Posted on May 11, 2018

What is a DIN Fitting?

Ally Pulskamp
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Ally Pulskamp

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You may already be familiar with the term "DIN Fittings" but do you know what it actually stands for and what DIN fittings are commonly used for? 

DIN stands for "Deutsches Institut für Normung", which means "German institute for Standardization".  DIN 2353 tube fittings are most commonly used in industrial, oil & gas and construction equipment in hydraulic and pneumatic applications. Metric O.D. sizes range from 4mm to 42mm, and the most common industrial applications use carbon steel or stainless steel material.

    There are three series of tube port end connections: tube-to-tube, tube-to-female port and tube-to-male thread.

DIN Metric and BSPP (British Standard Parallel Pipe) are the most common thread styles in Europe.  DIN type tube fittings conform to the requirements of ISO 8434-1, DIN 2353, and DIN EN 3850 standards. This ensures the interchangeability with leading brands of fittings.

As with other compression style fittings, DIN 2353 fittings consist of a body, cutting ring (ferrule) and nut.  DIN connections are used in:

  • Tube Fittings
  • Alternating Valves
  • Banjo and Swivel Couplings
  • Check Valves/Non Return Valves

The availability of a variety of body styles and threaded connections allow DIN 2353 fittings to meet many connection challenges. These flareless bite type metric fittings are the most widely used bite type fittings in the world.  As with other compression style fittings, DIN fittings consist of a body, cutting ring (ferrule) and nut.  On assembly, the two cutting edges of the ring (ferrule) bite into the outer surface of the tube ensuring the necessary holding power and seal for high operating pressures and extreme vibration.


For the best results, metric DIN 2353 fittings should be made with high quality materials. Stainless steel 1.4571 (316Ti) is the gold standard, providing exceptional temperature and corrosion resistance.  Stainless steel 316Ti is used in environments with high salt levels, acidity, or near weld seams.  Because of the long service life of this material there is a significant reduction in total cost of ownership, which leads to few parts replacement and lower maintenance costs.

Stainless steel 1.4571 (316Ti) DIN 2353 fittings withstand harsh environments with the presence of:

  • Acid
  • Dirt
  • High heat
  • Physical impacts
  • Salt
  • Vibrations
  • And other corrosive substances in the air

High quality DIN 2353 Metric Bite-Type Fittings and Adapters should be made of 1.4571 (316Ti) V4A materials for most applications that require extreme temperature and corrosion resistance.  However, many applications are well suited for carbon steel which can provide exceptional corrosion protection when applying a specific zinc-nickel plating that far exceeds U.S. and international corrosion resistance standards, including VDMA 24576 class K5.  Zinc-nickel plated fittings should not experience any traces of white or red rust even after 1000 hours of exposure to salt spray testing and provide:

  • Good paintability
  • High abrasion protection
  • High temperature stability
  • Low corrosion when experiencing contact with aluminum or stainless steels

Applications and Industries:

DIN 2353 Metric Bite-Type Fittings are commonly used in industries where tough environmental conditions are prevalent:

  • Construction equipment
  • Drilling platforms
  • Hydropower plants
  • Machine tools
  • Railway technology
  • Recycling equipment
  • Shipbuilding
  • Wind turbines
  • Mobile hydraulic equipment
  • Mining
  • Stationary hydraulic equipment

This blog is an excerpt from our newest whitepaper "Standards, Applications & Styles of DIN 2353 Metric Bite-Type Fittings & Valves".  Click here or below to get your whitepaper!

Click here to get your FREE Whitepaper!

If you're interested in our line of DIN Fittings, click here to download our catalog.

You can also view our product collection on our website by clicking here, or check out our DIN Cap & Plug Kits by clicking here. 


Some additional information in one line


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