Method of brazing a plate heat exchanger using screen printed brazing material; a plate heat exchanger manufacturing by such method

摘要

A method for brazing a plate heat exchanger comprising a stack of heat exchanger plates (110,115) is provided with a pressed pattern of ridges (R) and grooves (G) adapted to form contact points between the plates (110, 115) and provide for interplate flow channels for media to exchange heat is provided. The interplate flow channels are in selective fluid communications with port openings (120, 130, 140, 150) provided near corners of the heat exchanger plates (110, 115). The method comprises the following steps:calculating or measuring the exact position of all contact points between the ridges (R) and grooves (G) of the neighboring plates (110, 115);applying brazing material (B) close to, but not at, the contact points;stacking heat exchanger plates (110, 115) provided with brazing material to a stack;placing the stack of heat exchanger plates (110, 115) in a furnace;heating the stack of heat exchanger plates (110, 115) to a temperature sufficient for melting the brazing material (B); andallowing the stack of heat exchanger plates (110, 115) to cool down such that the brazing material (B) solidifies and binds the plates (110, 115) together.