Centrifugal molding method for composite pipe having a resin concrete

Abstract

A centrifugal molding method which can smooth the inner surface of the resin concrete layer of a resin concrete pipe or of a composite pipe having a resin concrete layer even without using any special sand conditioning mechanism and which is high in productivity includes producing a composite pipe having a resin concrete layer or producing a resin concrete pipe by moving an arm member of a pipe material feeding device forward and backward axially through a pipe forming outer mold rotating about an axis thereof and by feeding pipe materials from a discharge port formed in a front end of the arm member. The resin concrete layer is formed by feeding resin and aggregate to a mixing portion provided at the front end of the arm member through separate feed routes, mixing the two in the mixing portion and discharging the resulting mixed resin concrete material from the discharge port.