Duplex Steel Pipe & Tube

Duplex stainless steel (DSS) is featured with structure of two phases (¦Á and ¦Ã) and has characteristics of both ferritic and austenitic stainless steel. It has good corrosion resistance and high strength. It is alloyed with 18%-28% Cr and 3%-10% Ni in the condition of low C. Some steels also contain the alloy elements such as Mo, Cu, Nb, Ti and N, etc.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

2205 duplex stainless steel is a cost effective solution for many applications where the 300 series stainless steels are susceptible to chloride stress corrosion cracking. Stress corrosion cracking occurs when stainless steels are subjected to tensile stress, while in contact with solutions containing chlorides. Increasing temperatures also increase the susceptibility of stainless steels to stress corrosion cracking.

The combination of high strength, corrosion resistance and moderate weldability has many benefits but also bring disadvantages and limitations. High strength is a disadvantage when forming and machining. The higher strength also means that the metal is less ductile than austenitic grades. This means that these steels are not good when the goods being produce require any degree of complex forming. It is also worth bering in mind that evemn if the item can be formed in duplex steel greater forces are required. The metallurgy of duplex stainless steels is much more complex than for austenitic or ferritic steels whith the result that they are more complex and therefore expensive to produce. Howver the lower quantity of nickel in them as compared to austenitic grades does help to keep the cost down and reduce price volatility.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

Super Duplex has all the benefits of other duplex steels, specifically the strength benefits of their biphasic structural composition of equal parts austenitic and ferritic stainless steel. This microstructure makes all duplex steels around twice as strong as regular single structure ferritic or austenitic steels, but Super Duplex has a higher chromium and molybdenum content, giving it considerably increased resistance to corrosion than its counterparts.

Alloy 2205 provides pitting and crevice corrosion resistance superior to 316L or 317L austenitic stainless steel tube in almost all corrosive media. It also has high corrosion and erosion fatigue properties as well as lower thermal expansion and higher thermal conductivity than austenitic.

The combination of chromium, molybdenum and nitrogen convey the good resistance of 2205 to chloride pitting and crevice corrosion. This resistance is extremely important for services such as marine environments, brackish water, bleaching operations, closed loop water systems and some food processing applications. The high chromium, molybdenum and nitrogen contents of 2205 provide corrosion resistance superior to common stainless steels, such as, 316L and 317L in most environments.

While Duplex 2205 is the most common duplex product we supply, we can also deliver Duplex 2304 and Duplex 2207 with reduced lead times as these alloys are stocked. Alloy 2205 (UNS S32305/S31803) is a 22% chromium, 3% molybdenum, 5-6% nickel, nitrogen alloyed duplex stainless steel pipe with high general, localized, and stress corrosion resistance properties in addition to high strength and excellent impact toughness.

Duplex pipes are stainless pipes containing the high amount of chromium and minimum amount of nickel. Duplex pipes provide great strength and resistance to corrosive environments. Duplex pipes are used in desalination plants, heat exchangers, and marine processes.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

ASTM A789 A789M Covers Grades of nominal wall thickness, stainless steel tubing for services requiring general corrosion resistance, with particular emphasis on resistance to stress corrosion cracking. These steels are susceptible to embrittlement if used for prolonged periods at elevated temperatures.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

Compared with ferritic stainless steel and austenitic stainless steel, duplex stainless steel pipe has good welding performance. It is neither like the welding heat affected zone of ferritic stainless steel, because of the grain coarsening, the plastic toughness is greatly reduced, nor like austenitic stainless steel, it is more sensitive to welding hot cracks.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

The dual phase steel / super duplex steel stainless steel pipe is a kind of stainless steel with high strength and high corrosion resistance, which has the properties of austenitic stainless steel and ferritic stainless steel. Generally, when the carbon content is low, the Cr content is 18% ~ 28%, and the Ni content is 3% ~ 10%. Some steels also contain Mo, Cu, Nb, Ti, N and other alloy elements.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

Compared with ferrite, it has higher plasticity and toughness, no room temperature brittleness, significantly improved intergranular corrosion resistance and welding performance, and maintained 475 ¡æ brittleness, high thermal conductivity and Superplasticity of ferritic stainless steel. Compared with austenitic stainless steel, its yield strength is significantly improved, and its resistance to intergranular corrosion, stress corrosion, corrosion fatigue and abrasion is significantly improved.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

The idea of duplex stainless steels dates back to the 1920s with the first cast being made at Avesta in Sweden in 1930. However, it is only in the last 30 years that duplex steels have begun to ¡°take off¡± in a significant way. This is mainly due to advances in steelmaking techniques particularly with respect to control of nitrogen content.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

The standard austenitic steels like 304 (1.4301) and ferritic steels like 430 are relatively easy to make and to fabricate. As their names imply, they consist mainly of one phase, austenite or ferrite. Although these types are fine for a wide range of applications, there are some important technical weaknesses in both types.
Type “Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size “OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”

The corrosion resistance comes from the addition of alloying material, mostly the chromium content. The ASTM A790 Pipes are resistant to pitting corrosion and crevice corrosion. The pipes could also be electric fusion welded.

