316L / Titanium Hydrogen Electrolyzer Cooling Coil Tube
Product Overview
The Hydrogen Electrolyzer Cooling Coil Tube is a precision-engineered coiled tubing solution designed specifically for the demanding thermal management requirements of modern hydrogen production systems. Manufactured by Wenzhou Jixing Metal Materials Co., Ltd., this product addresses the unique dual-threat environment found in KOH (alkaline) and PEM (Proton Exchange Membrane) electrolyzers, where temperatures range from 60°C to 90°C and high-purity hydrogen is continuously generated.
Unlike conventional industrial coil tubes, this product is engineered to simultaneously resist alkaline electrolyte corrosion and prevent hydrogen permeation—a critical combination of challenges that can compromise both equipment integrity and hydrogen purity. The coil tube serves as an essential heat exchange component, maintaining optimal operating temperatures within the electrolyzer stack while ensuring zero contamination of the produced hydrogen.
Material & Properties
316L Stainless Steel Grade
- Low-carbon austenitic stainless steel with maximum carbon content of 0.03%, providing superior resistance to intergranular corrosion in welding and high-temperature service.
- Molybdenum addition (2.0–3.0%) enhances resistance to pitting and crevice corrosion in alkaline KOH electrolyte environments.
- Excellent hydrogen embrittlement resistance due to stable austenitic microstructure, preventing micro-cracking under prolonged hydrogen exposure.
- Operating temperature range: up to 300°C (well above the 60–90°C process requirement).
- Corrosion resistance: proven performance in 30–40% KOH solutions at elevated temperatures.
Titanium Grade (Ti-Grade 1 / Grade 2 / Gr. 7)
- Exceptional resistance to alkaline corrosion—titanium passivates rapidly in KOH solutions, forming a stable TiO₂ oxide film that provides near-immunity to chemical attack.
- Ultra-low hydrogen permeability—titanium's crystal lattice structure creates an effective barrier against hydrogen diffusion, making it the premium choice for hydrogen purity-critical applications.
- High strength-to-weight ratio enables thinner wall construction without sacrificing mechanical integrity.
- Non-magnetic and non-sparking properties add inherent safety in hydrogen-rich environments.
- Operating temperature range: up to 400°C in non-oxidizing environments.
Key Specifications
| Parameter | Specification |
|---|---|
| Outer Diameter (OD) | Ø6 mm – Ø50 mm (customizable) |
| Wall Thickness | 0.5 mm – 3.0 mm (precision controlled) |
| Coil Inner Diameter (ID) | Ø100 mm – Ø800 mm |
| Coil Length | Up to 500 m per continuous coil |
| Material Grades | ASTM A270 TP316L / ASTM B363 Ti Gr.1 / Gr.2 / Gr.7 |
| Surface Finish | Electropolished (Ra ≤ 0.4 μm) or Mill Finish |
| Operating Temperature | 60°C – 90°C (design margin to 300°C) |
| Operating Pressure | Up to 2.5 MPa (hydrostatic tested at 3.0 MPa) |
| Hydrogen Permeation Rate | < 0.1 mL/(m²·h·atm) for Ti grade; < 0.5 mL/(m²·h·atm) for 316L |
| Corrosion Rate in 30% KOH @ 90°C | < 0.05 mm/year (316L); < 0.01 mm/year (Titanium) |
| Tensile Strength | ≥ 515 MPa (316L); ≥ 275 MPa (Ti Gr.1) |
| Elongation | ≥ 40% (316L); ≥ 20% (Ti Gr.1) |
| Heat Exchange Efficiency | ≥ 95% (with optimized coil geometry) |
| Delivery Form | Continuous coil on wooden/steel spool |
Manufacturing Process
Wenzhou Jixing Metal Materials employs a multi-stage precision manufacturing process to ensure the coil tubes meet the stringent requirements of hydrogen electrolyzer applications:
- Material Selection & Incoming Inspection: Certified raw material coils sourced from accredited mills, with full chemical composition verification and mechanical property testing per ASTM/EN standards.
- Precision Forming: Multi-roller cold forming process maintains dimensional accuracy (±0.05 mm OD tolerance) while preserving the material's metallurgical properties without inducing work hardening.
