Ultra-Low Moisture Stainless Steel Coil Tube for Electronic Specialty Gas Piping
Product Overview
Wenzhou Jixing Metal Materials Co., Ltd. presents its premium-grade stainless steel coil tube (Coil Tube), engineered specifically for electronic specialty gas distribution systems where ppm-level moisture control is critical. This coil tube is manufactured and processed to achieve exceptionally low residual moisture content, effectively eliminating the risk of hydrolysis reactions that can compromise semiconductor manufacturing processes, photolithography systems, and other high-purity gas delivery applications.
The product represents a specialized solution within the cleanliness inspection category, where Karl Fischer titration and dew point metering methodologies are employed to verify and guarantee moisture levels at parts-per-million (ppm) precision. This level of control distinguishes the coil tube from standard industrial-grade tubing and positions it as a reliable choice for the most demanding semiconductor and electronics manufacturing environments.
Material & Properties
Material Grade
- Base Alloy: SUS316L / ASTM 316L austenitic stainless steel, selected for superior corrosion resistance and compatibility with specialty electronic gases including chlorine, hydrogen chloride, anhydrous ammonia, and other reactive chemical species.
- Alternative Grades Available: SUS304L, SUS310S, and custom alloy configurations upon request.
- Microstructure: Fully solution-annealed austenitic structure ensuring maximum ductility and uniform corrosion resistance throughout the tube wall.
Key Physical & Chemical Properties
- Moisture Content: Controlled and verified at ppm level (<1 ppm H₂O) using Karl Fischer titration method and electronic dew point metering.
- Surface Finish: Electro-polished or passivated inner surface with Ra < 0.1 μm to minimize particulate generation and gas adsorption.
- Density: 8.00 g/cm³
- Operating Temperature Range: −196°C to +600°C (−321°F to +1,112°F)
- Chromium Content: ≥12.0% (provides inherent passivation and oxide film stability)
- Molybdenum Content: 2.0–3.0% (enhanced resistance to pitting and crevice corrosion)
- Carbon Content: ≤0.03% (prevents sensitization and intergranular corrosion)
Unique Selling Points
PPM-Level Moisture Control: Every coil tube batch is verified through dual-method moisture testing (Karl Fischer titration and capacitive dew point measurement), ensuring residual moisture remains below the critical threshold that triggers hydrolysis in specialty electronic gases. This eliminates contamination vectors that standard industrial tubing cannot address.
- Hydrolysis Prevention: The ultra-dry internal environment prevents moisture-induced hydrolysis reactions with reactive gases such as SiH₄, HBr, HF, and NF₃, which would otherwise generate corrosive byproducts and particulate contamination.
- Coil Configuration Advantage: Continuous coil form factor enables long, seamless runs without field joints, reducing potential leak points and contamination ingress in critical gas distribution networks.
- Traceable Cleanliness Documentation: Each shipment includes full traceability records with moisture test certificates, material mill test reports, and cleanliness inspection reports.
Specifications
| Parameter | Specification | Testing Method / Standard |
|---|---|---|
| Moisture Content | ≤1 ppm (H₂O) | Karl Fischer Titration (ASTM D665 / GB/T 7607) |
| Dew Point | ≤−60°C (−76°F) | Capacitive Dew Point Meter |
| Outer Diameter (OD) | 3.18 mm – 101.6 mm (1/8" – 4") | Direct Measurement (ISO 6507) |
| Wall Thickness | 0.10 mm – 3.00 mm (0.004" – 0.118") | Ultrasonic / Micrometer |
| Coil Length (per coil) | Up to 5,000 m (16,404 ft) | Production Log |
| Surface Roughness (Inner) | Ra ≤ 0.1 μm | Surface Profilometer (ISO 4287) |
| Surface Roughness (Outer) | Ra ≤ 0.4 μm | Surface Profilometer (ISO 4287) |
| Roundness | ≤0.5% of OD | Roundness Gauge |
| Coil Flatness | ≤2 mm per 1,000 mm | Flatness Gauge |
| Passivation Treatment | Citric Acid / Nitric Acid Passivation | ASTM A967 / ASTM A380 |
| Applicable Standards | ASTM A269, ASTM A213, ASME B36.19M, EN 10216-5 | — |
| Packaging | Plastic-wrapped coils in wooden crates; nitrogen-purged sealed | Internal SOP |
Manufacturing Process
Step 1 — Raw Material Selection & Incoming Inspection
Only certified austenitic stainless steel strip from approved mills is accepted. Incoming material undergoes spectroscopic verification (PMI/OES) to confirm chemical composition within specified tolerances. Initial moisture and cleanliness levels of the raw strip are assessed prior to processing.
Step 2 — Cold Rolling & Coiling
The stainless steel strip is cold-rolled to precise dimensional tolerances and formed into seamless coil tubes through a continuous forming process. Multiple forming stations ensure uniform wall thickness and tight dimensional control throughout the coil length.
Step 3 — Solution Annealing & Pickling
The formed coil tube undergoes solution annealing in a controlled atmosphere furnace (typically 1050°C – 1150°C) to restore full austenitic microstructure and relieve cold-work stresses. Subsequent pickling removes oxide scale and surface contaminants, preparing the material for final surface treatment.
