| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide "working device and method in piping" characterized in that the running drive force in piping is very large. <P>SOLUTION: The working device in piping is equipped with an annular pressure boundary seal of which the free end part comes into contact with the inner wall of the piping and the pressure boundary seal divides the internal space of the piping into two spaces, that is, a space A and a space B using the pressure boundary seal as a boundary. One end part approaching the pressure boundary seal of the space A is allowed to communicate with a suction pump through a hose and also allowed to communicate with the space B through a vacuum breaking valve mechanism for adjusting the negative pressure in the space A while the other end part separated from the pressure boundary seal of the space A is closed and the hose is arranged in the space B. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
