Structure of a Plate Heat Exchanger

A copper-brazed plate heat exchanger consists of several precisely stamped stainless steel plates that are permanently brazed with copper in a vacuum furnace. The structure is essentially as follows:

1. Connections: The connections of a copper-brazed plate heat exchanger form the interface between the heat exchanger and the connected piping system. They are designed to reliably guide both media into the designated flow channels and ensure even distribution across the entire plate pack. In addition, our connection areas are mechanically very robust, as they must withstand the highest pressure and stress forces. At the same time, the precise brazed joint ensures that there is no mixing of the media.


2. Top Plate: The top plates of a copper-brazed plate heat exchanger form the outer closure of the plate pack and play a central role in stability and safety. They are made of solid stainless steel and are firmly brazed to the rest of the plate stack. Thus, they serve not only as a mechanical boundary but also as load-bearing elements that can withstand high operating pressures and temperature fluctuations over the long term. In addition to their stability function, the top plates protect the internal heat exchanger plates from external damage, significantly contributing to the system's longevity. Overall, they represent the interface between functionality, durability, and protection of the entire heat exchanger.


3. Plate Pack:
   • Plates: The plates of the plate heat exchanger are made of corrosion-resistant 304 stainless steel and are stamped with a special chevron or herringbone pattern. This structure increases the surface area, creates flow turbulence, and thus ensures a particularly high heat transfer coefficient.
   • Channels: The staggered stacking of the plates creates alternating flow channels for the two media. These are designed to allow uniform flow without dead zones. At no point are the two media in direct contact; they are completely separated by the stainless steel plates.
   • Copper Brazing: Copper is used as the brazing material between the plates. It permanently joins the plates in a vacuum furnace, reliably seals the channels, and makes additional gaskets unnecessary. At the same time, the copper brazing ensures high pressure and temperature resistance for the entire heat exchanger.


4. End Plate: The end plate essentially serves a similar function as the top plates, as it also forms the outer closure of the plate pack and contributes significantly to mechanical stability. It is also made of solid stainless steel, firmly brazed to the plate stack, and protects the internal heat exchanger plates from external influences.

Functioning of a Plate Heat Exchanger

Brazed plate heat exchangers consist of a series of thin stainless steel plates stamped with a special chevron or herringbone pattern. This structure not only provides stability but also enhances heat transfer by creating turbulence in the fluid. All plates have the same shape but are alternately rotated 180 degrees during stacking. This arrangement creates defined flow channels for both media as well as numerous contact points between the plates. During manufacturing, the plates are joined with copper brazing in a high-vacuum furnace. At the contact points, a robust, permanently sealed connection is formed that withstands high pressure and temperature loads. The result is a compact, low-maintenance heat exchanger without gaskets, which can be used reliably in many applications.

Flow Guidance Inside

In operation, the hot medium, for example, flows into the heat exchanger from the right connection side and passes through every second channel until it exits at the opposite outlet. At the same time, the cold medium enters from the left side, distributes itself across the channels in between, and leaves the heat exchanger through the left outlet. The two media never come into direct contact; they are completely separated by the stainless steel plates. Nevertheless, intensive heat transfer occurs, as the thin plates provide excellent thermal conductivity.

Counterflow Principle for Maximum Efficiency

For particularly high performance, it is recommended to connect the heat exchanger according to the so-called counterflow principle. In this arrangement, the two media flow past each other in opposite directions. This setup maintains the largest possible temperature difference across the entire transfer surface, significantly increasing the efficiency of the heat exchanger. In comparison, in the parallel-flow principle, where the media flow in the same direction, the temperature difference decreases much more quickly. This results in lower heat transfer and thus a reduced efficiency. Numerous technical diagrams and practical examples demonstrate that counterflow operation is the most efficient solution in almost all applications.