| 摘要 |
PURPOSE:To form a rustproof film of copper solder on the surface of an iron connecting pipe at the same instant when it is coupled to an iron vessel of refrigerator by means of the copper solder in the stage of coupling said pipe to said vessel by disposing the excess copper solder material in the joint part between the vessel and the connecting pipe and heating the same. CONSTITUTION:Upper, lower covers 4, 3 are put on an iron vessel 1 of a refrigerator, and an iron connecting pipe 5 is inserted into the connecting part of the cover 3. An annular copper solder material 7 is fitted between the vessel 1 and the covers 3, 4, and an annular copper solder material 8 is fitted to the cover 3 side of the pipe 5. These are put in a heating furnace and is heated to 1,050- 1,100 deg.C in a reducing atmosphere to melt the materials 7, 8 and to allow the same to enter the inside of the joint between the covers 3, 4 and the vessel 1 and the spacing between the connecting part 6 of the cover 3 and the pipe 5 by capillarity, thereby soldering these. In this case, the copper solder material in the spacing between the connecting part 6 of the cover 3 and the pipe 5 is used excessively and the excessive molten copper solder flows down onto the surface of the pipe 5, thereby forming a rustproof film 9. |
