Stainless Steel Coil Tube — Cleanroom-Grade Liquid Particle Count Certified
Wenzhou Jixing Metal Materials Co., Ltd. is a leading manufacturer of precision stainless steel coil tubes engineered for the most demanding industrial applications. Our coil tube product line is distinguished by rigorous cleanliness assurance, with every batch subjected to liquid particle counting (LPC) testing in accordance with international cleanroom standards. This ensures that the internal surfaces of our tubes meet the ultra-low particulate contamination thresholds required by pharmaceutical, semiconductor, food-grade, and high-purity chemical processing industries.
Product Overview
Stainless steel coil tubes are continuous, wound-length tubing products manufactured through seamless cold-drawn processes. Unlike discrete straight-length tubes, coil tubes are supplied in continuous coils, enabling seamless spooling, automated feeding, and minimal waste during downstream fabrication. Our coil tubes are produced with exceptional internal surface finish quality and are validated through multi-stage liquid particle counting (LPC) analysis at ≥0.1μm, ≥0.2μm, and ≥0.5μm thresholds — the gold standard for cleanroom-grade tube batch release.
Each coil tube batch undergoes a comprehensive cleanliness verification protocol that includes internal flushing, particle collection, and optical microscopy or laser diffraction-based particle counting. Only batches meeting or exceeding the specified particulate limits at all three size classifications are released for shipment. This methodology aligns with ISO 14644, ISO 3696, and USP <663> cleanroom and water quality frameworks.
Material & Properties
- Material Grades: 304, 304L, 316, 316L, 321, 310S, 904L, and custom alloy compositions available upon request
- Internal Surface Finish: Electropolished to Ra ≤ 0.5 μm (typical), with Ra ≤ 0.25 μm available for ultra-clean applications
- Corrosion Resistance: Superior resistance to pitting, crevice corrosion, and intergranular corrosion in aggressive chemical environments
- Mechanical Properties: High tensile strength with excellent ductility, ensuring reliable performance under cyclic pressure and thermal loading
- Non-Magnetic Option: 304L and 316L grades exhibit near-non-magnetic properties after proper heat treatment
Specifications
| Parameter | Specification |
|---|---|
| Outer Diameter (OD) | Φ1.0 mm – Φ50.8 mm (custom sizes available) |
| Wall Thickness | 0.1 mm – 3.0 mm |
| Coil Length | Standard: 50 m / 100 m; Custom lengths upon request |
| Internal Surface Roughness | Ra ≤ 0.5 μm (standard); Ra ≤ 0.25 μm (ultra-clean grade) |
| Particle Count — ≥0.1 μm | ≤ 1,000 particles/mL (cleanroom-grade release criterion) |
| Particle Count — ≥0.2 μm | ≤ 500 particles/mL (cleanroom-grade release criterion) |
| Particle Count — ≥0.5 μm | ≤ 100 particles/mL (cleanroom-grade release criterion) |
| Testing Method | Liquid Particle Counter (LPC) — Optical Scattering / Laser Diffraction |
| Applicable Standards | ISO 14644, ISO 3696, USP <663>, GB/T 14976, ASTM A269 |
| End Treatment | Clean-cut, deburred, protective caps or tape sealed |
| Packaging | Vacuum-sealed in moisture-barrier film; anti-static inner packaging |
Manufacturing Process
The production of cleanroom-grade stainless steel coil tubes at Wenzhou Jixing Metal Materials Co., Ltd. follows a tightly controlled multi-stage process designed to minimize contamination at every step:
- Seamless Forming: High-quality stainless steel billets are hot-rolled into seamless tube blanks, ensuring uniform microstructure and the absence of weld seams that could harbor particulate contamination.
- Cold Drawing & Coiling: Blanks are cold-drawn through precision-die tooling to achieve exact dimensional tolerances (±0.05 mm) and wound into continuous coils on controlled-diameter mandrels.
- Internal Surface Finishing: Tubes undergo mechanical polishing followed by electrochemical polishing (electropolishing) in controlled acid baths to achieve mirror-smooth internal surfaces with Ra ≤ 0.5 μm. This process removes surface oxides, embedded impurities, and micro-roughness that could trap particles.
- Passivation Treatment: A final nitric acid or citric acid passivation cycle ensures a stable, chromium-rich oxide layer that resists corrosion and prevents metal ion leaching.
- Cleanroom Washing: Tubes are flushed with ultra-pure water (UPW, 18.2 MΩ·cm) in a controlled cleanroom environment (ISO Class 7 minimum) to remove residual polishing agents and particulates.
- Liquid Particle Count Verification: A representative sample of each batch is flushed and collected for LPC analysis at ≥0.1 μm, ≥0.2 μm, and ≥0.5 μm thresholds. Only batches meeting all three criteria are approved for release.
- Packaging & Traceability: Approved coils are sealed in anti-static, moisture-barrier packaging with full batch traceability documentation including LPC test reports, material certifications, and dimensional inspection records.
Applications
- Pharmaceutical Manufacturing: CIP/SIP piping systems, reactor internals, bioreactor tubing, and clean water distribution lines where particle-free fluid transfer is critical
- Semiconductor & Electronics: Ultra-pure water (UPW) delivery systems, chemical vapor deposition (CVD) gas lines, and high-purity chemical feed systems
- Food & Beverage Processing: Hygienic fluid transfer lines, CIP systems, and beverage carbonation equipment requiring FDA-compliant tubing
- Medical Devices: Implant manufacturing fluid lines, medical gas delivery systems, and diagnostic equipment tubing
- Chemical Processing: Corrosive chemical transfer lines, reactor heat exchanger coils, and high-purity chemical dosing systems
- Cryogenic & Low-Temperature Systems: LNG transport tubing, superconducting magnet cooling lines, and cryogenic fluid handling
Quality Certifications & Assurance
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system ensuring every coil tube batch meets the highest standards of dimensional accuracy, material integrity, and cleanliness:
- ISO 9001:2015 — Quality Management System certification
- ISO 14001 — Environmental Management System certification
- ISO 14644 Compliance — Cleanroom particle control standards
- ISO 3696 — Water quality for laboratory and technical processes
- USP <663> — Water systems for pharmaceutical applications
- EN 10204 3.1 — Third-party material inspection certification available
- Material Traceability: Full mill certificates and heat-number traceability for every batch
- LPC Test Reports: Each batch ships with a detailed liquid particle count report documenting results at ≥0.1 μm, ≥0.2 μm, and ≥0.5 μm classifications
Key Differentiators
Triple-Threshold Particle Count Validation: Our ≥0.1 μm / ≥0.2 μm / ≥0.5 μm multi-level LPC testing provides comprehensive contamination profiling that exceeds single-threshold industry norms, giving customers full confidence in batch cleanliness.
- End-to-End Cleanroom Process Control: From electropolishing through final packaging, all critical operations are conducted in controlled cleanroom environments to prevent post-processing contamination.
- Full Traceability & Documentation: Every coil tube batch includes a complete quality dossier — material certificates, dimensional reports, LPC test data, and passivation verification — enabling seamless regulatory submission and customer audit compliance.
- Customization Capability: Flexible OD, wall thickness, coil length, and surface finish options allow precise matching to customer-specific application requirements.
- Cost-Efficient Continuous Supply: Coil format eliminates cut-loss waste and enables automated downstream processing, reducing overall system cost compared to discrete-length tubing.