Stainless Steel Coil Tube (Coiltube) — Model JX-CT Series
Product Overview
The Stainless Steel Coil Tube (Model JX-CT Series), manufactured by Wenzhou Jixing Metal Materials Co., Ltd., is a precision-engineered continuous-length tubular product wound into a compact coil configuration for efficient transport, storage, and downstream processing. This product is specifically designed for integration into Direct Flame Odor Removal Devices (盘管直焰式除臭装置) and other industrial heat exchange, gas treatment, and fluid conveyance systems. The coil tube architecture eliminates the need for intermediate welding joints, thereby ensuring superior structural integrity, enhanced flow uniformity, and extended service life under demanding operational conditions.
As a key component in environmental protection and industrial process engineering, the JX-CT Series Coil Tube delivers exceptional performance in catalytic oxidation, thermal treatment, and odor abatement applications where high-temperature resistance, chemical durability, and long-term reliability are paramount.
Material & Properties
The Coil Tube is fabricated from high-grade austenitic stainless steel alloys, selected to meet the rigorous demands of high-temperature and corrosive environments. The primary material grades include:
- 304 (UNS S30400) — General-purpose grade offering excellent corrosion resistance, formability, and weldability. Suitable for moderate temperature environments up to 870°C (1600°F).
- 321 (UNS S32100) — Titanium-stabilized grade providing superior resistance to intergranular corrosion. Recommended for sustained operating temperatures between 600°C and 900°C (1112°F–1652°F).
- 310S (UNS S31008) — High-chromium, high-nickel grade offering outstanding resistance to oxidation and scaling at temperatures up to 1150°C (2094°F). Ideal for direct flame exposure applications.
- 316L (UNS S31603) — Low-carbon molybdenum-bearing grade with enhanced resistance to pitting and crevice corrosion in chloride-containing environments.
Key Mechanical and Physical Properties (Typical — Grade 321)
| Property | Specification |
|---|---|
| Yield Strength (0.2% offset) | ≥ 205 MPa (30 ksi) |
| Tensile Strength | 515–730 MPa (75–106 ksi) |
| Elongation at Break | ≥ 40% |
| Thermal Conductivity (at 100°C) | 16.3 W/(m·K) |
| Thermal Expansion Coefficient (20–800°C) | 17.5 × 10⁻⁶ /°C |
| Maximum Service Temperature | 900°C (1652°F) |
| Density | 7.93 g/cm³ |
| Surface Finish | No. 1 Annealed / 2B / BA / Custom (Ra ≤ 0.5 μm available) |
Specifications
| Parameter | Specification Range | Notes |
|---|---|---|
| Outer Diameter (OD) | Φ6.0 mm – Φ114.3 mm (¼" – 4") | Custom diameters available upon request |
| Wall Thickness | 0.30 mm – 6.00 mm (0.012" – 0.236") | Tolerance: ±10% or per ASME B36.19M |
| Coil Inner Diameter (ID) | Φ300 mm – Φ1200 mm (12" – 48") | Adaptable to downstream forming equipment |
| Coil Length (per roll) | 50 m – 500 m (164 ft – 1,640 ft) | Continuous length available for automated processing |
| Material Grades | 304, 321, 310S, 316L, 347H, Custom Alloys | Mill certificates provided per lot |
| Manufacturing Standard | ASTM A213 / A269 / ASME B36.19M / EN 10216-5 | Compliant with international pipe standards |
| End Condition | Plain / Beveled / Flanged / Custom | Tail pieces trimmed and sealed |
| Surface Treatment | Pickle & Passivate (P&P) | Chromium oxide passive film, Cl⁻ ≤ 50 ppm |
| Packaging | Wooden pallet / Steel crate with moisture barrier | Export-ready, ISPM-15 compliant |
Manufacturing Process
The production of the JX-CT Series Stainless Steel Coil Tube follows a rigorous multi-stage process to ensure dimensional accuracy, metallurgical quality, and surface integrity:
- Raw Material Procurement & Inspection — Hot-rolled coil stock is sourced from certified mills (e.g., Outokumpu, Sandvik, POSCO, or equivalent domestic producers). Incoming material undergoes spectroscopic analysis (OES) to verify chemical composition, along with mechanical testing per ASTM E8/E8M.
- Slitting & Leveling — The wide coil is precisely slit to target width using a high-precision slitting line, followed by tension leveling to eliminate coil set and ensure flatness within 0.5 mm/m.
