Cooling high-vacuum electrical furnaces with air heat exchangers

The Alfa Laval proposal to use a V-type dry cooler to provide the necessary cooling of two high-vacuum electrical furnaces in its brazing processes at a manufacturing industry in Italy, was quickly accepted.

DATE 2023-11-28

Furnace function is based on electrical resistance. The brazing area is completely covered with a layer of graphite and a water jacket keeps this graphite layer warm. At a predefined temperature, the water is circulated with pumps to remove the heat. See schematic drawing of how the plant works:

 A pump moves a fixed quantity of water from an underground tank through the furnace jackets, while another pump moves water from the same tank through the dry cooler.

One of the key objectives for the Italian customer was to reduce required maintenance as much as possible. In particular, there were important considerations regarding the cooling towers. With Alfa Laval dry coolers the need for maintenance and operating costs are less compared to when using cooling towers, so the choice was easy to make.


Optimized V-type dry cooler design provides large capacity with compact size. It has new fin corrugation combined with smooth tubes. Heat exchanger constructed of aluminium fins and copper tubes with nominal diameter of 1/2". Double connections provide capability for two completely independent heat exchangers.

 Alfa-V ACV dry cooler, capacity range 115 - 1640 kW 

 Alfa-V ANV dry cooler, capacity range 97 to 1682 kW 

Challenge and solution

To reduce required maintenance as much as possible. 


Alfa Laval's dry cooler proposal was chosen because of the following benefits:

  • Less maintenance
  • No water consumption
  • No risk of legionella
  • Easy capacity control