- Controlled Coiling: CNC-guided coiling ensures uniform coil geometry, consistent pitch, and minimal residual stress throughout the entire coil length.
- Solid Solution Annealing: For 316L grade, annealing at 1050–1100°C with rapid water quenching relieves forming stresses and restores full corrosion resistance and ductility.
- Surface Treatment: Electropolishing removes surface contaminants and creates a smooth, passivated surface that minimizes hydrogen adsorption sites and enhances anti-corrosion performance.
- Hydrogen Permeation Testing: Each batch undergoes accelerated hydrogen permeation testing to verify barrier performance meets specification limits.
- Corrosion Testing: Immersion testing in simulated KOH electrolyte at operating temperatures validates long-term corrosion resistance.
- Hydrostatic Pressure Testing: 100% inline pressure testing at 1.5× working pressure ensures zero-defect delivery.
- Final Inspection & Packaging: Dimensional verification, visual inspection, and protective packaging on corrosion-resistant spools.
Applications
Hydrogen Electrolyzer Systems
- Alkaline (KOH) Electrolyzers: Cooling coils for electrolyte circulation loops, managing thermal load from exothermic electrolysis reactions at 30–40% KOH concentration and 60–90°C operating temperatures.
- PEM Electrolyzers: Anode and cathode side cooling circuits requiring ultra-high hydrogen purity (≥ 99.999%) with zero metal contamination.
- SOEC (Solid Oxide Electrolysis Cell): Auxiliary cooling circuits for intermediate temperature hydrogen production systems.
Additional New Energy Applications
- Fuel cell thermal management systems
- Hydrogen storage and distribution infrastructure cooling
- Green hydrogen production plant balance-of-plant heat exchange
- Electrolyte recirculation and purification systems
Quality Certifications & Standards
- Material Certification: Full mill certificates per EN 10204 3.1/3.2; ASTM A270 (316L), ASTM B363 (Titanium)
- Quality Management: ISO 9001:2015 certified manufacturing process
- Pressure Vessel Compliance: Designed and tested per ASME Section VIII Div.1 / PED 2014/68/EU
- Hydrogen Industry Standards: Compliant with ISO 22734 (hydrogen fuel cell systems) and ISO 14687 (hydrogen permeation testing)
- Corrosion Testing: Verified per ASTM G48 (pitting), ASTM G59 (crevice corrosion), and ASTM G102 (stress corrosion)
- Hydrogen Safety: Tested per ISO 15001 (hydrogen embrittlement) and NACE MR0175 (sulfide stress cracking)
- Third-Party Verification: Available from SGS, Bureau Veritas, or TÜV upon request
Unique Selling Points
Dual-Barrier Design Philosophy: This product uniquely addresses the two most critical failure modes in hydrogen electrolyzer cooling systems—alkaline corrosion and hydrogen permeation—simultaneously through material science optimization and precision manufacturing.
- Dual-Material Option: Customers can select 316L for cost-effective applications or Titanium for maximum performance, with both options rigorously validated for the 60–90°C KOH/PEM environment.
- Zero Hydrogen Contamination: Titanium grade delivers hydrogen permeation rates below 0.1 mL/(m²·h·atm), ensuring electrolyzer hydrogen purity exceeds 99.999% specification.
- Extended Service Life: Corrosion rates below 0.05 mm/year in 30% KOH at 90°C translate to 20+ year operational life, minimizing unplanned maintenance downtime.
- Continuous Coil Delivery: Up to 500 m per coil eliminates field splicing, reducing leak points and improving system reliability.
- Custom Engineering Support: Wenzhou Jixing provides application-specific coil geometry optimization, thermal simulation, and integration guidance for electrolyzer OEMs and EPC contractors.
- Scalable Production: From pilot-plant quantities to utility-scale hydrogen production plants, with consistent quality across all production volumes.
Technical Support & Customization
Wenzhou Jixing Metal Materials Co., Ltd. offers comprehensive technical support including:
- Thermal performance simulation and coil geometry optimization
- Material selection engineering for specific electrolyte compositions and operating conditions
- Custom dimensional configurations to match proprietary electrolyzer designs
- Joint development with hydrogen technology companies for next-generation electrolyzer platforms
- Post-delivery quality traceability and lifetime material performance tracking