| 摘要 |
A multi-layered synthetic resin tube having a foam resin material and an apparatus for manufacturing the same are provided to lengthen a lifespan of a pipe by thickening an inner wall in comparison with an outer wall. A multi-layered synthetic resin tube having a foam resin material includes an inner wall(71), an outer wall(72), a plurality of through-holes(73), and a foam resin material(76). The outer wall is spaced apart from the inner wall by a predetermined distance in a concentric manner. A plurality of through-holes connect the inner wall to the outer wall and are formed of a plurality of spokes disposed at predetermined intervals. The foam resin material is provided in at least one through-hole.
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