards, and has obtained the following quality certifications:
- ISO 9001:2015 — Quality Management System Certification (质量管理体系认证)
- ISO 14001:2015 — Environmental Management System Certification (环境管理体系认证)
- ISO 45001:2018 — Occupational Health and Safety Management System (职业健康安全管理体系)
- CE Marking (CE认证) — Conformity with European Directive 2006/95/EC (Low Voltage Directive) and 2014/35/EU
- UL Listed (UL认证) — Underwriters Laboratories Safety Certification for North American markets
- GB/T 19232 — Chinese National Standard for Air-Conditioning Fan Coil Units (空调用风机盘管机组)
- GB/T 12771 — Chinese National Standard for Welded Stainless Steel Tubes (焊接不锈钢管)
- ASTM A270 / ASTM A269 — American Society for Testing and Materials Standards for Stainless Steel Tube
- EN 10217 — European Standard for Stainless Steel Tubes
- RoHS Compliance (RoHS合规) — Restriction of Hazardous Substances Directive 2011/65/EU
- Energy Efficiency (能效等级): Compliant with GB 19576 Energy Efficiency Standard, achieving Grade 2 or higher energy efficiency rating
Unique Selling Points
The SDECR Series distinguishes itself from conventional fan coil units through the following key advantages:
- Superior Corrosion Resistance (卓越耐腐蚀性): The use of Grade 304 or 316L stainless steel coil tubes eliminates the risk of rust formation, galvanic corrosion, and chemical degradation, extending service life to over 25 years — significantly exceeding the typical 8–12 year lifespan of copper-aluminum heat exchangers.
- Hygienic & Food-Grade Compatibility (卫生级与食品级兼容性): Stainless steel coil tubes are inherently non-toxic, non-porous, and resistant to microbial growth, making the SDECR unit ideal for healthcare and food processing applications where hygiene standards are stringent.
- Low Maintenance (低维护需求): The corrosion-resistant coil tube requires no protective coatings, anti-corrosion treatments, or periodic replacement, reducing total cost of ownership (Total Cost of Ownership, TCO) by an estimated 30–40% over the unit's lifecycle.
- Low Noise Operation (低噪音运行): Optimized aerodynamic design of the fan impeller and casing achieves noise levels as low as 22 dB(A) at low speed, ensuring acoustic comfort in sensitive environments such as hospitals, libraries, and executive offices.
- High Thermal Efficiency (高换热效率): Precision-engineered coil tube geometry with optimized fin spacing and tube-to-fin bonding maximizes heat transfer coefficient (Heat Transfer Coefficient), achieving COP (Coefficient of Performance) values that exceed industry benchmarks.
- Wide Operating Temperature Range (宽工作温度范围): The stainless steel coil tube maintains mechanical integrity and thermal performance across an extreme temperature range of −196°C to +870°C, enabling reliable operation in diverse climatic conditions.
- Environmentally Friendly (环保特性): Stainless steel is 100% recyclable with no loss of material properties, supporting sustainable manufacturing practices and circular economy (Circular Economy) principles.