Vacuum brazing process of EGR stainless steel cooler

Structural materials of each part of EGR: the materials of the two connecting flanges are ZG0Cr18Ni9 stainless steel, the water pipe joints and shell of the two joints are 304 stainless steel, and the connecting plates, cooling pipes and spiral fins are all 316 stainless steel.

The vacuum brazing process of EGR cooler is as follows: stamping – cleaning – finned clamping of core component – machine coating paste blocking flux – drying – shell assembly – core swelling in component cooling pipe – assembling flange – argon arc welding water pipe – integral vacuum brazing – pressure test and inspection – compact, the important link is vacuum brazing.

The process curves of vacuum brazing two different solders are shown in the figure below :