| 摘要 |
PURPOSE:To prevent cracking in the joint weld zone between pipings by covering the outside surface of the weld zone with a backing strap, and welding both ends of the strap to the pipings. CONSTITUTION:The outside surface of a joint weld zone 2 between pipings 1 is covered by a backing strap of a bisected sleeve 4, etc. and both ends thereof are respectively welded to the pipings 1. The sleeve material having the coefft. of linear expansion smaller than the coefft. of the piping is used if the fluid flowing in the piping 1 is of a high temp. and the material having the larger coefft. of linear expansion is used if the liquid is of a low temp. The stress on the contraction side is thus exerted on the piping 1 body side owing to a difference in the coefft. of linear expansion between the piping 1 body and the strap 4, by which the generation of a crack 3 in the weld zone 2 is prevented. |
