| 摘要 |
PROBLEM TO BE SOLVED: To simplify a joint welding operation and ensure that the joint strength is constantly high and further, the finish appearance is presentable by enveloping an energized heat generating wire, in such a state that the wire is almost symmetrical to the right and the left, in a linear material of a polyolefin resin which is symmetrical to the right and the left in the vertical direction as viewed in a cross-section. SOLUTION: The welding rod 1 comprises a linear material 3 of a polyolefin resin which is symmetrical to the right and the left in the vertical direction as viewed in a cross-section and an energized heat generating wire enveloped in the linear material 3 in such a manner that the wire 2 is almost symmetrical to the right and the left in the cross-section. For the energized heat generating wire 2 enveloped in the linear material 3, an alloy having a high electrical resistance value is used. Thus it is possible to obtain a high welding strength and ensure that the finish appearance is very presentable. In addition, the melting operation with an extremely high efficiency can be performed and the joint can be made to appear highly presentable from a viewpoint of design. |
