Stainless Steel Coil Tube (盘管) — Product No. 1254
Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. presents its precision-engineered Stainless Steel Coil Tube (盘管), a high-performance tubular product supplied in continuous coil form for downstream processing applications. Designed to meet the rigorous demands of chemical processing, food-grade equipment, pharmaceutical manufacturing, and industrial pipe conveyor systems, this product combines superior corrosion resistance, mechanical integrity, and dimensional consistency in a single solution.
The coil tube is manufactured from austenitic and duplex stainless steel grades, cold-worked to achieve precise wall thickness tolerances and uniform mechanical properties throughout the entire coil length. The product is particularly suited for applications requiring continuous-length tubing with minimal joint requirements, including vertical series disk pipe conveyor (立式串联圆盘管道输送机) systems where optimal tray spacing and structural reliability are critical.
Material & Properties
Available Grades
- A2 (304 / SUS304) — General-purpose austenitic stainless steel with excellent corrosion resistance and formability.
- A3 (316 / SUS316) — Molybdenum-enhanced austenitic grade offering superior resistance to pitting and crevice corrosion in chloride environments.
- A4 (321 / SUS321) — Titanium-stabilized austenitic grade for elevated-temperature service (up to 870 °C) with resistance to intergranular corrosion.
- 316L / 304L — Low-carbon variants for welding applications requiring reduced sensitization risk.
- 2205 Duplex — High-strength duplex stainless steel (yield strength ≥ 450 MPa) for aggressive chemical and marine environments.
Mechanical Properties (Cold-Worked Condition)
| Property | 304 Grade | 316 Grade | 2205 Duplex |
|---|---|---|---|
| Tensile Strength (MPa) | ≥ 515 | ≥ 515 | ≥ 550 |
| Yield Strength (MPa) | ≥ 205 | ≥ 205 | ≥ 450 |
| Elongation (%) | ≥ 40 | ≥ 35 | ≥ 25 |
| Hardness (HRB) | 70–95 | 70–95 | 95–110 |
| Density (g/cm³) | 8.00 | 8.03 | 7.80 |
| Service Temperature Range (°C) | -196 to +870 | -196 to +870 | -50 to +300 |
Surface Finish Options
- No. 1 Finish — Hot-rolled, pickled, and descaled; suitable for industrial structural applications.
- 2B Finish — Cold-rolled, annealed, and pickled; smooth, matte appearance for general use.
- BA (Bright Annealed) Finish — Mirror-quality surface achieved in controlled-atmosphere furnaces; ideal for pharmaceutical and food-contact applications.
- Electropolished Finish — Ra ≤ 0.4 μm; maximized corrosion resistance and hygienic surface for bioprocessing.
Specifications
| Parameter | Specification |
|---|---|
| Outer Diameter (OD) | Φ 3.0 mm – Φ 50.8 mm (custom sizes available up to Φ 100 mm) |
| Wall Thickness | 0.3 mm – 3.0 mm (tolerance: ±0.05 mm or ±10%) |
| Coil Length | 50 m – 500 m per coil (continuous length) |
| Coil Inner Diameter | Φ 100 mm / Φ 150 mm / Φ 200 mm (standard); custom upon request |
| Coil Weight | Up to 2,000 kg per coil |
| Dimensional Tolerance (OD) | ±0.05 mm (precision grade); ±0.1 mm (standard grade) |
| Dimensional Tolerance (WT) | ±0.03 mm (precision grade); ±0.08 mm (standard grade) |
| Roundness | ≤ 0.5% of OD |
| Straightness (after straightening) | ≤ 1 mm/m |
| End Condition | Flat-cut, chamfered, or beveled per customer specification |
| Packing | Export-grade wooden crates or steel drums with moisture-absorbing desiccants |
Manufacturing Process
The production of Wenzhou Jixing's stainless steel coil tubes follows a multi-stage precision manufacturing process:
- Strip Preparation — Cold-rolled stainless steel strip is sourced from certified mills and inspected for chemical composition, mechanical properties, and surface quality in accordance with ASTM A480 / EN 10088 standards.
- Forming (Rolling) — The strip is fed through a multi-stand rolling mill with progressive die sets to achieve the target outer diameter and wall thickness. Hydraulic tension control ensures uniform springback compensation.
- Welding (if welded tube) — A high-frequency induction welding (HFW) process with internal gas shielding (argon or nitrogen) produces a hermetic longitudinal seam. The weld zone is precisely ground and polished to match the parent material surface.
