Duplex Stainless Steel Metal Products

Arc Alloys Limited offers a large variety of products in Duplex Stainless Steel alloys such as tubing, seamless- and welded pipe, butt weld fittings, flanges, pressure fittings and fasteners.

What is Duplex Stainless Steel?

We offer a wide range of metal products, and a range of which come in Duplex Steel. Duplex steel is a mixture of two microstructures, of equal proportions, called ferrite and austenite. Duplex stainless steel is graded by their performance at resisting corrosion based on their alloy content.


  • High strength
  • A cost-effective alternative to austenitic stainless steel 316L.
  • High resistance to pitting, crevice corrosion resistance
  • High resistance to stress corrosion cracking, corrosion fatigue and erosion,
  • Good sulfide stress corrosion resistance,
  • Low thermal expansion and higher heat conductivity than austenitic steels,
  • Good workability and weldability,
  • High energy absorption.


  • Heat exchangers, tubes and pipes for production and handling of gas and oil,
  • Heat exchangers and pipes in desalination plants,
  • Pressure vessels, pipes, tanks and heat exchangers for processing and transport of various chemicals,
  • Pressure vessels, tanks and pipes in process industries handling solutions containing chlorides,
  • Rotors, fans, shafts and press rolls where the high corrosion fatigue strength can be utilized,
  • Cargo tanks, piping and welding consumables for chemical tankers.
  • Material : Duplex
  • Common names: DSS,31803,32205,SAF2205®,F51,F60
  • Uns( unified Numbering system ) : UNS S31803, UNS S32205.
  • Werkstoff : 1.4462,

Arc Alloys ltd supplies Super Duplex in the following Product Forms:

  • Seamless pipe to ASTM A790 and ASME SA790
  • Welded pipe to ASTM A928 and ASME SA928
  • Flanges to ASTM A182 and ASME SA182
  • Fittings to ASTM A815 and ASME SA815
  • Bar to ASTM A479 and ASME SA479
  • Plate to ASTM A240 and ASME SA240
  • We also supply special machined turned parts and bolting in Duplex made from several of the above product forms.

Call Arc Alloys Today on  01384 79695 

What are the different grades of duplex?

Duplex steel comes in 3 main gradations, these are based on their corrosion resistance. The duplex stainless steel grades used are lean duplex, standard duplex and super duplex. The difference in each category is the amount of chromium present in each duplex. The higher the ratio of chromium used in stainless duplex steel, the more resistant to erosion duplex steel is. The major difference between duplex and super duplex stainless steel is standard duplex uses up to 23% chromium and super duplex uses 24% and up. While it may seem, the obvious choice is to go for the highest level of chromium, super duplex is not always the most cost effective and it really depends on the application of the duplex steel.

What are the advantages of using Duplex Stainless Steel?

Duplex stainless steel has many advantages; in general terms it is a popular choice for many applications. Many duplex stainless-steel grades can be two times stronger than other stainless-steel gradations. Due to this they have a higher toughness and ductility, meaning it can be stretched out into thin wires effectively. As mentioned previously, depending on the duplex stainless steel grade, duplex steel has a high corrosion resistance. All this combined with duplex steel being more cost effective than other grades of metal, due to the lower levels of more expensive minerals such as nickel. Duplex steel pricing is also usually more consistent than other steel grades which makes it easier to do cost estimates.

What is Duplex Stainless Steel used for?

Due to duplex stainless steels durability, it is well suited to heavy duty applications. Offshore operations such as oil rigs and drilling are a very good use for duplex steel. Duplex 2507 and 2205 duplex stainless steel are commonly used duplex stainless steels in these situations as sea water is much more corrosive than fresh water. If the situation requires a higher level of corrosive resistance, then the super duplex 2507 is a better choice. The construction industry also uses duplex steel in many machines as they offer great durability and strength at a cost-efficient price. Not only that, the super duplex 2507 can be used for structural components when erecting large structures.

What do Arc Alloys do in terms of Duplex?

Arc Alloys offer a wide range of top-quality duplex steel products. Whether it be pipes, pipe fittings and flanges, or welding consumables, we have a large array of products right for you. We also offer superior machining capabilities to get the right fit on nuts and bolts!

Why should you buy your Duplex Stainless Steel from Arc Alloys?

Arc Alloys aren’t just about top-quality products, we always make sure our customers are happy. With over 30 years of experience in the fabrication and welding industry, we know what we are talking about. To prove this, we offer 24/7 technical advice. It is difficult to find time for advice during the traditional work hours, so we made it easier for you to contact us! So don’t delay and reach out to us for one of our many robust duplex steel products!

Contact us for more information

Telephone: 01384 79695 / 01384 77211

Out of hours: 07973381528

Fax: 01384 79699

E-mail: sales@arcalloys.com