The Schmidt^® all-welded plate heat exchanger adopts the design of sealing based on the full welding process, with the integrated plate bundle formed through argon arc welding, which eliminates the need for use of gaskets for sealing, thereby effectively solving the problems such as poor sealing and serious leakage of the traditional heat exchangers under complex working conditions like high temperature and corrosive media. Therefore, the product can adapt to various complex working conditions, ensuring stable and safe operation in the heat exchange process.