- Forming & Welding (ERW/FP) — The flat strip is fed through a series of forming rollers to achieve the target circular cross-section. Seaming is accomplished via Electrical Resistance Welding (ERW) or Flash Butt Welding (FP), with weld parameters controlled in real time.
- Heat Treatment (Solution Annealing) — The formed tube undergoes continuous solution annealing in a protective atmosphere (nitrogen or argon) at temperatures between 1050°C and 1150°C, followed by controlled cooling. This process restores full austenitic microstructure, relieves residual stresses, and ensures uniform mechanical properties.
- Pickling & Passivation (P&P) — The annealed tube is treated with a mixed acid solution (HNO₃/HF) to remove oxide scale, followed by passivation in dilute nitric acid to establish a protective chromium oxide film.
- Dimensional & Non-Destructive Testing (NDT) — Each coil is inspected for OD, wall thickness, straightness, and roundness. Weld integrity is verified through Eddy Current Testing (ECT) or Visual + Dye Penetrant Testing (PT) in accordance with ASTM E709 and ASTM E165.
- Coiling & Packaging — The finished tube is coiled to the specified inner diameter, labeled with heat traceability data, and packaged for transport.
Applications
The JX-CT Series Stainless Steel Coil Tube is engineered for a diverse range of industrial and environmental applications:
- Direct Flame Odor Removal Devices (盘管直焰式除臭装置) — The primary application domain. The coil tube serves as the heat exchange and catalytic reaction surface, where volatile organic compounds (VOCs) and malodorous gases are combusted at high temperatures (typically 600°C–900°C) to achieve complete oxidation and odor elimination. The continuous coil configuration maximizes heat transfer area within a compact footprint.
- Industrial Heat Exchangers — Air-to-air, liquid-to-liquid, and gas-to-gas heat exchange systems in chemical processing, food and beverage manufacturing, and HVAC applications.
- Boiler & Furnace Systems — Fire tubes, convection tubes, and superheater elements in industrial boilers, steam generators, and process furnaces.
- Environmental & Waste Treatment — Thermal oxidizers, regenerative thermal oxidizers (RTO), and regenerative catalytic oxidizers (RCO) for VOC abatement in petrochemical, pharmaceutical, and coating industries.
- Food Processing & Pharmaceutical — Steam sterilization systems, hygienic fluid transfer lines, and sanitary process piping where surface finish and corrosion resistance are critical.
- Automotive & Aerospace — Exhaust system components, turbocharger manifolds, and fuel delivery lines requiring high-temperature and high-pressure resistance.
- Oil & Gas — Downhole tubing, heat tracing lines, and wellhead instrumentation piping in sour service environments.
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system and holds the following certifications to assure product conformity:
- ISO 9001:2015 — Quality Management System certification ensuring consistent product quality and customer satisfaction.
- ISO 14001:2015 — Environmental Management System certification demonstrating commitment to sustainable manufacturing practices.
- ISO 45001:2018 — Occupational Health and Safety Management System certification.
- CE Marking — Conformity with European Union directives for pressure equipment and machinery (PED 2014/68/EU where applicable).
- EN 10204 3.1 Certificate — Third-party inspection and material testing reports issued per lot shipment.
- Mill Test Certificates (MTC) — Provided for every production lot, including chemical analysis, mechanical test results, and heat treatment records.
Unique Selling Points
- Seamless Joint-Free Continuity — The coil tube format eliminates butt welds present in straight-length pipe, reducing potential failure points and ensuring uniform flow characteristics throughout the entire length.
- Optimized for Direct Flame Applications — Specifically designed and validated for high-temperature odor removal systems, with material selections (321, 310S) proven for sustained thermal cycling and oxidation resistance.
- Full Traceability — Every coil is traceable to its mill heat number, with complete documentation from raw material through final inspection.
- Customizable Specifications — Flexible manufacturing capability allows customization of diameter, wall thickness, material grade, coil dimensions, and surface finish to meet project-specific requirements.
- Cost-Efficient Processing — The continuous coil format reduces downstream fabrication costs by minimizing cutting waste, welding labor, and handling operations.
Technical Advisory: For applications involving sustained exposure to temperatures exceeding 800°C or aggressive chloride-containing atmospheres, Wenzhou Jixing Metal Materials Co., Ltd. recommends consulting with their engineering team to select the optimal alloy grade (e.g., 310S, 347H, or custom precipitation-hardening alloys) and specify appropriate surface treatment protocols to ensure maximum service life and operational reliability.