Abstract: A pipe for gases and liquids made of heat-resistant plastic comprises a cylindrical body with a perimetric attachment flange having bores for attachment screws and is reinforced by an integrally molded reinforcement ring which is disposed concentrically around an end of the pipe and which is provided with side extensions that concentrically surround the bores of the flange and that have a height that is the same as the thickness of the flange in proximity to the bores. The side extensions may be shaped to provide integral washers at the bottom (attaching face) of the flange.