Basic structure of the brazed plate heat exchanger

Basic structure of the brazed plate heat exchanger

Brazed plate heat exchangers consist of a series of stainless steel plates—each stamped into specific corrugated patterns.
These precision-engineered corrugations (e.g., herringbone, dot-type) serve two key purposes:
Boost turbulence: Create intense fluid disturbance in flow channels, break the boundary layer, and significantly improve heat transfer efficiency.
Withstand high pressure: Act as multiple support points to enhance the mechanical strength of the plate stack, enabling it to bear higher pressure.

Working principle of brazed plate heat exchangers

Each pair of adjacent plates forms a flow channel.
Holes are punched at the four corners of each plate. With a specialized design of plates and gaskets (in brazed plate models, gaskets are replaced by brazing filler metal), two fluids (e.g., cold and hot media) flow countercurrently in adjacent channels.
One fluid enters through the top-right hole, flows through odd-numbered channels, and exits via the top-left hole. The other enters from the bottom-left, passes through even-numbered channels, and exits at the bottom-right—enabling highly efficient heat transfer.

The core process of brazed plate heat exchangers

In a vacuum brazing furnace, the plate stack is pressurized and heated above the melting point of the brazing filler (typically copper or nickel-based alloy).
Molten filler uniformly fills all inter-plate contact points via capillary action. Upon cooling, it forms strong alloy welds, bonding the entire stack into a solid, inseparable core.

Main features of brazed plate heat exchangers

High Efficiency & Compact Design: Exceptional heat transfer efficiency with a large heat transfer area in a small volume. Its volumetric heat transfer capacity is several times that of shell-and-tube heat exchangers.
High Pressure Resistance: Integral brazed structure (no rubber gasket limitations) offers far higher pressure tolerance than removable plate heat exchangers—typically handling 30 bar or more.

Robust & Lightweight: One-piece construction ensures excellent shock and mechanical impact resistance, paired with a lightweight design.
Cost-Effective: Simple structure and fewer components deliver cost advantages in mass production.
Versatile Medium Compatibility: Especially models with nickel-based brazing filler—suitable for more corrosive media or applications where copper ions are prohibited.