| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent inward deformation of an annular body by an external hydraulic pressure, in a cut-off device using the annular body. <P>SOLUTION: The cut-off device has the annular body that is arranged on the inner surface of a pipe body for water cut-off purpose and is made of an annular body, and a fixing plate for fixing the annular body to the inner surface of the pipe body by pressurizing it from the inside to the outside. For preventing inward deformation of the annular body by operation of the external hydraulic pressure, a wall thickness section 13 is formed in part of the annular body 12 and is covered with an external hydraulic resistance board 22, and the external hydraulic resistance board 22 is fixed together with the annular body 12 to the inner surface of the pipe bodies 11 and 11' by pressurizing force by diameter extension of the fixing plate 14. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
