Method for making a composite engine cylinder block with preformed liner

摘要

A method and apparatus for making engine cylinders comprising the steps of punching cylindrical tubes with openings from the inside to the outside and then surrounding the thus formed tubes with a different body of material. In accordance with the method, the punching apparatus includes a mandrel that slidably supports the dies and a backup die that includes a slug ejecting punch which serves the dual function of ejecting the slugs from the backup die and also retracting the punches. In one embodiment of the invention, the port openings are formed smaller than the final configuration and the surrounding material is cast in place and extends into the liner opening for interlocking the surrounding material to the liner.