Incoloy 825 Nickel Alloy Coil Tube for Acid-Resistant Applications
Wenzhou Jixing Metal Materials Co., Ltd. is proud to present its premium Incoloy 825 Coil Tube—a high-performance nickel-iron-chromium-molybdenum-titanium alloy tubing solution engineered for the most demanding corrosive environments. Supplied in continuous coil form, this product delivers exceptional resistance to sulfuric acid, phosphoric acid, and a wide range of aggressive chemical media, making it an indispensable material for acid processing, hydrometallurgical operations, and thermal exchange systems.
Product Overview
Incoloy 825 Coil Tube represents the pinnacle of corrosion-resistant tubing technology within the nickel-based alloy family. Manufactured to stringent international standards, this coil tube combines outstanding resistance to both oxidizing and reducing acids with excellent mechanical properties across a broad temperature range. The continuous coil configuration offers significant advantages over straight-length tubing, including reduced welding joints, improved material utilization, and greater flexibility in downstream fabrication and installation.
Designed and supplied by Wenzhou Jixing Metal Materials Co., Ltd., this product meets the rigorous demands of chemical processing, mining, and energy sectors where material integrity and long service life are non-negotiable requirements.
Material & Properties
Chemical Composition (Typical)
Incoloy 825 is a modified austenitic nickel-iron-chromium alloy with molybdenum and titanium additions that confer superior resistance to a wide spectrum of corrosive media. The titanium addition enhances resistance to intergranular corrosion and improves strength at elevated temperatures.
- Nickel (Ni): Balance (minimum 20.0%) — primary alloying element providing fundamental corrosion resistance
- Iron (Fe): 22.0–28.0% — enhances mechanical strength and structural integrity
- Chromium (Cr): 22.0–25.0% — forms a stable passive oxide layer for oxidation resistance
- Molybdenum (Mo): 2.5–3.5% — critical addition for resistance to reducing acids and pitting
- Titanium (Ti): 0.5–1.0% — stabilizer that prevents sensitization and intergranular attack
- Carbon (C): ≤ 0.08% — low carbon content for enhanced weldability and corrosion resistance
Key Mechanical & Physical Properties
- Corrosion Resistance: Excellent resistance to sulfuric acid (H₂SO₄) and phosphoric acid (H₃PO₄) across a wide range of concentrations and temperatures
- Temperature Range: Suitable for service from cryogenic temperatures up to approximately 600°C (1,112°F)
- Tensile Strength: ≥ 550 MPa (80 ksi) at room temperature
- Yield Strength: ≥ 240 MPa (35 ksi) at 0.2% offset
- Elongation: ≥ 30% in 50 mm gauge length
- Density: 8.14 g/cm³
- Thermal Conductivity: 11.4 W/(m·K) at 100°C
Specifications
| Parameter | Specification |
|---|---|
| Material Grade | Incoloy 825 (UNS N08825 / Alloy 825) |
| Alloy System | Ni-Fe-Cr-Mo-Ti Nickel-Based Alloy |
| Product Form | Coil Tube (Continuous Coil) |
| Outer Diameter | 6.0 mm – 50.8 mm (¼" – 2") |
| Wall Thickness | 0.5 mm – 3.0 mm (0.020" – 0.118") |
| Coil Inner Diameter | Customizable (typical range: 150 mm – 600 mm) |
| Coil Length | Continuous coil; custom lengths available upon request |
| Manufacturing Method | Seamless / Welded (per customer specification) |
| Surface Finish | Mill finish, polished, or passivated |
| Applicable Standards | ASTM B409, ASTM B163, AMS 5509, EN 10217 |
| Key Corrosion Resistance | Sulfuric acid (H₂SO₄), Phosphoric acid (H₃PO₄) |
| Primary Applications | Acid washing equipment, Hydrometallurgy, Condensers |
Manufacturing Process
The production of Incoloy 825 Coil Tube at Wenzhou Jixing Metal Materials Co., Ltd. follows a rigorous, multi-stage manufacturing process to ensure consistent quality and dimensional accuracy:
- Raw Material Selection: Virgin nickel, iron, chromium, molybdenum, and titanium ingots are sourced from certified suppliers and verified through spectroscopic analysis prior to melting.
- Vacuum Arc Remelting (VAR) / Electro-Slag Remelting (ESR): The alloy is melted under controlled vacuum or slag conditions to minimize impurities, ensure uniform composition, and achieve superior metallurgical quality.
- Hot Rolling & Extrusion: The remelted ingot is hot-rolled and extruded into a seamless tube billet or pipe blank with precise dimensional control.
