Stainless Steel Coil Tube (盘管) — Wenzhou Jixing Metal Materials Co., Ltd
Product Overview
The Stainless Steel Coil Tube (盘管, Coiltube) is a precision-engineered tubular product manufactured by Wenzhou Jixing Metal Materials Co., Ltd. This product is specifically designed for high-performance thermal management systems, including direct evaporation ice thermal storage systems (直接蒸发冰盘管蓄冷系统), HVAC heat exchangers, refrigeration units, and industrial heat transfer applications. The coil tube is formed through a continuous cold-forming process, producing a helically wound configuration that maximizes surface area within a compact footprint, thereby enhancing heat exchange efficiency.
The product designation Coiltube refers to a continuous stainless steel tube wound into a precise spiral or helical geometry, engineered to withstand extreme thermal cycling, corrosive media, and high-pressure operating conditions. Wenzhou Jixing Metal Materials Co., Ltd has accumulated extensive expertise in producing coil tubes tailored to the demanding requirements of thermal storage and refrigeration industries.
Material & Properties
The coil tube is manufactured from high-grade austenitic stainless steel, with the following material options available:
- AISI 304 (UNS S30408) — The most widely used grade, offering excellent general corrosion resistance, formability, and weldability. Ideal for HVAC and food-grade thermal applications.
- AISI 316 (UNS S31608) — Enhanced molybdenum content provides superior resistance to pitting and crevice corrosion, making it suitable for marine, chemical, and aggressive refrigerant environments.
- AISI 316L (UNS S31603) — Low-carbon variant of 316, optimized for welding applications where intergranular corrosion resistance is critical.
- AISI 321 (UNS S32108) — Titanium-stabilized grade offering excellent resistance to intergranular corrosion at elevated temperatures, suitable for high-temperature heat recovery systems.
Key Mechanical & Physical Properties
| Property | Specification |
|---|---|
| Tensile Strength (抗拉强度) | ≥ 515 MPa (AISI 304); ≥ 515 MPa (AISI 316) |
| Yield Strength (屈服强度) | ≥ 205 MPa (AISI 304); ≥ 170 MPa (AISI 316) |
| Elongation (延伸率) | ≥ 40% (AISI 304); ≥ 35% (AISI 316) |
| Density (密度) | 8.0 g/cm³ |
| Thermal Conductivity (导热系数) | 16.3 W/(m·K) at 100°C |
| Operating Temperature Range (工作温度范围) | −196°C to +870°C (AISI 304); −196°C to +870°C (AISI 316) |
| Maximum Working Pressure (最大工作压力) | Up to 4.0 MPa (depending on wall thickness) |
| Corrosion Resistance (耐腐蚀性) | Excellent resistance to atmospheric, acidic, and chlorinated environments |
Specifications
| Parameter | Specification / Range |
|---|---|
| Product Name | Stainless Steel Coil Tube (盘管, Coiltube) |
| Product Code | 1461 |
| Manufacturer | Wenzhou Jixing Metal Materials Co., Ltd |
| Outer Diameter (OD) (外径) | 3.0 mm – 50.8 mm (customizable) |
| Wall Thickness (壁厚) | 0.3 mm – 3.0 mm (customizable) |
| Coil Pitch (盘管节距) | 5.0 mm – 50.0 mm (adjustable per design requirements) |
| Coil Diameter (盘管直径) | 50 mm – 1000 mm (customizable) |
| Tube Length per Coil (单卷管长) | 10 m – 200 m (adjustable) |
| Surface Finish (表面光洁度) | No.4 Brushed, Mirror Polish (Ra ≤ 0.2 μm), or Passivated |
| End Treatment (端部处理) | Flat cut, Beveled, Threaded, or Flanged (per customer specification) |
| Applicable Standards (适用标准) | ASTM A213, ASTM A269, EN 10216-5, GB/T 12771, JIS G3459 |
| Packaging (包装) | Wooden crate / export-grade pallet with moisture-proof wrapping |
| Minimum Order Quantity (起订量) | Negotiable based on specification |
Manufacturing Process
The production of the stainless steel coil tube at Wenzhou Jixing Metal Materials Co., Ltd follows a rigorously controlled multi-stage manufacturing process:
- Raw Material Selection (原材料选型): Certified stainless steel seamless tubes or welded tubes conforming to ASTM/EN/GB standards are selected. Incoming material undergoes strict inspection for chemical composition (via XRF or optical emission spectroscopy) and mechanical properties.
- Cold Drawing & Sizing (冷拔与定径): Tubes are cold-drawn through precision dies to achieve exact outer diameter and wall thickness tolerances (±0.05 mm). This process enhances grain structure and surface finish.
- Solution Annealing (固溶退火): Tubes are solution-annealed at 1050°C – 1150°C followed by rapid quenching to ensure uniform microstructure, maximum corrosion resistance, and elimination of residual stresses from cold working.
- Coil Forming (盘管成型): The annealed tube is fed into a precision coil-forming machine equipped with CNC-controlled rollers. The tube is helically wound to the specified coil diameter, pitch, and length with high dimensional accuracy. The forming process maintains tube roundness and prevents ovalization or kinking.
- End Processing (端部加工): Tube ends are cut, deburred, and processed according to customer requirements — including threading, flanging, or beveling for welding connections.
- Surface Treatment (表面处理): Depending on application requirements, the coil tube may undergo passivation (酸洗钝化), electropolishing, or mirror polishing to achieve the required surface roughness and corrosion resistance.
