| 摘要 |
PURPOSE:To stick brazing filler metal uniformly to two pieces of pipe materials in the stage of press-fitting two pieces of the pipe materials having different heat capacities and brazing the same, by heating the fitting parts thereof electrically to temp. lower than the melting temp. of the brazing filler metals then again conducting electricity thereto after a specified cooling period, thereby heating the two pipe materials to the melting temp. of the brazing filler metals approximately simultaneously. CONSTITUTION:After brazing filler metals are disposed in the fitting parts of two pieces of the above-described pipe materials, the fitting parts are subjected to the 1st electrical heating to the extent that said parts do not attain the melting temp. of the brazing filler metals. At the point of the time when the smaller diameter pipe cools down to the temp. lower than that of the larger diameter pipe upon lapse of a specified cooling period, again the fitting parts are subjected to the 2nd electrical heating. Both pipe materials are heated approximately simultaneously up to the melting temp. of the brazing filler metals. As a result, the brazing filler metals are stuck uniformly in the fitting parts of both pipe materials. |