- Cold Drawing / Rolling: The hot-worked tube is cold-drawn or cold-rolled through precision dies to achieve the final outer diameter, wall thickness, and coil configuration with tight tolerances.
- Solution Annealing: The coil tube is solution-annealed at 1050–1150°C followed by controlled cooling to dissolve carbides, restore full corrosion resistance, and achieve the desired soft temper mechanical properties.
- Pickling & Passivation: The surface is acid-pickled to remove oxide scale, followed by passivation treatment to establish a stable chromium oxide protective layer.
- Coiling: The processed tube is wound onto precision coils using automated coiling equipment to ensure uniform tension and prevent deformation or surface damage.
- Quality Inspection & Testing: Every coil undergoes comprehensive inspection including dimensional verification, chemical composition analysis, mechanical testing, hydrostatic pressure testing, and non-destructive examination (eddy current or ultrasonic).
Applications
Incoloy 825 Coil Tube is specifically engineered for service in highly corrosive environments where conventional stainless steels and even many specialty alloys would suffer rapid degradation. Its principal application areas include:
Acid Washing & Cleaning Equipment
The exceptional resistance of Incoloy 825 to sulfuric acid and phosphoric acid makes it the material of choice for components in acid washing systems, acid regeneration plants, and chemical cleaning equipment. Coil tube configurations are particularly advantageous for constructing heat exchangers and heat recovery units within acid processing circuits.
Hydrometallurgical Processing
In mining and metallurgical operations, Incoloy 825 Coil Tube is used extensively in leaching tanks, solvent extraction circuits, and acid recovery systems. Its ability to withstand mixed-acid environments—including combinations of sulfuric, phosphoric, and hydrochloric acids—ensures long service life in extractive metallurgy operations for copper, nickel, cobalt, and rare earth processing.
Condensers & Heat Exchangers
The combination of corrosion resistance and adequate thermal conductivity makes Incoloy 825 Coil Tube ideal for condensers operating in acid-laden atmospheres. Applications include sulfuric acid plant condensers, acid recovery condensers, and evaporative coolers in chemical processing facilities. The coil form facilitates efficient compact heat exchange designs with minimal connection points.
Additional Applications
- Chemical processing equipment handling mixed acid solutions
- Waste acid treatment and recovery systems
- Phosphoric acid production equipment
- Environmental scrubbers and emission control systems
- Seawater heat exchangers in chemical plants
Quality Certifications
Wenzhou Jixing Metal Materials Co., Ltd. maintains a comprehensive quality management system and holds the following certifications and complies with the following standards:
- ISO 9001:2015 — Quality Management System certification ensuring consistent product quality and process control
- ISO 14001 — Environmental Management System certification
- Material Certifications: Full chemical composition and mechanical property test reports provided with each shipment (EN 10204 3.1 certification available)
- Standards Compliance: ASTM B409 (seamless tube), ASTM B163 (welded tube), AMS 5509, EN 10217
- Third-Party Inspection: Available upon request through recognized inspection bodies (SGS, BV, Lloyd's, etc.)
Unique Selling Points
Why Choose Wenzhou Jixing Incoloy 825 Coil Tube:
- Superior Acid Resistance: Unmatched performance in sulfuric and phosphoric acid environments where 304, 316L, and even Hastelloy alloys may prove insufficient at certain concentrations and temperatures.
- Coil Configuration Advantage: Continuous coil supply eliminates the need for field welding of straight lengths, reducing potential leak points, lowering installation labor costs, and improving overall system reliability.
- Wide Specification Range: Available in a broad range of diameters and wall thicknesses to suit diverse application requirements—from small-bore instrumentation tubing to large-diameter process coils.
- Customization Capability: Custom coil diameters, lengths, and surface finishes available to meet specific project requirements.
- Proven Track Record: Trusted by chemical processors, mining companies, and engineering firms worldwide for critical acid service applications.
- Full Traceability: Every coil is traceable from raw material to finished product, with complete documentation supporting procurement, installation, and maintenance requirements.
Technical Support & Ordering
Wenzhou Jixing Metal Materials Co., Ltd. provides comprehensive technical support including material selection guidance, application engineering consultation, and corrosion resistance assessment for specific operating conditions. Contact our sales and engineering team for detailed quotations, sample provision, and project-specific technical documentation.
For inquiries regarding Incoloy 825 Coil Tube or other nickel-based alloy products, please contact Wenzhou Jixing Metal Materials Co., Ltd. directly to discuss your project requirements and receive a tailored solution.