- Pressure Testing (压力测试): Each coil tube undergoes hydrostatic pressure testing at 1.5× the maximum working pressure to verify structural integrity and leak-tightness.
- Final Inspection & Packaging (终检与包装): Dimensional inspection (OD, wall thickness, coil diameter, pitch), visual inspection, and material certification review are conducted before export-grade packaging.
Applications
The stainless steel coil tube is engineered for a diverse range of demanding thermal and fluid handling applications:
- Direct Evaporation Ice Thermal Storage Systems (直接蒸发冰蓄冷系统): The coil tube serves as the core heat exchange element in ice thermal storage tanks, enabling efficient ice formation and melting cycles for peak-load shifting in commercial and industrial HVAC systems. This application is particularly relevant for reducing peak electrical demand and optimizing energy costs.
- Chilled Water Heat Exchangers (冷冻水换热器): Used in air handling units (AHUs), fan coil units (FCUs), and chiller condensers/evaporators for high-efficiency thermal transfer.
- Refrigeration & Air Conditioning (制冷与空调): Employed as evaporator and condenser coils in commercial refrigeration systems, walk-in coolers, and industrial cold storage facilities.
- Food & Beverage Processing (食品加工): Compliant with FDA and 3-A sanitary standards, used in pasteurizers, condensers, and cooling systems in dairy, brewing, and beverage industries.
- Pharmaceutical & Biotechnology (制药与生物技术): Used in process heat exchangers, bioreactor cooling jackets, and cleanroom HVAC systems requiring hygienic-grade materials.
- Marine & Offshore Applications (海洋与海上应用): AISI 316/316L coil tubes resist seawater corrosion in shipboard HVAC systems and offshore platform cooling circuits.
- Power Generation & Energy Systems (电力与能源系统): Utilized in waste heat recovery, solar thermal collectors, and geothermal heat exchange systems.
- Chemical Processing (化工处理): Resistant to a wide range of chemicals, used in heat exchangers for acid, alkali, and solvent processing.
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd maintains a comprehensive quality management system and holds the following certifications and complies with the following standards:
- ISO 9001:2015 — Quality Management System certification ensuring consistent product quality and process control.
- ISO 14001:2015 — Environmental Management System certification demonstrating environmental responsibility.
- ISO 45001:2018 — Occupational Health and Safety Management System certification.
- CE Marking (欧盟CE认证) — Compliance with European health, safety, and environmental protection standards.
- EN 10204 3.1 Material Test Certificate (材质测试证书) — Third-party verified material certification for each production batch.
- GB/T 19001 — Chinese national standard for quality management systems.
- ASTM A213 / A269 — Compliance with American Society for Testing and Materials standards for seamless and welded stainless steel tubing.
- EN 10216-5 — European standard for seamless heat exchanger and boiler tubes of stainless steel.
- GB/T 12771 — Chinese national standard for welded stainless steel seamless and welded tubes for general application.
- JIS G3459 — Japanese Industrial Standard for stainless steel tubes for heat exchangers.
- ASME BPV Code — Compliance for pressure vessel and piping applications (where applicable).
- 3-A Sanitary Standards — For food-grade and pharmaceutical applications.
- NACE MR0175 / ISO 15156 — Compliance for sour service applications (AISI 316 grades).
Unique Selling Points
- Superior Thermal Performance: The precision helical coil geometry maximizes heat transfer surface area per unit volume, achieving up to 30% higher thermal efficiency compared to conventional straight-tube heat exchangers in ice thermal storage and refrigeration applications.
- Exceptional Corrosion Resistance: Available in AISI 304, 316, and 316L grades, providing outstanding resistance to chlorides, acids, and aggressive refrigerants — extending service life beyond 25 years in demanding environments.
- Customizable Geometry: Flexible customization of outer diameter, wall thickness, coil pitch, and coil diameter to meet specific system design requirements, enabling optimal integration into existing thermal storage and heat exchange systems.
- Direct Evaporation Ice Storage Expertise: Deep technical knowledge in direct evaporation ice thermal storage systems, informed by research into ice formation dynamics and thermal cycling behavior, ensuring coil tubes are optimized for reliable ice nucleation, growth, and melting cycles.
- Rigorous Quality Control: Every production batch undergoes multi-stage inspection including spectroscopic material analysis, dimensional verification, hydrostatic pressure testing, and surface roughness measurement, backed by ISO 9001-certified quality management.
- Wide Material Range: Availability of multiple stainless steel grades (304, 316, 316L, 321) allows customers to select the optimal material balance between cost, corrosion resistance, and mechanical performance for their specific application.
- Export-Grade Reliability: Products are manufactured to international standards (ASTM, EN, JIS, GB) and are suitable for global distribution, with full traceability from raw material to finished product.
- Cost-Effective Solution: The compact coil design reduces material consumption and installation footprint compared to equivalent straight-tube systems, delivering lower total cost of ownership over the system lifecycle.
Technical Reference: Direct Evaporation Ice Thermal Storage System
The coil tube product is particularly relevant to direct evaporation ice thermal storage systems, where refrigerant (typically ammonia R717 or CO₂ R744) evaporates directly inside the stainless steel coil tube, absorbing heat from the surrounding water/ice slurry. This configuration eliminates the need for intermediate heat transfer fluids, achieving higher system COP (Coefficient of Performance) and improved thermal efficiency. The stainless steel coil tube must withstand repeated thermal cycling between freezing and melting temperatures, mechanical stress from ice expansion, and potential corrosion from ammonia or CO₂ refrigerants. The material selection and manufacturing process described above are specifically engineered to address these demanding operational conditions.