When to use WPHE Welded Plate Heat Exchanger

The typical feature of Plate & Frame Heat Exchanger (PFHE) is opportunity to open and clean both circuits. Weak point is the gasket, that generates limits in terms of working pressure and design temperature, plus not suitable materials for multiscope applications.

Therefore general trend in recent years has been replacing gaskets with welding (TIG or laser) to work with ammonia (semiwelded PHE), in Gas Sweetening (Lean/Rich ammine) and Gas Dehydration (TEG/MEG) with Plate & Shell Heat Exchangers (PSHE).

But in both cases one side only can be cleaned. So in case of dirty fluids selection should be Bloc type Heat Exchanger, with cross flow and access to both circuits.

There are hundreds of Bloc type units installed all over the world, expecially in the Middle East on lethal service in Oil & gas applications.

Limitation was in the past small gap of channels, but recently KAPP introduced HEATEX®HXE Free gap up to 40mm on one channel.

At the end of the day if fluids are not involving particles or very high density Plate & Shell is the right choice, otherwise Bloc type is the proper selection with latest chance to use large free gap.