FTDFDN65 Fil-Tec Duplex Filter with flange connection DN 32-80 available with heating

Application areas

The FTDF. duplex filter can be used in pressure and suction modes and is versatile for coarse and fine filtration. It is characterized by continuous filter operation during the cleaning phase. The filter is compatible with the FTSF series. The filter combines the so-called housing sizes (GR) with the various nominal widths (DN) of the flange connection. FTDFDN has a bolt and nut lock and can also additionally be delivered with filter cover safety device and differential pressure indicator.

Brief description and function

The duplex filter, cast as a component, comprises two identical single filters, connected via a cock switching device to a filter side or can be operated in parallel. Medium to be filtered enters the filter from the top or the bottom flange ( depending on type of element : multimantle, star,- or candle sieve insert from bottom, Basket-element from top) and flows through the insert inside or outside in/ out. Dirt thus remains in the filter element, basket type or is collected on the surface of filterelement ( Multimantle,-Star,- and candle-sieve-element ).

Safety instructions

Generally, use of filter with switching valve must be checked for hazardous media (leakage rate permitted by the design). FTDF filters are not suitable for the filtration of gases. Check the filter for intended operation prior to usage. Conformity assessment as per PED EN 97/23 EC must be done for changes in operating conditions or the media (kindly contact us for the same or run a risk analysis with conformity assessment).

Technical Characteristics

  • Filter housing of ductile iron; internally nickel lined for water application
  • Change-over valve of cast iron; water filters rubber-lined
  • Optionally star-pleated, candle,- or basket filter element, star-pleated element also available as disposable filter element
  • Filter fineness: 10 microns to 5 mm ( absolute Meshsize)
  • Operating pressure ductile iron up to 25 bars

Optional Acessories

Differential pressure indicator type 4.36 (fig.1) can be supplied fitted at factory. The filter elements can be fitted with magnetic bars. Heating available. Cover safety device (fig.2)


  • Switch change-over valve to clean filter chamber
  • Release pressure in the contaminated filter chamber by means of venting screw
  • Lift the cover of the contaminated filter chamber
  • Remove filter element
  • Soak filter element in cleaning fluid, e.g. Fil-Tec FT 31, and clean with compressed air For details see operating instructions manual ”maintenance and servicing”.
  • Always drain filter chamber and clean it ( in case of multimantle,- pleated and candle inserts, the chamber is dirtside.