Danfoss SONDEX®

Heat Exchangers

SONDEX® semi-welded
plate heat exchangers

Our SONDEX® semi-welded plate heat exchangers are the prime choice for challenging applications that involve aggressive media or high pressure. The semi-welded plate heat exchangers are very versatile which means that they can easily be configured for use in different industries and applications that involve challenging media, such as chemical processing.

We customize each heat exchanger according to your specifications and offer durable solutions designed to withstand extreme conditions and minimize the risks of operation.

You can safely operate with hazardous or aggressive media, high pressure, or extreme temperatures that are unsuitable for regular fully gasketed heat exchangers. We design to give you peace of mind.


Semi-welded plate heat exchanger for industrial refrigeration ammonia applications


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



How does a SONDEX® plate heat exchanger work?


What kind of heat exchanger is right for me?

The choice of heat exchanger depends on many factors. Our skilled sales engineers design the heat exchanger with the appropriate dimensions and correct specifications based on your input and requirements, to ensure that you receive a quality solution that performs optimally.

Which certificates are available for the heat exchangers?

Our heat exchangers are approved and certified according to industry standards and requirements. For specific details, please reach out to your local SONDEX® brand sales representative.

Where can I get a price list?

Please contact your local SONDEX® brand sales responsible.

How can I get a quotation?

Please contact your local SONDEX® brand sales office. For the most accurate quotation, please prepare the following data:

• Duty,
• Type of media,
• Pressure drop,
• Flow rate,
• Working pressure,
• Thermodynamic properties, Temperature,
• Working temperature.


What would you like to know more about? We offer a wide range of informative content relating to our products. You can find general information about our products in brochures, technical specifications on data sheets, and various instructions in operating and maintenance guides.

Want to know more?

Please get in touch with your local contact person for more information and learn how Danfoss can help improve your business. Additionally, please feel free to send us a mail.

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