Everything You Need to Know About Alloy 20 Pipe

If you are working in an industry where a corrosive environment is often an issue, alloy 20 pipe is something you should consider. Made of a highly durable alloy that is capable of withstanding corrosive media, alloy pipe is a great choice for industries like the pharmaceutical industry, chemical production, and food processing.

In this blog post, we’ll discuss everything you need to know about alloy 20 to help you determine if it’s the right fit for your business.

What is Alloy 20 Pipe?

Alloy 20 pipe is a corrosion-resistant nickel-iron-chromium alloy designed to resist pitting and chloride ion corrosion. Pitting is the localised corrosion of a metal, and chloride ion corrosion is the result of the exposure of a metal to chloride environments, such as salt and hydrochloric acid.

Alloy 20 Pipe, or Carpenter 20 or Incoloy® 20, is a high-alloy austenitic stainless steel pipe used to handle many corrosive environments. This corrosion-resistant material is resistant to sulfuric acid, phosphoric acid and nitric acid. Its low carbon content helps promote superior resistance to intergranular corrosion and stress corrosion cracking (SCC). It also exhibits good mechanical properties at both elevated and subzero temperatures, making it suitable for cryogenic applications. The alloy’s higher chromium content (minimum of 12%) allows it to be welded easily while providing superior resistance against general pitting and crevice corrosion in water or acidic environments. Its high nickel content also provides excellent thermo-stability compared to other stainless steels like 304L or 316L. Alloy Pipe can be found in the petrochemical industry due to its strength and durability against various concentrations of harsh chemicals such as caustic alkalis.

Composition of Alloy 20 Pipe

Alloy 20 comprises iron, chromium, nickel, copper, molybdenum and niobium, giving it exceptional corrosion resistance. In addition to this, the alloy is also extremely ductile, making it easy to work with during manufacturing and installation.

Benefits of Alloy 20 Pipe

Increased Corrosion Resistance

One of the primary benefits of Alloy 20 pipe is that it offers increased corrosion resistance. This is because Alloy 20 contains chromium, nickel, and molybdenum, which are all elements that offer excellent corrosion resistance. In addition, Alloy pipe is also resistant to pitting and crevice corrosion.

Excellent Weldability

Another benefit of Alloy 20 is that it offers excellent weldability. This is because Alloy 20 contains low carbon content, which helps to prevent carbide precipitation during welding. Additionally, Alloy pipe also has good resistance to post-weld cracking.

Good Formability

Alloy pipe also offers good formability. It can be easily formed into the desired shape without cracking or breaking. Additionally, Alloy 20 can be easily welded and machined, making it versatile for various applications.

Resists Stress Corrosion Cracking

Alloy 20 also resists stress corrosion cracking (SCC). This type of corrosion can occur in certain environments, such as those containing chlorides or other corrosive chemicals. SCC can cause pipes to crack or break, leading to leaks or other problems. By choosing Alloy pipe, you can help to avoid these issues.

Cost-Effective Solution

Finally, Alloy pipe is a cost-effective solution for many applications. This is because Alloy 20 is less expensive than other materials, such as stainless steel, while still offering many of the same benefits. As a result, Alloy 20 pipe is an excellent choice for various projects.

Uses of Alloy 20 Pipe

Alloy 20 can be found in various industries, including the chemical, petrochemical, food, pharmaceutical, and power generation industries. Some common applications include chemical processing vessels, heat exchangers, storage tanks, and piping systems.

Maintenance of Alloy 20 Pipe

While alloy pipe is highly resistant to corrosion, it still needs to be maintained to ensure its longevity. Regular cleaning, inspection, and leak detection are a few of the key maintenance tasks that should be performed to keep alloy 20 pipes in top condition.


In short, alloy 20 pipe is a highly durable and corrosion-resistant solution ideal for industries with common corrosive environments. Made of a composition of iron, chromium, nickel, copper, molybdenum and niobium, alloy 20 has a high tensile and yield strength, making it ideal for a wide range of applications. If you are considering using alloy 20 pipes, perform regular maintenance to ensure their longevity and reliability.