Heat ExchangersDanfossSONDEX®SONDEX semi-welded plate heat exchanger


SONDEX semi-welded plate heat exchanger

The SONDEX semi-welded plate heat exchanger is the best choice for challenging applications involving high pressures or aggressive media. The SONDEX semi-welded plate heat exchangers are highly versatile, meaning they can be easily configured for use in a variety of industries and applications where difficult media are used, such as chemical processing.

We will engineer each heat exchanger based on your specifications and provide durable solutions that can minimize the risks of use and withstand extreme conditions.

You can use the equipment safely with hazardous or aggressive media, high pressure or extreme temperatures, such as media that are not suitable for standard gasketed heat exchangers.

Features and benefits

  • High efficiency means that fewer plates are needed for high performance and consequently lowers the hold-up volume. Fewer plates also lowers the cost of each heat exchanger, as an added bonus.
  • Engineered to use smaller amounts of potentially hazardous media, the SONDEX semi-welded range is a safe and responsible choice for demanding duties.
  • Unique gasket system intended for high working pressures and vacuum applications. A closed gasket groove keeps the gasket firmly in place and prevents misalignment of the plate pack during assembly and operation.

Technical specifications

  • Connections from DN65 to DN500 (2½” to 20″)
  • (Frames designed according to FEA and PED 2014/68/EU (EN13445) and ASME sec VIII, Div. 1 construction standards)
  • Plate materials: AISI 304/316, titanium, SMO, Hastelloy*
  • Gasket materials: EPDM-HT, NBR-HT, Viton*
  • Ring gasket materials: EPDM-HT, NBR-HT, Viton, Chloroprene, PTFE*
  • Plate heights up to 3 m (9.8 ft)
  • Flow rates up to 5,000 m3/h (22,014 gpm)
  • Working pressure up to 30 bar (450 psi)
  • Working temperatures from -20 °C to 180 °C (-4 °F to 356 °

*other materials available upon request.


  • HVAC industry
  • Marine/offshore industry
  • Dairy/food/beverage industry
  • Sugar industry
  • Pulp and paper industry
  • Heavy industry
  • Mining industry
  • Petrochemical industry
  • Chemical industry
  • Evaporation and condensing duties
  • High pressure liquid/liquid applications
  • Semi-welded plate heat exchanger for industrial refrigeration ammonia applications