Uns N08825 alloy heat exchanger tube

Uns N08825 alloy heat exchanger tube

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Uns N08825 alloy heat exchanger tube

UNS N08825 alloy tubing, commonly known as Incoloy 825 tubing, is a nickel-iron-chromium alloy containing molybdenum, copper, and titanium. It offers excellent resistance to a wide range of corrosive environments and performs well at high temperatures, making it ideal for heat exchanger tubing used in the chemical processing, nuclear power, and oil and gas industries. These tubing can be seamless or welded and manufactured to standards such as ASTM B163 and ASTM B423.

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What is the difference between UNS N06625 and UNS N08825?

Inconel 625 vs. Incoloy 825 (UNS N06625 vs. UNS N08825)
The primary difference between the two materials is their nickel content. Inconel 625 contains at least 58% nickel, while Incoloy 825 has a nickel content between 38% and 46%. This makes 625 more expensive.

 

 

Incoloy 825 heat exchanger tubes offer numerous advantages over other materials. Their exceptional corrosion resistance sets them apart. Incoloy 825 offers excellent resistance to oxidizing and reducing environments, including highly corrosive acids and chloride-containing solutions. This corrosion resistance extends service life, reduces maintenance costs, and minimizes the risk of heat exchanger leaks or failure.

Incoloy 825 maintains its mechanical strength at elevated temperatures, making it suitable for high-temperature applications. This property enables heat exchanger tubes to withstand rigorous operating conditions without compromising structural integrity. The alloy's excellent thermal stability further enhances its reliability and efficiency in heat transfer processes.

Another advantage of Incoloy 825 is its resistance to pitting, crevice corrosion, and stress corrosion cracking. These localized corrosion mechanisms are particularly severe in heat exchangers and can lead to premature failure. Incoloy 825's resistance to these corrosion mechanisms enhances the service life and performance of heat exchanger tubes.

Specification Of Incoloy 825 Heat Exchanger Tube

Incoloy 825 Heat Exchanger Tube Manufacturing Process

Drawing/Floating Process
Pulling a metal bar, rod, or wire through a die to change its surface finish, shape, dimensions, and/or mechanical properties is called floating or drawing. The tube drawing process reduces the outer diameter, inner diameter, and wall thickness of the tube. The advantage of stainless steel tubes lies in the maintenance of their surface integrity.

Continuous Heat Exchanger Tube Mills
Continuous tube mills have revolutionized the production of heat exchanger tubes. Compared to traditional processes, these mills require no forging, welding, or filler metal. This technology allows heat exchanger tubes to be produced continuously, increasing productivity, reducing costs, and improving efficiency.

Continuous Casting
Continuous casting is a significant advancement in heat exchanger tube production. Molten metal is continuously poured into a water-cooled mold, where it solidifies into a continuous billet. This continuous casting technique ensures tubes with improved uniformity and enhanced mechanical properties.

Annealing
During the annealing process, the metal is heated above its recrystallization point and then cooled to room temperature. During the forming process, molecular bonds in metal are strengthened, making it stronger. Annealing restores the metal's ductility.

Immersed Tubing
Immersed tubing is a reduced diameter drawing process. In this process, the tube is drawn through a die without a mandrel. Using a mandrel does not guarantee a good internal surface quality. The angle of the die determines the integrity of the external surface. The die used produces a uniform surface. The tube can be significantly smaller than the original dimensions. Immersed tubing is an ideal choice when cost is a concern.

Inspection and Testing
Before shipping our products to customers, we conduct an inspection process to verify their integrity.

Chemical Composition of Incoloy Alloy 825
Chemical composition of Incoloy Alloy 825 (ASTM B163 – Heat exchanger tube)

Tensile Properties of Incoloy Alloy 825

ASTM Product Specifications
ASTM specifications for Incoloy Alloy 825.

Equivalent Grade Designations

Other international grades that are equivalent to Incoloy Alloy 825.

 

About Gnee Steel

Gnee Steel specializes in the production of various nickel-based alloys. Gnee Steel's product packaging includes steel strapping: Pipes with an outer diameter of 3 inches or less are typically strapped together with polypropylene film to prevent rust during sea transportation, and then secured with steel strapping. Wooden boxes/crates: Pipes are typically packaged in wooden boxes or crates to protect them during transportation, especially those that are longer or have larger diameters. Seaworthy export packaging: Suppliers typically use standard seaworthy export packaging methods, which may include a variety of materials and techniques to protect the pipes during transportation. Tarpaulin packaging: This prevents rainwater, seawater, and other external factors from penetrating the export wooden crates during transportation. Gnee Steel specializes in the production and sale of alloy materials. Gnee Steel's products are widely used in aerospace, chemical, power, automotive, nuclear, and other industries, and we can provide customized alloy material solutions based on customer needs. For alloy material pricing inquiries or customized alloy material solutions, please feel free to contact us for a quote at ss@gneemetal.com