| 摘要 |
A method of producing an injection-moulded plastics article (10) having a hollow interior, such as a pipe section, comprises the steps of forming a mould cavity having outer dye parts (11, 12) and an inner mandrill (13) to define an annular mould cavity, introducing plastics material into the mould cavity (14) and delivering a pressurised fluid to the interface between the mandrill and the inner surface of the moulded article through passages (37) in the mandrill (13) opening to the surface thereof, and withdrawing the mandrill (13) while maintaining the outer dye parts (11, 12) in a closed condition. Apparatus for producing such hollow moulded article, the hollow moulded article itself, and a method of lining an aged, broken or damaged pre-existing pipeline are also described. |
