Manufacturing method of a piston for an internal combustion engine

摘要

A manufacturing method of a piston in used for an internal combustion engine. The method comprises a step of reinforcing a circumference of a top ring groove by an inorganic fiber assembly, a step of forming an oil cooking gallery by a soluble core, a step of fixing the soluble core by projections formed in a strut preventing a thermal expansion of the piston, a step of setting the soluble core in a position supported by a punch mold, and step of setting the inorganic fiber assembly in an annular groove of a lower mold.