Ultrasonic-Cleaned Internal Surface Stainless Steel Coil Tube
Product Overview
The ultrasonic-cleaned internal surface stainless steel coil tube represents an advanced manufacturing solution developed by Wenzhou Jixing Metal Materials Co., Ltd. This product integrates precision coil tube forming with high-frequency ultrasonic internal cleaning technology, leveraging the cavitation effect (Cavitation Effect) of ultrasonic waves in liquid media to achieve exceptional internal surface cleanliness. The process specifically targets the removal of mechanically embedded micro-particles, achieving a cleanliness level that significantly outperforms conventional chemical-only washing methods. This makes the product suitable for high-purity applications in pharmaceutical, semiconductor, and food-grade processing industries.
Material & Properties
- Base Material: Austenitic stainless steel grades including SUS304, SUS316L, and SUS321 (EN 1.4301, EN 1.4404, EN 1.4541)
- Corrosion Resistance: Excellent resistance to intergranular corrosion, pitting corrosion, and stress corrosion cracking
- Internal Surface Finish: Cleanliness achieved via ultrasonic cavitation; residual particle count reduced to below 0.5 µm threshold
- Formability: Maintains full material ductility post-cleaning; no surface embrittlement from mechanical or chemical attack
- Temperature Resistance: Serviceable from cryogenic temperatures up to 870°C (SUS304) / 925°C (SUS316L)
- Hygienic Compliance: Internal surface meets sanitary-grade requirements equivalent to Ra ≤ 0.4 µm roughness equivalent in cleanliness
Specifications
| Parameter | Specification | Standard / Method |
|---|---|---|
| Tube Configuration | Coil (continuous length) | — |
| Outer Diameter (OD) | Φ3.0 mm – Φ108.0 mm | ASTM A213 / EN 10216-5 |
| Wall Thickness | 0.3 mm – 6.0 mm | ASTM A213 / EN 10216-5 |
| Ultrasonic Frequency | 28 kHz – 40 kHz (standard); 80 kHz – 200 kHz (precision grade) | ISO 11608 |
| Cleaning Medium | Deionized water with surfactant additives (optional) | Internal process specification |
| Internal Cleanliness Level | Particle removal > 99.5% (mechanically embedded particles) | ASTM F88 / ISO 14644 |
| Residual Contaminant Mass | ≤ 0.1 mg/m² (total non-volatile residue) | USP <643> / Ph. Eur. 2.6.12 |
| Coil Length (Typical) | 20 m – 500 m (customizable) | — |
| Delivery Condition | Full Annealed (FA), Solution Annealed (SA) | ASTM A213 |
| End Condition | Plain end, beveled end, or welded end cap | Customer specification |
Manufacturing Process
3.1 Coil Tube Forming
The base coil tube is manufactured through precision cold drawing or seamless piercing processes, followed by full annealing to relieve residual stresses and restore full austenitic microstructure. The coil form is maintained throughout processing to enable continuous inline cleaning.
3.2 Ultrasonic Internal Cleaning
The core differentiating process is the ultrasonic internal cleaning (Ultrasonic Internal Cleaning) step, which employs the following mechanism:
- Transducer Activation: Piezoelectric transducers generate high-frequency mechanical vibrations (28–200 kHz) that propagate through the cleaning liquid medium.
- Cavitation Bubble Formation: Alternating compression and rarefaction cycles create microscopic vacuum bubbles within the liquid that fill the tube's internal bore.
- Implosive Collapse (Cavitation Effect): When these bubbles collapse asymmetrically near the tube wall, they generate localized micro-jets with velocities exceeding 400 m/s and temperatures reaching 5,000 K, producing extreme shear forces at the metal surface.
- Mechanical Particle Dislodgement: The cavitation-driven micro-jets effectively strip mechanically embedded particles—residual metal chips, oxide scale fragments, and grinding debris—that are physically trapped within surface micro-voids and cannot be removed by chemical dissolution alone.
