| 摘要 |
PURPOSE:To facilitate setting at the time of clamping even when joints such as an elbow or the like are contained in a piping material to be connected. CONSTITUTION:A plurality of marks MJ, MJ are formed on the outer peripheral surfaces S1, S2 of at least the pipe end parts of piping materials J1, J2 to be connected along the peripheral directions of the piping materials at a predetermined pitch so as to show the positions in the peripheral directions of the outer peripheral surfaces. When the piping materials J1, J2 are clamped by a pair of clamps 1, 2, the pipe end surfaces of the respective piping materials J1, J2 are brought into contact with each other and the piping materials J1, J2 are respectively fixed in such a state that the respective marks MJ are mutually matched to perform the angle indexing of the piping materials. |
