When you are dealing with the most aggressive environments in chemical processing—specifically high-temperature alkali and acid handling—material selection is not just a specification; it is a safety and financial decision. At DLX, we specialize in providing high-performance tubing solutions that stand up to these challenges. Our Nickel 201 Welded Tube is engineered specifically for systems that demand exceptional corrosion resistance, high thermal conductivity, and long-term reliability in extreme conditions.
Nickel 201 (UNS N02201) is the low-carbon version of commercially pure nickel. While its cousin, Nickel 200 , is a fantastic material, it has limitations when things get hot. The secret behind DLX’s Nickel 201 is the controlled maximum carbon content of 0.02%. This seemingly small adjustment makes a world of difference. It prevents "graphitization"—a phenomenon where carbon precipitates at grain boundaries in high temperatures—which can lead to catastrophic failure in equipment handling molten caustic soda or hot acids .
Whether you are building evaporators for the chlor-alkali industry, piping for hot hydrofluoric acid, or heat exchangers in a aggressive chemical plant, DLX delivers welded tube that you can depend on.
For more details, pls directly contact us.
Chemical Composition
| Grade | Nickel (Ni)+ Cobalt (Co) | Copper (Cu) | Silicon (Si) | Manganese (Mn) | Carbon (C) | Magnesium (Mg) | Sulfur (S) | Phosphorus (P) | Iron (Fe) |
| 99.9% | ≤0.015 | ≤0.03 | ≤0.002 | ≤0.01 | ≤0.01 | ≤0.001 | ≤0.001 | ≤0.04 | |
| 99.6% | 0.1 | 0.1 | 0.05 | 0.1 | 0.1 | 0.005 | 0.002 | 0.1 |
Physical & Mechanical Properties
| Grades | N4/Ni201 | N6/Ni200 |
| Density | 8.9g/cm³ | 8.9g/cm³ |
| Melting Point | 1455°C | 1445-1470℃ |
| Coefficient of Thermal Expansion | 13.0µm/m·°C | 13.3×10⁻⁶/℃ |
| Thermal Conductivity | 10.1W/m·K | 90.7 W/m·K |
| Electrical Resistivity | 0.103×10⁻⁶Ω·/m (at 20℃) | |
| Electrical Conductivity | 14.6% IACS | |
| Tensile Strength | ≥450MPa | ≥450 MPa |
| Yield Strength | ≥200MPa | ≥150 MPa |
| Elongation at Break | ≥40% | ≥40% |
| Hardness | ≤150 |
Product Specifications: DLX Nickel 201 Welded Tube
To help you specify the right material for your project, here is a quick comparison of the key data points for our Nickel 201 Welded Tube versus a generic annealed condition.
| Parameter | DLX Nickel 201 Welded Tube (Typical) | Industry Standard / Notes |
|---|---|---|
| UNS Designation | N02201 | Compliant with ASTM B/ASME SB |
| Chemical Composition | ||
| Nickel (Ni) | 99.0% min | Ensuring maximum purity |
| Carbon (C) | 0.02% max | Key differentiator for high-temp use |
| Iron (Fe) | 0.40% max | Trace elements controlled tightly |
| Mechanical Properties | ||
| Tensile Strength | 55,000 - 65,000 psi (380 - 450 MPa) | Fully annealed for optimal formability |
| Yield Strength (0.2% offset) | 15,000 - 25,000 psi (105 - 170 MPa) | Low yield allows for easy bending |
| Elongation | 40% - 50% | Excellent ductility for rolling into tubesheets |
| Physical Properties | ||
| Density | 0.321 lb/in³ (8.89 g/cm³) | |
| Thermal Conductivity | ~ 70 W/m·K (at 20°C) | Excellent for heat exchangers |
| Melting Range | 2615 - 2635 °F (1435 - 1445 °C) | |
| Key Feature | Resists Graphitization up to 600°F+ | Outperforms Nickel 200 in sustained heat |
Industry Analysis and Application of Nickel 201 Welded Tube
The global demand for high-performance nickel alloy tubes is on a steady rise, driven by stricter environmental regulations and the need for higher efficiency in chemical processing . Industries are pushing temperatures and pressures higher to increase yields, which puts older materials like stainless steel and even Nickel 200 at risk. This is where the market for specialized solutions like the Nickel 201 welded tube is expanding.
