Pipeline brazed joint structure and brazing leakage

By designing a new type of refrigeration pipe brazed joint, uniform gap brazed joint, to solve the problem of high leakage rate caused by uneven gap of brazed joint. The uniform gap brazed joint consisted of a brazing section and a positioning section, and the brazed seam structure was distributed in a stepped structure. During the brazing process, brazing filler metal flowed into the brazing section of uniform gap by capillary action to play the role of connection. The positioning section controlled the fit gap to ensure that the axis of the intubation tube and the sleeve overlap and play a positioning role, thereby preventing the quality problem of brazing caused by the skew of the insertion tube. By X-ray inspection and cross section morphology, the quality of brazed joints could be accurately judged. A comparative experiment on the uniform gap brazed joints and the existing brazed joints showed that the former had almost no gap unevenness, while 80 \% of the samples in the latter had uneven gaps, and the brazing quality of the former was greatly superior than that of the latter. Uniform gap brazed joint was an effective brazed joint structure that could prevent the leaking of brazed joint.