Pillow plates

Heat transfer solutions on a plate?

A detailed look at welding of a thermoplate

At the heat of our technology is the thermoplate also called pillow plate or embossed plate due to the shape of plates after expansion. The thermoplate is a fully welded heat exchange plate.

Material selection is of course key when selecting the right design for a heat exchange duty.

But another key factor and sometimes more important factor is the welding of the thermoplates, a thermoplate can have several hundred spot welds. Each a potential risk for corrosion or fouling if not handle with care.

We at ATHCO-Engineering use resistance welding to produce the spot pattern and the seam welding for the thermoplates.

The resistance welding has a few key benefits compared to other welding techniques

  • No add material to weld
    1. Limited pollution of the metal sheets.
    2. The corrosion and strength of the materials are maintained
  • No visible welding seems
    1. Hence no nucleated spots for fouling, corrosion and freezing
    2. No crevice – highly susceptible for corrosion
  • Only a low heat input at the welding spot
    1. The strength and corrosion resistance of the heat affected zone is nearly that of the parent material
  • No space behind the welding
    1. No risk of corrosion in between the weld metal sheets

This is of course only true when the resistance welding is conducted correctly. We at ATHCO-Engineering have more than 40 years of experience with the resistance welding for thin materials.


Food industry

  • Exhaust recuperators
  • Water chillers (Falling Film)

Chemical industry

  • Top and bottom condensers
  • Vaporizers
  • Heat exchangers

Other industries

  • Condensers
  • Flue gas coolers/condensers
  • Oil coolers
  • Heating –/cooling shells for tanks


  • Very easy to clean (high sanitary standard)
  • Efficient heat transfer because of large surface area to volume ratio

Contact ATHCO Engineering
regarding this solution