We are seeing significant growth in the chlor-alkali sector, particularly in regions expanding their production of caustic soda. As a critical material for vinyls, alumina, and soaps, the production of caustic soda relies heavily on equipment that won't corrode or contaminate the product. Nickel 201 is the gold standard here .
Furthermore, the push for cleaner energy involves handling aggressive media. Whether it is the production of "green" hydrogen via electrolysis or the handling of molten salts in concentrated solar power, the corrosion resistance and thermal properties of Nickel 201 make it an increasingly vital component in the energy transition.
Application Deep Dive
The Chlor-Alkali Evaporator:
Imagine a system concentrating 50% caustic soda up to 73% or even anhydrous. Temperatures climb towards 200°C (400°F). In this environment, ordinary stainless steel would disintegrate rapidly. DLX Nickel 201 welded tube is often used in the heat-exchanger sections of these evaporators. Its high thermal conductivity ensures efficient heat transfer (saving energy costs), while its resistance to caustic embrittlement ensures the tubes remain intact and leak-free for years .
Handling Hydrofluoric Acid (HF):
HF is one of the most dangerous and corrosive industrial chemicals. It etches glass and destroys silicon-based materials. Nickel 201 is one of the few materials that can handle anhydrous HF and its aqueous solutions with grace. DLX welded tubes provide the safe conduit for this aggressive acid in alkylation units and fluorocarbon production plants.
High-Temperature Organics:
In the production of fatty acids and synthetic fibers, process streams can be both acidic and hot. Nickel 201's resistance to organic acids at elevated temperatures, combined with its resistance to contamination (it won't catalytically degrade some organic compounds), makes it a preferred material for reactors and piping .
The DLX Advantage: A Comparative Look
When you are choosing a supplier for critical service tubing, you need more than just a material certificate. You need a partner who understands the application. At DLX, we differentiate ourselves through meticulous quality control and customer-centric service. Here is how we stack up against a hypothetical standard supplier (let's call them "Standard Alloy Corp").
Material Sourcing & Purity:
Standard Alloy Corp: May source from various mills, leading to batch-to-batch variation.
DLX Advantage: We partner exclusively with top-tier mills that guarantee the low-carbon chemistry (C ≤0.02%) and high purity (Ni 99%+) required for high-temperature service. We know the melt history of our metal.
Manufacturing Process:
Standard Alloy Corp: Relies on generic welding schedules.
DLX Advantage: Our welded tube is produced using automated high-frequency induction welding, followed by precise bead trimming. We then subject the tube to a full solution anneal in a controlled atmosphere furnace. This ensures the weld zone recrystallizes, matching the grain structure of the base metal and restoring full corrosion resistance. We don't just weld it; we metallurgically homogenize it .
Quality Assurance:
Standard Alloy Corp: Provides standard mill certificates.
DLX Advantage: Every length of DLX Nickel 201 welded tube is rigorously tested. This includes 100% eddy current testing for flaws, a full review of mechanical properties, and pressure testing where required. We offer a 100% traceability guarantee from the melt to your receiving dock.
Inventory & Logistics:
Standard Alloy Corp: Long lead times; high minimum order quantities.
DLX Advantage: We maintain a deep inventory of Nickel 201 welded tube in various sizes, from small diameter instrumentation tubing to large OD process pipe. This means we can ship quickly, often within a week, helping you keep your project on schedule. We are happy to cut to exact lengths to reduce your waste.
Technical Support:
Standard Alloy Corp: "Here is the spec sheet."
DLX Advantage: Our team asks, "What temperature? What concentration? What pressure?" We provide real engineering support to help you select the right wall thickness and temper. We want to make sure the tube succeeds in your specific system.
In the battle against high-temperature corrosion, DLX stands with you. Our Nickel 201 Welded Tube represents the perfect blend of metallurgical science and precision manufacturing. By choosing DLX, you are not just buying a pipe; you are investing in reliability, safety, and performance.
