Assembly of steel piston crown with aluminium piston skirt - uses connecting screwring with opposite hand threads

摘要

A piston assembly for a combustion engine has a cast iron or steel piston crown (2). The piston skirt (1) which includes the gudgeon pin bearing hole, is made from aluminum alloy. The two components are joined together by a screw ring (3) which has internal and external threads of opposite hand. After assembly of the piston, a dowel pin (4) prevents the components from unscrewing. Piston ring groove(s) is provided in the piston crown.