| 摘要 |
The invention relates to a method and an apparatus for manufacturing hollow tubular bodies having a circular, internal cross-sectional shape, from a compressible material. A mixture of plastics material and a filling material, with the plastics material preferably in a molten state, is supplied to a first space defined by an inner core or mandrel (4) and an outer matrix (5), where the mixture is subjected to compression. The compressed material (B) is pressed to a second space (6) between a rotatable core (7) and the matrix (5), where the plastics material solidifies. A part of the rotatable core (7) has an elliptical cross-sectional shape and the core (7) functions to impart a circular internal cross-sectional shape to the hollow tubular body during its manufacture. |