For more details, pls directly contact us.
About Us:
Our 12,000㎡ factory is equipped with complete capabilities for research, production, testing, and packaging. We strictly adhere to ISO 9001 standards in our production processes, with an annual output of 1,200 tons. This ensures that we meet both quantity and quality demands. Furthermore, all products undergo rigorous simulated environment testing including high temperature, high pressure, and corrosion tests before being dispatched, ensuring they meet customer specifications.
For all our clients, we offer timely and multilingual after-sales support and technical consulting, helping you resolve any issues swiftly and efficiently.
Client Visits
Building Stronger Partnerships
We support all kinds of testing:
When your next project calls for a material that can handle the heat and the aggression of caustic and acid, call DLX. We are ready to deliver.
1. What makes Nickel 201 different from Nickel 200, and why should I care?
Great question. Both are commercially pure nickel, but the difference is in the carbon. Nickel 200 has a carbon content of up to 0.15%. When you operate above 300°C (approx. 600°F), that carbon can turn into graphite along the grain boundaries, making the metal brittle and weak. Nickel 201, which we use at DLX, has a max carbon of 0.02%. This eliminates the risk of graphitization, making it the safe, reliable choice for continuous high-temperature service .
2. Can DLX Nickel 201 welded tube really handle both acids and alkalis?
Absolutely. It excels in "reducing" environments. In the chemical industry, that means it is a top performer against hot alkalis like sodium hydroxide (caustic soda) and potassium hydroxide, even in molten states. On the acid side, it stands up beautifully to non-oxidizing acids like hydrochloric, hydrofluoric, and phosphoric acids . It is the "go-to" material when your process swings between these harsh media.
3. Is a "welded" tube as strong as a seamless tube for these applications?
At DLX, we ensure our welded tube doesn't just meet the standard—it sets it. Modern welding techniques, combined with post-weld treatments, create a bond that is just as strong as the base metal. For Nickel 201, which has excellent welding characteristics, the weld zone actually becomes homogenous with the rest of the tube. Welded tube also offers superior dimensional accuracy and surface finish consistency, which is critical for heat transfer efficiency .
4. What are the mechanical properties of the DLX Nickel 201 welded tube?
In its annealed state—which is how we ship most of our stock for forming applications—you can expect a tensile strength of around 380 MPa (55,000 psi) minimum and a yield strength around 105 MPa (15,000 psi). But the real star is the ductility. With an elongation of about 40% or more, it is incredibly easy to bend, flare, or roll into tubesheets without cracking .
5. How does Nickel 201 perform against Chloride Stress Corrosion Cracking?
This is where nickel alloys beat standard stainless steels every time. Stainless steels can fall victim to chloride stress corrosion cracking (SCC) in hot, chloride-rich environments. Thanks to its high nickel content (over 99%), DLX Nickel 201 has near-immunity to SCC. If you are dealing with magnesium chlorides or calcium chlorides at elevated temps, this is your material .
6. What industries typically use this type of tubing?
You will find DLX Nickel 201 tubes hard at work in:
Chlor-Alkali Plants: For the production and concentration of sodium hydroxide .
Chemical Processing: In vessels and piping handling fatty acids, phenols, and hydrofluoric acid .
Heat Treatment: As radiant tubes or muffles where resistance to carburizing atmospheres is needed .
Food Processing: In equipment making fatty acids or handling edible oils where product purity is vital .
7. What are the limitations I need to watch out for?
Nobody likes surprises. Nickel 201 is not suitable for strongly oxidizing conditions. So, keep it away from concentrated nitric acid or oxidizing salt solutions like ferric or cupric chloride. Also, avoid high-temperature sulfur-bearing fumes; they can cause embrittlement .
8. Why should I source my Nickel 201 tubing from DLX?
Because at DLX, we don't just sell metal; we provide peace of mind. We source our raw materials with strict traceability, ensuring the low-carbon content is locked in. Our welding process is automated and monitored to ensure full penetration and consistency. Plus, we stock a wide range of diameters and wall thicknesses, ready for quick delivery. We partner with you to ensure the material performs in your specific application.