Step 4 — Internal Surface Treatment (Electro-Polishing / Passivation)
To achieve the required ultra-smooth internal surface and ultra-low moisture retention, the coil tube undergoes electro-polishing or chemical passivation treatment. This process removes the outermost layer of metal, eliminating surface defects, micro-pores, and adsorbed moisture. The final Ra ≤ 0.1 μm finish minimizes gas adsorption and moisture re-accumulation.
Step 5 — Ultra-High Vacuum (UHV) Baking / Drying
The critical differentiator in this product line is the ultra-dry treatment phase. The coil tube is subjected to high-temperature baking under vacuum or inert gas purge conditions, driving off all residual absorbed and adsorbed moisture. This ensures the internal environment meets the ≤1 ppm moisture specification.
Step 6 — Karl Fischer Moisture Testing & Dew Point Verification
Each production batch undergoes rigorous moisture verification using:
- Karl Fischer Titration: A volumetric or coulometric Karl Fischer method (per ASTM D665 / GB/T 7607) provides quantitative ppm-level moisture measurement of the gas phase within the tube. This is the gold-standard method for trace moisture analysis.
- Capacitive Dew Point Meter: Complementary verification using a high-sensitivity capacitive dew point sensor confirms that the internal dew point is ≤−60°C, correlating to sub-1 ppm moisture levels.
Step 7 — Sealed Packaging & Shipping
Upon passing all cleanliness and moisture verification tests, the coil tube is immediately sealed in nitrogen-purged, moisture-barrier packaging (multi-layer aluminum laminate or vacuum-sealed plastic wrap) within wooden export-grade crates. This packaging maintains the ultra-dry internal condition throughout logistics and storage.
Applications
Primary Applications
- Semiconductor Manufacturing: Distribution of specialty electronic gases (SiH₄, NH₃, HBr, HF, NF₃, Cl₂, HCl, B₂H₆) in wafer fabrication facilities (fabs) where moisture-induced hydrolysis can generate particulate contamination and etch chemistry deviations.
- Photolithography Systems: Gas supply lines for resist processing and lithography equipment requiring ultra-pure, moisture-free gas delivery.
- Chemical Vapor Deposition (CVD) & Physical Vapor Deposition (PVD): Precursor gas delivery lines in thin-film deposition processes where ppm-level moisture can alter film stoichiometry and properties.
- Plasma Etch Systems: Gas supply tubing for etch chambers where moisture contamination leads to fluorine-based byproduct generation and chamber corrosion.
Secondary Applications
- Flat Panel Display (FPD) Manufacturing: Specialty gas distribution in TFT-LCD and OLED production lines.
- Photovoltaic (Solar Cell) Manufacturing: High-purity gas delivery in PECVD and diffusion processes.
- Medical & Pharmaceutical Gas Systems: Where ultra-low moisture content is required for sensitive gas delivery.
- Laboratory Analytical Instrumentation: Carrier gas lines for GC, MS, and other analytical systems requiring dry, contamination-free gas paths.
- Food & Beverage Industry: CO₂ and nitrogen piping where moisture control affects product quality.
Quality Certifications & Compliance
Management System Certifications
- ISO 9001:2015 — Quality Management System
- ISO 14001:2015 — Environmental Management System
- ISO 45001:2018 — Occupational Health & Safety Management System
Product & Process Certifications
- EN 10204 3.1 — Material Test Certificate per European standard
- ASME B36.19M — Compliance for stainless steel tubing dimensions
- ASTM A269 — Standard Specification for Seamless and Welded Austenitic Chromium-Stainless Steel Tubing for Boilers, Heat Exchangers, and Similar Heat Absorbing Applications
- ASTM A213 — Standard Specification for Seamless Austenitic Chromium-Stainless Steel Tubing for High-Service Boilers and Heat Exchangers
- SEMI F57 / SEMI S2 — Semiconductor equipment materials interface and contamination control guidelines (applicable)
Testing & Inspection Protocols
- Moisture Testing: Karl Fischer Titration (ASTM D665) and capacitive dew point measurement on every production batch.
- Chemical Composition Verification: Spectroscopic analysis (OES/PMI) on each heat lot.
- Dimensional Inspection: 100% in-line monitoring of OD, wall thickness, and coil flatness.
- Surface Finish Verification: Surface roughness profilometry per ISO 4287.
- Hydrostatic/Pneumatic Testing: Pressure testing per ASTM A530 for leak-tightness verification.
- Particle Counting: Internal surface particulate assessment per ISO 14644-1 (Class 1–5 achievable).
Traceability
Every coil tube product is fully traceable from raw material mill heat number through all manufacturing stages to final shipment. Customers receive comprehensive documentation including mill test certificates (MTC), moisture test reports (Karl Fischer certificate), dimensional inspection reports, and cleanliness verification records, enabling complete supply chain audit and qualification.
Technical Summary
Wenzhou Jixing Metal Materials Co., Ltd.'s Ultra-Low Moisture Stainless Steel Coil Tube delivers the critical ppm-level moisture control that electronic specialty gas piping demands. Through advanced manufacturing processes, dual-method moisture verification (Karl Fischer titration and dew point metering), and sealed nitrogen-purged packaging, this product eliminates hydrolysis risk vectors that plague standard industrial tubing. The result is a reliable, contamination-free gas distribution solution for the most stringent semiconductor, display, and analytical applications worldwide.