| 摘要 |
PURPOSE:To prevent the deterioration in strength due to mutual peeling by making the linear expansion coefficients of a metal pipe and a reinforcing material almost equal when the reinforcing material impregnated with thermosetting binder is wound on the metal pipe and the same is thermoset in a heating oven to manufacture a reinforced pipe. CONSTITUTION:An embossing process on a recessed section having the depth of less than the wall thickness of pipe on the outer or inner peripheral face of a metal pipe in the peripheral direction is added preliminary to the manufacturing process of a reinforced pipe consisting of a process of winding a reinforcing material impregnated with a thermosetting binder on the outer peripheral face of the pipe and a process of heating the outer peripheral face of the metal pipe and thermosetting the reinforcing material. Mechanical potential stress to shrink all the time in the axial direction is applied to the formed recessed section, and the reinforcing material is not peeled off, as the shrinkage in the axial direction is not generated on the metal pipe itself when the reinforcing material is thermoset by inner-oven heating, and then released and cooled naturally. |