- Heat Treatment — Solution annealing at 1040–1120 °C followed by controlled cooling (air or water quench) restores full austenitic microstructure, eliminates cold-work stresses, and maximizes corrosion resistance.
- Pickling & Passivation — Acid pickling removes oxide scale; subsequent passivation with nitric or citric acid forms a stable chromium oxide layer (Cr₂O₃) for enhanced corrosion protection.
- Coiling — The finished tube is wound onto precision-machined coils with uniform tension to prevent deformation, ovality, or surface scratches during storage and transport.
- Final Inspection — 100% ultrasonic thickness testing (UT), visual surface inspection, dimensional verification using laser diameter gauges, and optional eddy-current testing for seam integrity.
Applications
Industrial Pipe Conveyor Systems
The coil tube serves as a primary structural and conveying component in vertical series disk pipe conveyors (立式串联圆盘管道输送机). In such systems, the coil tube forms the enclosed conduit through which product-carrying disks travel. The determination of optimal tray (disk) spacing — a critical design parameter — depends on the tube's internal diameter, surface smoothness, and mechanical stiffness. The high dimensional accuracy and consistent inner bore of Wenzhou Jixing's coil tubes enable precise calculation and implementation of tray spacing, ensuring efficient material flow with minimal blockage or spillage.
Additional Applications
- Food & Beverage Processing — Hygienic tubing for dairy, brewing, and juice production lines (BA or electropolished finish).
- Pharmaceutical Equipment — Clean-in-place (CIP) compatible tubing for bioreactors, chromatography, and sterile fluid transfer.
- Chemical Processing — Heat exchangers, reactors, and piping systems handling aggressive acids and alkalis (316L / 2205 grades).
- Oil & Gas — Downhole instrumentation tubing and wellhead flow control components.
- Automotive & Aerospace — Precision fuel lines, hydraulic circuits, and exhaust system components.
- Medical Devices — Endoscope tubing, catheter housings, and surgical instrument shafts.
- Heat Exchangers & Boilers — Tube bundles requiring high thermal conductivity and long-term corrosion resistance.
Quality Certifications & Standards
| Category | Standard / Certification |
|---|---|
| Material Compliance | ASTM A554 / A555, EN 10217-7, GB/T 12771, JIS G3459 |
| Dimensional Standards | ASTM A480, ISO 13679, GB/T 14976 |
| Quality Management | ISO 9001:2015 Certified |
| Environmental Management | ISO 14001:2015 Certified |
| Food Safety | ISO 22000 / FDA 21 CFR Compliance (BA finish grades) |
| Pressure Vessel | ASME BPE (Bioprocessing Equipment) — available upon request |
| Material Testing | Chemical analysis (OES + wet chemistry), tensile testing, impact testing, hardness testing, PMI (positive material identification via XRF) |
| Third-Party Inspection | SGS / BV / TÜV inspection available; MTC (Mill Test Certificate) EN 10204 3.1 provided with each shipment |
Unique Selling Points
- Continuous Length Advantage — Coil format eliminates the need for field welding of short lengths, reducing labor costs, joint failure points, and contamination risks in critical applications.
- Precision Dimensional Control — Laser-based inline monitoring ensures OD and wall thickness tolerances as tight as ±0.03 mm, enabling reliable design calculations for pipe conveyor tray spacing optimization.
- Multi-Grade Flexibility — A single supplier offering 304, 316, 321, 316L, 304L, and 2205 duplex grades simplifies procurement and ensures consistent quality across product lines.
- Custom Surface Finishes — From industrial No. 1 to pharmaceutical-grade electropolished (Ra ≤ 0.4 μm), the product line accommodates the full spectrum of surface quality requirements.
- Wenzhou Manufacturing Heritage — Leveraging the world's premier stainless steel processing hub, Wenzhou Jixing combines advanced equipment with decades of metallurgical expertise to deliver cost-effective, high-quality coil tubes.
- Traceability & Documentation — Every coil is accompanied by a full MTC (EN 10204 3.1), chemical composition report, and mechanical test results, ensuring complete material traceability from mill to end-user.
Technical Advisory Note
For applications involving vertical series disk pipe conveyors, it is recommended to select coil tubes with a minimum surface roughness of Ra ≤ 0.8 μm and an inner diameter tolerance of ±0.05 mm. These parameters directly influence the friction coefficient between the conveyor disks and the tube wall, which governs the optimal tray spacing calculation. Wenzhou Jixing Metal Materials Co., Ltd. provides engineering consultation services to assist customers in determining the appropriate tube specification for their specific conveyor design parameters, including product throughput, material characteristics, and installation geometry.