Method for manufacturing piston for e.g. Otto engine, involves covering passage by ring, and increasing diameter of ring to limited extent, where projection projects to large extent such that ring completely seals passage

摘要

The method involves hollowing a region that comprises a cooling passage and a piston ring groove. The cooling passage is covered by a ring (10) e.g. piston ring and seal ring, and diameter of the ring is increased to a limited extent. A projection (14) is engaged with a recess (16) in an overlapping region (12) in the ring, where the projection axially or radially projects to a large extent such that the ring completely seals the cooling passage. The projections are oriented up to an angle of 90 degree, where thickness of the ring is reduced in the overlapping region. An independent claim is also included for a piston for a combustion engine.