| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for connecting tapered metal pipes in upper and lower tiers simply with a bolt and nut, thus mitigating labor for installation and absorbing displacement in a vertical direction especially of the tapered metal pipe in the upper tier.SOLUTION: When joining tapered metal pipes 10, 20 of which a diameter gradually widens in a downward direction, the tapered metal pipe 10 in an upper tier is inserted into the tapered metal pipe 20 in a lower tier from above, so as to hold an inner surface 10a of the tapered metal pipe 10 in the upper tier and an outer surface 20a of the tapered metal pipe 20 in the lower tier in a surface-contacting state. A bolt 12 is inserted through a long hole 11 extending vertically and formed in a surface-contacting area of the tapered metal pipe 10, and the bolt 12 is screwed into any one of a plurality of circular holes 25 formed in a vertical direction in a surface-contacting area of the tapered metal pipe 20, such that a circumferential surface of the circular hole 25 is plastically deformed into a female screw form, for screwing the bolt 12 thereinto.SELECTED DRAWING: Figure 7 |
