What are Duplex Stainless Steel Pipes, and Why are They a Popular Choice for Marine Applications?

What are Duplex Stainless Steel Pipes, and Why are They a Popular Choice for Marine Applications?

Are you looking for a durable, cost-effective solution for piping in marine applications? Duplex stainless steel pipes may be the perfect option to consider. As a material designed with corrosion resistance and strength at the forefront, duplex stainless steel has outstanding advantages over other types of metals in marine installations. Not only are these components popular amongst professionals due to their strength and efficiency, but they can also help reduce costs significantly by providing a long-term solution that improves system performance and saves time in maintenance. Read on to find out why duplex stainless steel pipes are an increasingly popular choice in maritime projects worldwide.

Duplex Stainless Steel

Duplex stainless steel pipes are hybrid alloys made from chromium, molybdenum, and other metals. These pipes are incredibly durable and corrosion-resistant due to their high alloy content. As the name implies, duplex refers to the two distinct structures of the metal itself: ferritic and austenitic. Ferritic metals possess higher strength but less corrosion resistance than austenitic metals; however, this combination provides Duplex stainless steel with superior properties, such as enhanced ductility and toughness, compared to standard stainless steel. Additionally, Duplex stainless steel pipes can be formed into various shapes, making them an ideal choice for a wide range of applications, including petrochemical processing, marine service environments, food production equipment, and chemical tankers, among many others.

Corrosion Resistance

Duplex stainless steel pipes are manufactured using a combination of austenite and ferrite stainless steel, offering superior corrosion resistance. This type of piping is known for its high yield strength, good mechanical properties, and excellent weldability. The material’s dual-phase microstructure also provides duplex stainless steel with superior tensile strength, pitting resistance equivalent (PRE), stress corrosion cracking resistance (SCC), and improved intergranular corrosion resistance compared to conventional austenitic steels. Its unique composition allows it to be used in harsh environments where traditional carbon steels may otherwise fail due to the effects of chlorine-induced stress corrosion cracking or sulfide stress cracking.

Strength and Durability

Duplex stainless steel pipes are corrosion-resistant and contain equal amounts of chromium, molybdenum, and nickel. They have a higher yield strength than traditional austenitic stainless steel pipes and provide improved resistance to localized corrosion such as pitting, crevice corrosion, stress cracking, and intergranular attack. Their increased durability makes them suitable for corrosive environments that other metals cannot withstand. Duplex stainless steel is also renowned for its excellent mechanical properties at high temperatures and impressive strength-to-weight ratios.

Low Thermal Expansion

Duplex stainless steel pipes have high mechanical strength and excellent corrosion resistance. They are super duplex grade pipes often used in highly corrosive industrial environments and can handle extreme temperatures due to their low thermal expansion coefficient. This means these pipes remain dimensionally stable under varying temperatures, making them ideal for applications such as heat exchangers, condensers, boilers, power plants, and petrochemical piping systems. Their unique composition consists of two different components – austenitic (nickel-chromium-manganese) and ferritic (iron-chromium) – they offer great strength even at higher temperatures than traditional stainless steels.

Reduced Lifecycle Cost

Duplex stainless steel pipes’ lifespan is significantly longer than traditional stainless steel or carbon steel pipes, which can reduce maintenance and replacement costs. These pipes’ superior strength and corrosion resistance lead to less frequent repairs, longer service life, reduced downtime, and lower overall operational costs.


Duplex stainless steel pipes offer exceptional corrosion resistance, mechanical properties, and durability, making them well-suited for marine applications. With their ability to withstand severe and harsh conditions, these pipes are the choice of material for various marine applications. Duplex stainless steel pipes’ long-term durability and low lifecycle costs make them an excellent investment for any marine piping system. A Duplex stainless steel pipe is the go-to solution if you require a material that can withstand corrosive and harsh marine environments.