The duplex filters have been designed with the goal of a compact design without welds, and with a reduced weight and dimensions.

The filters are built in one piece, in which are installed all main components:

  • Switch valve (Which allows to have always one operating filter, in order to perform maintenance activities and change the cartridges without stopping the system)
  • Balancing and drain valves
  • Cartridges housings.


The duplex filters are designed according to ASME VIII div.1 code last edition, and according to the most important international rules (PED, GOST, NR13, GB150; DPP)  to satisfy the requirements of iron and steel, chemicals, petrochemicals and water treatment plants.

They are available in different versions:

  • DB Progetti standard, completely made of stainless steel 316L
  • Made in carbon steel
  • Made in special materials on request