Frequently Asked Questions

- Here are some of the most frequently asked questions

FAQ - Got a question? Get your answer

INDURA quesitons

  • Norms
    • What is EN 1092-1?
    • What is ASME?
    • What is DIN?
    • What is JIS B2220
  • What is Duplex?


When it comes to fittings and flanges, one of the most crucial terms to understand is the norm. Different norms are applicable to fittings and flanges, which dictate their design and manufacture. The most commonly used norms in the industry include EN 1092-1, ASME, and DIN. 

It's important to understand these norms and their applications when purchasing fittings and flanges, as they dictate the design, quality, and performance of the components. Failing to adhere to the relevant norms can result in faulty or substandard components that could cause operational issues or even pose a safety risk.

What is EN 1092-1?

Answer: EN 1092-1 is a European standard that specifies the requirements for circular flanges for pipes, valves, and fittings. The standard covers the design, manufacture, and testing of flanges, including dimensions, materials, and performance criteria.

What is ASME?

Answer: ASME (American Society of Mechanical Engineers) is an American standard for fittings and flanges, primarily used in the oil and gas industry. The ASME B16.5 standard covers the specifications for pipe flanges, while the ASME B16.9 standard covers fittings.

What is DIN?

Answer: DIN (Deutsches Institut für Normung) is the German equivalent of ASME and covers a range of standards for flanges, fittings, and other industrial components. The most commonly used DIN standard for flanges is the DIN 2633, which covers the specifications for welding neck flanges.

What is JIS B2220

Answer: JIS stands for Japanese Industrial Standard and is published by the Japanese Standards Association (JSA), which is equivalent to the American standard ANSI/ASME or European standard EN 1092-1. This is just another option for metric measurement. Carbon steel JIS flanges are typically used in exported pressure equipment and pipes assembled from Japan.

What is Duplex?

Duplex stainless steel is famous for its excellent combination of good mechanical properties in high corrosion resistance. It is widely used in industrial fields, such as the production of seawater heat exchangers and chemical containers for use in high-concentration chloride environments. 

It also permits the use of thinner sections and helps in weight reduction. The main difference between austenitic stainless steel is that the duplex steel has a higher chromium content, higher molybdenum, and lower nickel and nitrogen level. Duplex is composed of grains of two types of stainless-steel material, austenitic and ferritic. 

Applications and uses of Duplex Stainless steel

  • Chemical processing, transport and storage – pressure vessels, tanks, piping, and heat exchangers
  • Oil and gas exploration and processing equipment – piping, tubing, and heat exchangers
  • Marine and other high chloride environments
  • Pulp and paper industry – digesters, bleaching equipment, and stock-handling systems
  • Cargo tanks for ships and trucks
  • Food processing equipment
  • Biofuels plants

Why use duplex stainless steel?

Duplex stainless steel has roughly twice the strength compared to austenitic stainless steel and also improved resistance to localized corrosion, particularly pitting, crevice corrosion, and stress corrosion cracking. 


Welding is difficult compared to austenite. Close control of heat input is required in order to avoid the action of undesired intermetallic phases.

Varieties of Stainless Duplex

Stainless Duplex comes in a variety of types, at Indura we only stock "duplex - 1.4462" as of now. 

  • Lean Duplex - 1.4362", which is a cheaper and weaker version of duplex.
  • Super Duplex - 1.4410
  • Hyper Duplex - Sandvik SAF2707 which is even more expensive, but can survive the most corrosive environments.