Stainless Steel Coil Tube (Coiltube) — Product Technical Specification

Product Overview

The Stainless Steel Coil Tube (Coiltube) manufactured by Wenzhou Jixing Metal Materials Co., Ltd. (Product No. 324) is a precision-engineered cold-rolled seamless tubing supplied in continuous coil form. Designed for high-volume fabrication requirements, this product eliminates the need for field cutting and butt-welding, significantly reducing material waste and assembly time. The coil configuration enables seamless integration with automated forming, bending, and welding systems, making it an ideal feedstock for HVAC (Heating, Ventilation, and Air Conditioning) systems, fluid transport applications, and structural components requiring corrosion-resistant performance.

Wenzhou Jixing Metal Materials Co., Ltd. leverages advanced metallurgical processing and quality control systems to deliver coil tubes that meet or exceed international standards for dimensional accuracy, mechanical properties, and surface finish.

Material & Properties

The coil tube is fabricated from austenitic stainless steel grades, primarily selected for their superior corrosion resistance, formability, and weldability. The following materials are available:

Key mechanical properties include tensile strength of 515–720 MPa, yield strength of 205–310 MPa, and elongation of ≥40% (annealed condition). The surface finish is available in 2B (Cold Rolled and Bright Annealed), No. 4 (Brushed), or BA (Bright Annealed) conditions depending on application requirements.

Technical Specifications

Parameter Specification / Range
Product Name Stainless Steel Coil Tube (Coiltube)
Product Number 324
Material Grades 304, 304L, 316, 316L, 321, 310S, 2205 (Duplex)
Outer Diameter (OD) 6.0 mm – 114.3 mm (¼" – 4½")
Wall Thickness 0.3 mm – 6.0 mm
Coil Width / Inner Diameter 300 mm – 600 mm (adjustable per order)
Coil Length per Spool 15 m – 50 m (continuous)
Tolerance (OD) ±0.05 mm – ±0.2 mm (per ASTM A778)
Tolerance (Wall) ±10% of nominal thickness
Surface Finish 2B, BA (Bright Annealed), No. 4 Brushed, Mirror (6K/8K)
Heat Treatment Annealed (Solution Annealed) at 1040–1120°C, Water Quenched
Applicable Standards ASTM A778, ASTM A213, EN 10216-5, GB/T 12771
Maximum Operating Temperature Up to 870°C (Grade 321); Up to 600°C (Grade 304/316)
Maximum Operating Pressure Up to 25 MPa (depending on OD and wall thickness)

Manufacturing Process

The production of the Stainless Steel Coil Tube follows a rigorous multi-stage manufacturing process to ensure dimensional precision and metallurgical integrity:

  1. Raw Material Selection: Virgin stainless steel strip is sourced from certified mills (e.g., Outokumpu, Nippon Steel, or domestic equivalents) and subjected to incoming quality inspection for chemical composition (via Spark OES analysis) and mechanical properties.
  2. Slitting & Leveling: Wide stainless steel coils are precision-slitted to the required tube blank width using CNC-controlled slitting lines with edge-quality inspection systems to ensure flatness within ±0.1 mm/m.
  3. Tube Forming (ERW/ODW): The flat strip is fed through a series of progressive roll-forming stations that gradually bend the strip into a helical tube shape. Longitudinal seam welding is achieved via Electromagnetic Resistance Welding (ERW) or Orbital Direct Welding (ODW), producing a high-integrity, penetration-free weld seam.
  4. In-Line Heat Treatment: Immediately following welding, the tube passes through a controlled atmosphere annealing furnace (nitrogen or hydrogen atmosphere) to relieve residual welding stresses and restore full austenitic microstructure.
  5. Pipe Milling & Sizing: The welded tube is passed through a series of sizing rolls to achieve precise outer diameter and wall thickness within specified tolerances.
  6. Surface Treatment: Depending on the required finish, the tube may undergo passivation (acid pickling to remove mill scale), electropolishing, or mechanical brushing.
  7. Quality Inspection: Every coil undergoes 100% ultrasonic testing (UT) for internal defects, hydrostatic pressure testing (per ASTM A778, Section 8), and dimensional verification via laser measurement systems.
  8. Coiling & Packaging: Finished tubes are coiled onto protective steel or wooden cores, wrapped with moisture-proof plastic film, and palletized for shipment.

Applications

The Stainless Steel Coil Tube from Wenzhou Jixing Metal Materials Co., Ltd. serves a broad range of industrial and commercial applications:

Quality Certifications & Compliance

Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management framework ensuring product reliability and regulatory compliance:

Each production batch is accompanied by a full Material Traceability Certificate (MTC) documenting chemical composition, mechanical test results, and heat treatment parameters, enabling customers to maintain complete quality documentation throughout their supply chain.

Unique Selling Points

Note: All specifications listed above are subject to engineering review for specific project requirements. Custom orders exceeding standard parameters may require additional lead time. Wenzhou Jixing Metal Materials Co., Ltd. reserves the right to modify specifications with prior customer notification.