| 摘要 |
PURPOSE:To provide a composite pipe wherein a gap is not present between an outer pipe and an inner pipe even when an adhesive layer is foamed and cured, and the corrosion of the outer pipe is not generated and a pipeline is not closed even when hot water is allowed to flow, by using a synthetic resin pipe, which has intermittent ridges provided on the outer surface thereof in the lateral direction thereof so as to be arranged at an almost equal interval in the circumferential direction thereof, as the inner pipe. CONSTITUTION:For example, each of intermittent ridges has a small triangular cross-sectional area and is protruded from the outer surface of an inner pipe and the height thereof is pref. made almost equal to the gap between the inner pipe and an outer pipe formed when both pipes are arranged coaxially and the length thereof in the axial direction of the pipes is 1.0-10mm, pref., 1.0-5mm and the interval between the ridges in the axial direction is 10-100mm, pref., 30-70mm. These intermittent ridges are provided to the outer surface of the inner pipe at an almost equal interval of 10-30mm in the peripheral direction. |
