MULTILAYER PIPE

To provide a multilayer pipe which can suppress occurrence of drip of a burning material caused by heat deformation in combustion, and accordingly can enhance fire resistance.SOLUTION: A multilayer pipe includes an inner layer, an outer layer and an intermediate layer, in which the inner layer and the outer layer each contains a vinyl chloride-based resin and an inorganic filler, the intermediate layer contains a vinyl chloride-based resin and thermally expandable graphite, a content of the inorganic filler contained in the inner layer is 15 pts.wt. or more and 40 wt.% or less with respect to 100 pts.wt. of the vinyl chloride-based resin contained in the inner layer, a content of the inorganic filler contained in the outer layer is 15 pts.wt. or more and 40 pts.wt. or less with respect to 100 pts.wt. of the vinyl chloride-based resin contained in the outer layer, and a content of the thermally expandable graphite contained in the intermediate layer is 1 pts.wt. or more and 15 pts.wt. or less with respect to 100 pts.wt. of the vinyl chloride-based resin contained in the intermediate layer.SELECTED DRAWING: Figure 1 【課題】燃焼時の熱変形によって生じる燃焼物のドリップの発生を抑えることができ、従って、耐火性を高めることができる多層管を提供する。【解決手段】本発明に係る多層管は、内層と、外層と、中間層とを備え、前記内層及び前記外層がそれぞれ、塩化ビニル系樹脂と、無機充填剤とを含み、前記中間層が、塩化ビニル系樹脂と、熱膨張性黒鉛とを含み、前記内層に含まれる前記塩化ビニル系樹脂１００重量部に対して、前記内層に含まれる前記無機充填剤の含有量が１５重量部以上４０重量部以下であり、前記外層に含まれる前記塩化ビニル系樹脂１００重量部に対して、前記外層に含まれる前記無機充填剤の含有量が１５重量部以上４０重量部以下であり、前記中間層に含まれる前記塩化ビニル系樹脂１００重量部に対して、前記中間層に含まれる前記熱膨張性黒鉛の含有量が１重量部以上１５重量部以下である。【選択図】図１