| 摘要 |
<p>PROBLEM TO BE SOLVED: To facilitate piping work by arranging the pipes by the same route by respective set boom body groups. SOLUTION: In this five-stage telescopic boom is so constituted that mutually adjacent first to third boom bodies 1 to 3 and the third to fifth boom bodies 3 to 5 are made into one set, the intermediate boom bodies 2, 4 is contracted by contracting force of expansion cylinders 6, 7, the tip boom bodies 3, 5 may be contracted by a rope-type contracting mechanism, and pipes 10 are arranged from the base end side to the tip end side. In this case, movable parts 10a of the pipe in respective set boom body groups is laid by the same route as a contracting rope 8 of the rope-type contracting mechanism, fixing parts 10b are provided outside the base end boom bodies 1, 3, and the pipes are arranged by the same route by respective set boom body groups.</p> |
