Abstract: To support a shell case having a different shape by support mechanisms in a shell lock seaming machine, the support mechanisms are disposed on both the sides of the opening edges of the shell case and a plurality of support members are provided with each of the support mechanisms, the plurality of support members being locked to the inner surface of both the opening edges of the shell case, wherein the plurality of support members can advance and retreat in the axial direction of the shell case as well as at least one of the plurality of support members is movable in a direction perpendicular to the axial center of the shell case.

Abstract: In a silencer shell forming apparatus, a mandrel is divided into an upper segment and a lower segment as well as both the segments are permitted to move in a vertical direction to dispense with a setup job when a different type of a shell is formed. Further, a drive mechanism is provided to cause both the segments to move in a direction where they become nearer to each other and in a direction where they are separated from each other.