METHOD OF MANUFACTURING A CURVED PIPE USING GAS INJECTION, A CURVED PIPE MANUFACTURED BY THE METHOD, AND A DIE FOR FORMING THE CURVED PIPE

摘要

A method for manufacturing a bent pipe by injecting gas, the bent pipe, and a metallic mold are provided to simply make the bent pipe in any shape by using a gas injection molding method. A method for manufacturing a bent pipe by injecting gas comprises the steps for manufacturing a metallic mold having a bent cavity and a spare unit elongated on both ends longer than a desired bent pipe, and forming the spare unit with a metallic mold gate and a gas injection hole(100); filling the cavity of the metallic mold by injection-molding and inserting gas through the gas injection hole(200); drawing out and hardening a semi-product after finishing a forming work(300); and cutting the elongation unit of both ends formed by the spare unit of the metallic mold(400). The spare unit of both ends of the bent pipe is variably deformed according to a final product in the step for making the metallic mold.