Stainless Steel Coil Tube — Model No. 878
1. Product Overview
The Stainless Steel Coil Tube (Model No. 878) is a precision-engineered coiled tubular product manufactured by Wenzhou Jixing Metal Materials Co., Ltd. This product is designed for applications requiring high-temperature resistance, corrosion resistance, and thermal stability. The coil tube is formed through a continuous cold-drawing and coiling process, resulting in a seamless, uniform tubular structure that maintains dimensional accuracy throughout its entire length.
The product is particularly suited for heat exchanger systems, boiler installations, automotive radiators, and industrial thermal management applications where reliable performance under sustained thermal cycling is critical. The coil geometry enables compact installation footprints while maximizing surface-area-to-volume ratios, making it an optimal choice for heat transfer-intensive environments.
2. Material & Properties
2.1 Material Grades
The coil tube is fabricated from austenitic stainless steel grades, primarily conforming to the following international standards:
- AISI 304 / EN 1.4301 (X2CrNi19-10) — General-purpose corrosion resistance
- AISI 316 / EN 1.4401 (X2CrNiMo17-12-2) — Enhanced chloride and pitting resistance
- AISI 321 / EN 1.4541 (X8CrNiNb18-10) — Stabilized grade for high-temperature service
- AISI 310S / EN 1.4845 (X15CrNiSi25-21) — Ultra-high-temperature applications
2.2 Key Mechanical and Physical Properties
| Property | Specification | Test Standard |
|---|---|---|
| Tensile Strength (UTS) | ≥ 520 MPa (304); ≥ 515 MPa (316) | ASTM A213 / EN 10216-5 |
| Yield Strength (0.2% offset) | ≥ 205 MPa | ASTM E8 |
| Elongation at Break | ≥ 40% | ASTM E8 | Hardness (HV) | ≤ 200 HV | ASTM E92 |
| Maximum Service Temperature | 870°C (304); 870°C (316); 1150°C (321); 1150°C (310S) | ASME BPVC Section I |
| Corrosion Resistance | Excellent in oxidizing acids; superior to carbon steel in chloride environments (316) | ASTM G48 / ISO 9326 |
| Thermal Conductivity (25°C) | 16.3 W/m·K (304); 16.3 W/m·K (316) | ASTM E153 |
3. Specifications
| Parameter | Specification |
|---|---|
| Product Code | 878 |
| Product Category | Coil Tube (盘管) |
| Outer Diameter (OD) | 6.0 mm – 32.0 mm (customizable) |
| Wall Thickness | 0.5 mm – 3.0 mm |
| Coil Length (Continuous) | 10 m – 500 m (per coil) |
| Coil Winding Diameter | 300 mm – 1200 mm |
| Surface Finish | Bright Annealed (BA), Pickled & Passivated, or Custom |
| Surface Roughness (Ra) | ≤ 0.8 μm (BA finish); ≤ 1.6 μm (standard) |
| Dimensional Tolerance | OD: ±0.1 mm; Wall Thickness: ±10% |
| Welding Condition | Non-welded (seamless) or Welded (ER308L/ER316L filler) |
| Applicable Standards | ASTM A213, ASME SA-213, EN 10216-5, GB/T 14976 |
| Heat Treatment | Solution Annealing at 1050–1150°C followed by rapid cooling |
| Coil Packaging | Wooden pallet with moisture-proof wrapping; export-grade seaworthy packing |
4. Manufacturing Process
The production of the Stainless Steel Coil Tube follows a rigorous multi-stage manufacturing workflow designed to ensure dimensional precision, metallurgical integrity, and surface quality:
- Raw Material Selection: Ingot-grade stainless steel from certified suppliers, verified through spectroscopic analysis (OES) to confirm chemical composition within ASTM/EN specifications.
- Hurricane Forging & Hot Rolling: The steel is hot-rolled to produce seamless pipe blanks with controlled wall thickness and outer diameter.
- Pickling & Descaling: Hot acid pickling removes oxide scale formed during hot rolling, restoring the base metal surface.
- Cold Drawing: The pipe blanks undergo cold drawing through precision dies to achieve final dimensional tolerances and enhanced mechanical properties.
