A height adjustment apparatus that can reduce a load to trim a can body is provided. The height adjustment apparatus 1 is adapted to adjust a height of a can body to a desired height by trimming one of opening ends of the can body. The height adjustment apparatus comprises: mandrels on which the can body is individually mounted and which revolve along a predetermined orbit while rotating; outer blades arranged around the revolution orbit of the mandrels; an inner blade fitted onto each mandrel to trim the opening end of the can body together with the outer blade; and a vertical reciprocator that gradually changes a level of the opening end of the can body with respect to a level at which the outer blade and the inner blade are situated from an upstream side toward a downstream side in a revolution direction of the mandrel.

A method and apparatus for forming aerosol cans for metered dose inhalers.