Incoloy 825 Supplier | Bar, Tube, Plate - Hangbo Alloy
Date: 2024年11月18日 Categories: All Products、Incoloy Views: 2211
Shanghai Hangbo Alloy Group Co., Ltd. is a specialized supplier of Incoloy 825 (UNS N08825 / W.Nr. 2.4858). This nickel-iron-chromium alloy is designed to provide exceptional resistance to many corrosive environments, particularly where sulfuric and phosphoric acids are present.
ASTM Standards & Specifications
- ASTM B423: Standard Specification for Nickel-Iron-Chromium-Molybdenum-Copper Alloy Seamless Pipe and Tube.
- ASTM B424: Standard Specification for Nickel-Iron-Chromium-Molybdenum-Copper Alloy Plate, Sheet, and Strip.
- NACE MR0175: Certified for sour gas service in oil and gas production.
Chemical Composition (ASTM B423/B424)
| Element | Ni | Fe | Cr | Mo | Cu | Ti |
|---|---|---|---|---|---|---|
| Min (%) | 38.0 | 22.0 | 19.5 | 2.5 | 1.5 | 0.6 |
| Max (%) | 46.0 | - | 23.5 | 3.5 | 3.0 | 1.2 |
Mechanical Properties
| Property | Tensile Strength (min) | Yield Strength (0.2% Offset, min) | Elongation (min) |
|---|---|---|---|
| Value | 85 ksi (586 MPa) | 35 ksi (241 MPa) | 30% |
Material Characteristics & Applications
Incoloy 825 is an iron-base nickel alloy that shares many characteristics with Inconel 625 but is more cost-effective for applications where iron-based alloys are suitable. The titanium addition stabilizes the alloy against intergranular corrosion.
- Chloride Resistance: Outstanding resistance to chloride-ion stress-corrosion cracking.
- Acid Resistance: Excellent performance in sulfuric and phosphoric acids.
- Applications: Oil and gas well piping, nuclear fuel reprocessing, acid production, and pollution-control equipment.
Global Project Case: North Sea Oil Field Heat Exchangers
Scenario: An offshore oil platform in the North Sea faced recurring failures in its sea-water-cooled heat exchangers due to pitting and stress corrosion cracking from the high-chloride environment.
Solution: The operator replaced the existing stainless steel bundles with Incoloy 825 tubes (ASTM B163/B423). Hangbo Alloy provided high-precision seamless tubes for this project.
Service Performance: The Incoloy 825 heat exchangers have been operating for over 8 years without any reported corrosion issues, significantly reducing maintenance costs and downtime.
Pros, Cons & FAQ
Pros
- Excellent resistance to stress corrosion cracking.
- Good weldability and fabricability.
- High stability in acidic environments.
Cons
- Not as strong as Inconel 625 at extremely high temperatures.
- Limited resistance to highly oxidizing nitric acid.
FAQ
Q: Is Incoloy 825 suitable for sulfuric acid service?
A: Yes, Incoloy 825 is specifically designed for resistance to sulfuric acid. The addition of copper enhances its performance in a wide range of sulfuric acid concentrations and temperatures, up to roughly 40% concentration at boiling points.
Q: Does Incoloy 825 resist pitting in seawater?
A: While Incoloy 825 offers good resistance to general corrosion and pitting, it is primarily intended for industrial chemical and oil/gas applications. For stagnant seawater environments, higher-molybdenum alloys like Inconel 625 may be preferred, but 825 performs well in flowing seawater conditions.
Q: What is the role of Titanium in Incoloy 825?
A: Titanium is added to stabilize the alloy against intergranular corrosion. It combines with carbon during heat treatment to form titanium carbides, preventing the precipitation of chromium carbides at the grain boundaries, which preserves the alloy's corrosion resistance in the as-welded condition.
Q: Can Incoloy 825 be used in sour gas (H2S) environments?
A: Yes, Incoloy 825 is NACE MR0175 certified. It is highly resistant to sulfide stress cracking and is widely used for downhole tubing, well-head components, and valves in sour oil and gas production.
Q: What is the difference between Incoloy 825 and 800?
A: Incoloy 825 has added molybdenum and copper, making it much more resistant to corrosion in aqueous environments compared to Incoloy 800.
Internal Links to Related Alloys
- Inconel 625 - For higher strength and deep-sea subsea applications.
- Incoloy 800 - For high-temperature structural applications.
- Invar 36 - For low thermal expansion requirements.
- Incoloy 825 Chemical Process Guide - Sulfuric, Phosphoric & Seawater Applications - Technical application guide.
- Incoloy 825 vs 316L Stainless Steel - When to upgrade for corrosion resistance.
