| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a vacuum seal construction method for a vacuum heat-insulation type double-pipe capable of performing strong vacuum seal to an outer pipe for vacuum heat-insulation, and to provide a vacuum heat-insulation type double-pipe provided with the vacuum heat insulating outer pipe, to which strong vacuum seal is performed. <P>SOLUTION: Inside the outer pipe 2 of the vacuum heat-insulation type double-pipe, which is formed by externally fitting the vacuum heat insulating outer pipe 2 on a fluid carrying inner pipe 1, is evacuated by a vacuum discharge pump through an air discharge opening OUT provided in a pipe wall of the outer pipe 2, and thereafter, vacuum seal is performed to the air discharge opening OUT. Before discharging air for evacuation, brazing filler metal 6 is previously led into an air discharge passage for discharging air of the outer pipe for evacuation, and the brazing filler metal 6 is heated for melting after discharging air for evacuation, and the brazing filler metal is solidified to perform vacuum seal to the air discharge opening OUT used to discharge air for evacuation inside the outer tube 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
