| 摘要 |
PURPOSE:To increase the efficiency of propelling work and increase the durability of fluid pipes by providing a second telescoping mechanism telescoping together with a propelling pipe to a fluid pipe in the propelling pipe in which a first telescoping mechanism telescopable in the pipe axis direction is provided. CONSTITUTION:Following a propelling drive head 5 to propel in the ground, multiple propelling pipes 2, 2a, and 2b to transmit a propelling force to it are connected in series, and fluid pipes 18 are installed internally into them. Also a first telescoping mechanism D telescopable in pipe axis P direction is installed to a part 2a of at least multiple propelling pipes. In addition, a second telescoping mechanism telescoping together with the propelling pipe 2a is provided in the fluid pipes 18... in the propelling pipe 2a in which the first telescoping mechanism D is installed. Thus the propelling pipe 2a can be telescoped smoothly. |
