Stainless Steel Coil Tube (Coiltube) — Bending-Formed Tubular Product

Product Overview

The Stainless Steel Coil Tube (Coiltube) is a precision-formed tubular product manufactured by bending and coiling stainless steel strip or plate material using specialized plate rolling machines (Coiling Machines). Produced by Wenzhou Jixing Metal Materials Co., Ltd, this product category encompasses a wide range of diameters, wall thicknesses, and coil configurations designed for industrial, commercial, and architectural applications. The coil tube is distinguished from seamless or welded tubes by its forming methodology — the material is continuously rolled and shaped into a helical or circular tube geometry, offering superior dimensional control and material efficiency.

The manufacturing technique of "skillful coil tube bending on a plate rolling machine" (《卷板机上巧弯盘管》) represents an advanced process optimization that enables tight tolerances, uniform wall thickness distribution, and high production throughput while minimizing material waste.

Material & Properties

Available Grades

Mechanical Properties (Typical — SUS304)

Property Specification Test Standard
Tensile Strength (抗拉强度) ≥ 520 MPa ASTM A270 / EN 10216
Yield Strength (屈服强度) ≥ 205 MPa ASTM A270 / EN 10216
Elongation (延伸率) ≥ 40% ASTM A270 / EN 10216
Hardness (硬度) ≤ 210 HB (annealed) ASTM A923
Density (密度) 8.0 g/cm³ —
Thermal Conductivity (导热系数) 16.3 W/(m·K) @ 100°C —
Corrosion Resistance (耐腐蚀性) Excellent in atmospheric, acidic, and alkaline environments ASTM G48 / ISO 3515

Specifications

Parameter Range / Value Notes
Outer Diameter (外径) Φ6 mm – Φ600 mm Custom sizes available
Wall Thickness (壁厚) 0.3 mm – 6.0 mm ±0.1 mm tolerance
Coil Length (盘管长度) 5 m – 500 m (continuous) Dependent on diameter and wall thickness
Coil Inner Diameter (盘圈内径) Φ300 mm – Φ2000 mm Customizable per customer requirements
Tolerance on Diameter (直径公差) ±0.5% (standard) / ±0.3% (precision) Per ASTM A270
Surface Finish (表面处理) 2B, BA, No.4, HL, Mirror (8K) As-rolled or post-processed
End Condition (端部状态) Plain end, Beveled, Threaded, Flanged Custom fabrication available
Welding Quality (焊缝质量) Fully welded / Seam-welded with internal TIG finish X-ray inspected (optional)
Maximum Operating Temperature (最高使用温度) Up to 870°C (304/321) / 1150°C (310S) Grade-dependent
Minimum Operating Temperature (最低使用温度) Down to −196°C (cryogenic) Full toughness retention

Manufacturing Process

The production of Stainless Steel Coil Tubes at Wenzhou Jixing Metal Materials Co., Ltd employs a refined bending-and-coiling methodology executed on precision plate rolling machines. The process is as follows:

  1. Material Selection & Inspection (原材料检验) — Incoming stainless steel coil or strip is verified for chemical composition (per ASTM E1467 spark emission spectrometry), mechanical properties, and surface quality.
  2. Slitting & Leveling (分条与平整) — The master coil is slit to the required width using precision slitting lines, followed by leveling to eliminate coil set and ensure flatness within ±0.1 mm/m.
  3. Forming & Bending (成型与弯曲) — The leveled strip is fed into the plate rolling machine (卷板机), where a series of precision rollers progressively bend the material into a tubular cross-section. The "skillful bending" technique involves optimized roller configurations, controlled feed rates, and calibrated inter-pass reduction ratios to achieve uniform wall thickness and precise diameter.
  4. Welding (焊接) — The formed tube is seam-welded using TIG (Tungsten Inert Gas) welding with automatic wire feeding to produce a high-integrity longitudinal weld seam. Weld parameters are precisely controlled to minimize heat-affected zone (HAZ) distortion.
  5. Heat Treatment (热处理) — Solution annealing is performed at 1010–1150°C followed by rapid quenching to restore full austenitic microstructure, eliminate residual stresses, and ensure maximum corrosion resistance.
  6. Surface Finishing (表面处理) — The annealed tube undergoes pickling (酸洗) and passivation (钝化) to remove scale and form a protective chromium oxide layer. Additional polishing or brushing is applied per the specified finish grade.
  7. Coiling (盘绕) — The finished tube is coiled onto precision-wound mandrels using a controlled tension system to maintain dimensional accuracy and prevent surface marking.
  8. Final Inspection & Packaging (终检与包装) — Each coil undergoes dimensional verification, hydrostatic testing (per ASTM A270), and visual inspection. Coils are protected with moisture-absorbing packaging and wooden crates for export.

Applications

Quality Certifications

Unique Selling Points

1. Advanced Bending Technology (先进弯曲技术) — The proprietary "skillful bending on plate rolling machine" process achieves wall thickness uniformity within ±0.05 mm and diameter tolerance of ±0.3%, surpassing industry averages.

2. Continuous Production Capability (连续生产能力) — Up to 500 meters of continuous coil tube can be produced in a single run, minimizing weld joints and maximizing structural integrity.

3. Material Efficiency (材料利用率) — The forming process achieves material utilization rates exceeding 95%, significantly reducing waste compared to traditional cutting methods.

4. Customization Flexibility (定制化灵活性) — Full customization of diameter, wall thickness, surface finish, coil configuration, and end treatment to meet specific project requirements.

5. Comprehensive Testing (全面检测) — Every production batch undergoes spectroscopic analysis, hydrostatic testing, dimensional verification, and surface inspection with full traceability.

Technical Standards Referenced