Apparatus and method for forming an antipollution device housing

A method of forming a workpiece with an outer profile at least partially defined by an outer surface thereof at an initial position into a housing with a non-round design outer profile at least partially defined by the outer surface at a design position reduced from the initial position thereof, the method comprising:

• (a) providing a plurality of jaw segments including a first group of jaw segments and a second group of jaw segments, each of said plurality of jaw segments having an internal surface for engaging the outer surface;
• each of said plurality of jaw segments being movable between a first condition, in which an opening is defined in which the workpiece is receivable, and a second condition, in which the internal surfaces of the plurality of jaw segments substantially define the design outer profile of the housing, each said internal surface defining a respective portion of the design outer profile;
• the first group of jaw segments associated with a preselected first end point defined by a first radius centered on the preselected first end point and substantially coincident with the portions of the design outer profile substantially defined by said internal surfaces of the first group of jaw segments;
• the second group of jaw segments associated with a preselected second end point defined by a second radius centered on the preselected second end point and substantially coincident with the portions of the design outer profile substantially defined by said internal surfaces of the second group of jaw segments, wherein the preselected first end point is spaced away from the preselected second end point;
• the first group of jaw segments each being movable along a predetermined path therefor, when moved from the first condition to the second condition, toward the preselected first end point, and when moved from the second condition to the first condition, away from the preselected first end point therefor;
• (b) moving the plurality of jaw segments to the first condition;
• (c) inserting the workpiece in the opening after said step (b);
• (d) moving the first group of jaw segments from the first condition to the second condition by moving the first group of jaw segments toward the preselected first end point;
• and
• (e) moving the second group of jaw segments from the first condition to the second condition by moving the second group of jaw segments toward the preselected second end point.