- Rinsing & Drying: A final deionized water rinse removes suspended contaminants, followed by forced hot air drying to prevent water spotting.
3.3 Comparative Advantage Over Conventional Methods
| Method | Mechanism | Limitations |
|---|---|---|
| Chemical Pickling Only | Acid dissolution of oxide layers | Cannot remove mechanically embedded particles; risk of acid residue; environmental concerns |
| Brush / Ball Cleaning | Mechanical abrasion | Introduces new wear debris; inconsistent coverage; potential for surface damage |
| Ultrasonic Cleaning (This Product) | High-frequency cavitation micro-jet implosion | None significant; achieves superior cleanliness without introducing secondary contamination |
3.4 Process Parameters
- Frequency Selection: 28–40 kHz for standard cleaning of tubes ≥ Φ10 mm; 80–200 kHz for precision cleaning of thin-wall tubes (≤ Φ10 mm) requiring finer cavitation intensity
- Power Density: 30–60 W/L (standard); up to 100 W/L for heavily contaminated surfaces
- Processing Temperature: 40°C – 80°C (optimized for cavitation intensity)
- Cycle Time: 15–45 minutes per coil batch (dependent on contamination level and tube geometry)
Applications
- Pharmaceutical & Bioprocessing: High-purity fluid transfer lines, chromatography columns, and bioreactor connections requiring validated cleanliness (USP Class I)
- Semiconductor Manufacturing: Ultra-pure water (UPW) delivery systems and chemical vapor deposition (CVD) gas lines where particulate contamination must be minimized to sub-micron levels
- Food & Beverage Processing: Dairy, beverage, and juice processing lines requiring sanitary-grade internal surfaces compliant with FDA and 3-A Sanitary Standards
- Chemical Processing: Transfer lines for aggressive chemical media where internal cleanliness prevents catalytic contamination of product streams
- Medical Devices: Tubing for dialysis systems, infusion pumps, and implantable device manufacturing
- Heat Exchangers & Condensers: Enhanced thermal performance due to absence of internal fouling particles that act as nucleation sites for scale formation
Quality Certifications
- ISO 9001:2015 — Quality Management System certification
- ISO 14001:2015 — Environmental Management System certification
- EN 10204 3.1 — Inspection Certificates (Material Test Reports)
- ASTM A213 / ASME SA-213 — Standard specification for seamless austenitic stainless steel boiler, heat-exchanger, and similar heat-transfer service tubes
- EN 10216-5 — Heat-resistant, hermetic, and mechanical tubes and pipes — Technical delivery conditions
- ISO 11608 — Ultrasonic testing of tubes and pipes — General guidance
- USP <643> / Ph. Eur. 2.6.12 — Elemental impurities compliance for pharmaceutical applications
- ISO 14644 — Cleanroom cleanliness classification compliance for semiconductor-grade applications
- 3-A Sanitary Standards — Food-grade processing equipment compliance
- CE Marking — European Conformity for pressure equipment (PED 2014/68/EU)
Unique Selling Points
Superior Internal Cleanliness: The ultrasonic cavitation process achieves a level of internal surface cleanliness unattainable through chemical pickling alone, specifically targeting and removing mechanically embedded particles that conventional methods leave behind.
Non-Damaging Process: Unlike mechanical brushing or ball cleaning, ultrasonic cleaning does not introduce secondary wear debris or cause surface work-hardening, preserving the integrity of the stainless steel microstructure.
Process Reproducibility: Ultrasonic parameters (frequency, power, duration, temperature) are precisely controlled and documented, ensuring batch-to-batch consistency in cleanliness outcomes.
Environmental Compliance: The process minimizes chemical consumption and eliminates the need for aggressive acid pickling, reducing environmental impact and operator exposure to hazardous substances.
Customizable Coil Configuration: Available in a wide range of diameters, wall thicknesses, and coil lengths to meet specific project requirements.