- Bright Annealing (BA): The drawn tubing is annealed in a controlled hydrogen or nitrogen atmosphere to relieve cold-work stresses, restore ductility, and achieve a bright, oxide-free surface finish.
- Coil Winding & Temperature Control: The annealed tubing is coiled using a programmable coil-winding system. The winding process incorporates a temperature control system based on MCGSE (MCGS Embedded), a modular configurable graphic surveillance and control system. This PLC-based control system ensures precise regulation of winding tension and temperature parameters, preventing deformation, stress concentration, and surface damage during the coiling operation. The MCGSE system monitors and adjusts heating elements, cooling fans, and motor speed in real-time to maintain optimal coil geometry.
- Quality Inspection: Every coil undergoes 100% visual inspection, dimensional measurement (OD, wall thickness via ultrasonic gauging), and random sampling for mechanical testing (tensile, hardness, elongation) and chemical analysis.
- Passivation & Packaging: Final passivation treatment enhances corrosion resistance, followed by protective wrapping and export-grade packaging.
5. Applications
The Stainless Steel Coil Tube (Model No. 878) serves a broad spectrum of industrial applications:
- Heat Exchangers & Boilers: Primary and secondary heat exchanger coils in power generation, petrochemical, and process industries where thermal efficiency and corrosion resistance are paramount.
- Automotive Radiators & Turbochargers: Oil cooler coils, intercooler tubes, and radiator assemblies requiring sustained performance under high thermal loads.
- Food & Pharmaceutical Processing: Sanitary-grade heat transfer coils compliant with FDA and EHEDG standards for hygienic processing environments.
- Marine & Offshore Equipment: Seawater cooling coils in ship propulsion systems and offshore platform utilities, leveraging 316-grade chloride resistance.
- HVAC & Refrigeration Systems: Evaporator and condenser coils in commercial and industrial air-conditioning installations.
- Solar Thermal Collectors: Absorber tubes in evacuated tube solar thermal systems requiring high-temperature stability and UV resistance.
- Industrial Process Heating: Integration with MCGSE-based temperature control systems for precise thermal management in continuous manufacturing processes.
6. Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality assurance framework ensuring international compliance:
- ISO 9001:2015 — Quality Management System Certification
- ISO 14001:2015 — Environmental Management System Certification
- EN 10204 3.1 — Material Test Certificate (Mill Test Report) provided with every shipment
- ASME "S" Stamp / "U" Stamp — National Board Registration for pressure vessel components (where applicable)
- CE Marking — Conformity with European Pressure Equipment Directive (PED 2014/68/EU)
- GB/T 14976 — Compliance with Chinese national standard for cold-rolled seamless stainless steel tubes
- Third-Party Inspection: Available upon request (SGS, BV, TUV, Lloyd's)
7. Unique Selling Points
- Integrated MCGSE Temperature Control: The coil winding process is governed by a state-of-the-art MCGSE (Modular Configurable Graphic Surveillance and Control) embedded system, ensuring real-time monitoring and precise regulation of thermal and mechanical parameters during coiling — a significant differentiator in coil quality consistency.
- Full Traceability: Each coil is traceable from raw material ingot to final product through a digital batch management system, providing complete material pedigree documentation.
- Multi-Grade Availability: A single product platform offering grades 304, 316, 321, and 310S to cover service temperatures from ambient to 1150°C without design redesign.
- Precision Cold-Drawn Dimensions: Tolerances as tight as ±0.1 mm on OD and ±10% on wall thickness, ensuring plug-fit compatibility in heat exchanger tube sheets.
- Bright Annealed Surface: Superior surface finish (Ra ≤ 0.8 μm) reduces fouling in heat transfer applications, extending maintenance intervals and improving thermal efficiency.
- Customizable Coil Geometry: Tailored winding diameters, coil lengths, and surface treatments to match specific customer integration requirements.
Note: All specifications listed are subject to the applicable standards at the time of manufacture. Custom specifications and non-standard dimensions are available upon request. Material test certificates (EN 10204 Type 3.1) are provided with each shipment. For detailed technical data sheets and compliance documentation, contact Wenzhou Jixing Metal Materials Co., Ltd. directly.