Duplex stainless steels have a microstructure which is 50% ferritic and 50% austenitic. This composition gives them a better strength than either ferritic or austenitic steels. Further details about this topic are given below (see ASTM A790 pipes).

Compared with ferritic stainless steel and austenitic stainless steel, duplex stainless steel pipe has good welding performance. It is neither like the welding heat affected zone of ferritic stainless steel, because of the grain coarsening, the plastic toughness is greatly reduced, nor like austenitic stainless steel, it is more sensitive to welding hot cracks.

The standard austenitic steels like 304 (1.4301) and ferritic steels like 430 are relatively easy to make and to fabricate. As their names imply, they consist mainly of one phase, austenite or ferrite. Although these types are fine for a wide range of applications, there are some important technical weaknesses in both types.

In the annealed condition, S31803 contains approximately 40-50% ferrite. S31803 is often referred to as the workhorse grade and is the most widely used grade in duplex stainless steel pipes. The use of S31803 stainless steel pipe should be limited to temperatures below 600¡ãF.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.64

Duplex 2205 is a nitrogen-enhanced duplex stainless steel designed to solve common corrosion problems encountered with 300 series stainless steels. “Duplex” describes a family of stainless steels that are neither fully austenitic (such as 304 stainless steel) nor purely ferritic (such as 430 stainless steel).
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.65

The structure of 2205 duplex stainless steel consists of a pool of austenite surrounded by a continuous ferrite phase. In the annealed condition, 2205 contains approximately 40-50% ferrite. 2205 is often referred to as the workhorse grade and is the most widely used grade in the duplex stainless steel family.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.66

The advantage of the dual-phase structure is that it combines the advantages of ferritic alloys (resistance to stress corrosion cracking and high strength) with the advantages of austenitic alloys (ease of manufacture and corrosion resistance). The service temperature of 2205 duplex stainless steel should be limited to below 600¡ãF. Prolonged exposure to high temperatures can make 2205 stainless steel brittle.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.67

Duplex 2205 stainless steels are called “duplex” because they have a two-phase microstructure consisting of ferritic and austenitic stainless steel grains. When duplex stainless steel melts, it solidifies from the liquid phase to a fully ferritic structure. As the material cools to room temperature, about half of the ferrite grains transform into austenite grains (“islands”). The result is a microstructure of approximately 50% austenite and 50% ferrite.

Duplex 2205 stainless steel (ferritic and austenitic) is widely used in applications requiring good corrosion resistance and strength. UNS S31803 grade stainless steel was modified several times to form UNS S32205, which was approved in 1996. This grade offers higher corrosion resistance.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.60

S31803 stainless steel is a nitrogen alloy duplex stainless steel containing 22% chromium, 3% molybdenum, and 5-6% nickel. In addition to high strength and excellent impact toughness, it also has high resistance to general corrosion, localized corrosion and stress. Corrosive properties.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.61

The advantage of the dual-phase structure is that it combines the stress corrosion cracking resistance and high strength of ferritic alloys with the ease of manufacture and corrosion resistance of austenitic stainless steel alloys.

“Duplex” describes a family of stainless steels that are neither fully austenitic (like 304 stainless steel) nor pure ferritic (like 430 stainless steel). The structure of the S31803 duplex stainless steel consists of a pool of austenite surrounded by a continuous ferrite phase.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.63

Duplex 2205 is a nitrogen enhanced duplex stainless steel designed to solve common corrosion problems encountered with 300 series stainless steels. “Duplex” describes a family of stainless steels that are neither fully austenitic (such as 304 stainless steel) nor purely ferritic (such as 430 stainless steel).
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.48

The structure of 2205 duplex stainless steel consists of a pool of austenite surrounded by a continuous ferrite phase. In the annealed condition, 2205 contains approximately 40-50% ferrite. 2205 is often referred to as the workhorse grade and is the most widely used grade in the duplex stainless steel family.
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.49

The advantage of the dual-phase structure is that it combines the advantages of ferritic alloys (resistance to stress corrosion cracking and high strength) with the advantages of austenitic alloys (ease of manufacture and corrosion resistance).
Type Seamless Pipe
Seamless Tube
Welded Pipe
Welded Tube
SAW LSAW ERW EFW
Beveled End, Plain End”
Size OD: 1/2″” ~48″”
Thickness: SCH5~SCHXXS
Length :As per your requirement.”
Manufacturing technique Hot rolling /Hot work ,Cold rolling
Producing Standard ASME B36.10 ASME B36.50