DIN2353 fittings are the most widely used bite-type fittings in the world, and they don’t require O-rings or other elastomers to make a leak-tight seal.
DIN 2353 tube fittings are used in a wide variety of fluid power applications, especially in factory, oil & gas, and construction equipment. Metric sizes from 4 to 42mm made of carbon steel or stainless steel are most prevalent. DIN (Deutsches Institut für Normung, translated as the German Institute for Standardization) 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 interchangeability among leading brands of fittings.
DIN2353 metric fittings are available in three series of tube port end connections: tube-to-tube, tube-to-female port, and tube-to-male thread. They are also offered in three different pressure series—LL for Extra Light and intended for low-pressure applications, L for Light and used medium-pressure applications, and S for Heavy, used high-pressure applications. They are identified by measuring the thread size, pitch and the tube’s outside diameter (OD).
Although DIN 2353 fittings and adapters made of 1.4571 stainless steel is especially important for applications requiring extreme temperature and corrosion resistance, carbon-steel can be protected from corrosive environments if the fittings use a suitable coating or plating. For example, Brennan offers a proprietary zinc-nickel plating that far exceeds U.S. and international corrosion resistance standards, including VDMA 24576 class K5.
Zinc-nickel plated fittings should not exhibit any traces of white or red rust even after 1,000 hours of exposure to salt spray testing. Carbon steel fittings can be especially vulnerable to galvanic corrosion when they come in contact with aluminum or stainless steels, so it’s important that the plating offer protection under these conditions. The plating should also readily accept paint, powder coating, or other finishes applied by OEMs. The plating should also be hard enough to resist abrasive wear and provide good high-temperature stability.