Method of assembling a two-piece twist lock piston

A method of assembling a piston comprising:

• forming a crown portion generally defining a crown axis and having a skirt connecting portion, the skirt connecting portion defined, at least in part, by a first crown mating portion, a second crown mating portion positioned radially distal from the first crown mating portion, and a crown chamber surface extending between the first crown mating portion and the second crown mating portion;
• wherein the first crown mating portion provides a plurality of radially extending first crown protrusions;
• wherein the second crown mating portion provides a plurality of radially extending second crown protrusions;
• forming a skirt portion having a crown connecting portion, the crown connecting portion defined, at least in part, by a first skirt mating portion, a second skirt mating portion positioned radially distal from the first skirt mating portion, and a skirt chamber surface extending between the first skirt mating portion and the second skirt mating portion;
• wherein the first skirt mating portion provides a plurality of radially extending first skirt protrusions;
• wherein the second mating portion provides a plurality of radially extending second skirt protrusions;
• coupling the first crown mating portion to the first skirt mating portion;
• coupling the second crown mating portion to the second skirt mating portion;
• forming a first piston chamber that is defined, at least in part, by the crown chamber surface and the skirt chamber surface;
• rotating the crown portion generally about the crown axis to couple the crown portion to the skirt portion;
• providing a first interference between the first crown mating portion and the first skirt mating portion to inhibit axial movement of the crown relative to the skirt after coupling the first crown mating portion to the first skirt mating portion;
• providing a second interference between the second crown mating portion and the second skirt mating portion to inhibit axial of the crown relative to the skirt movement after coupling the second crown mating portion to the second skirt mating portion;
• wherein during the rotating of the crown the first crown protrusions are rotated relative to the first skirt protrusions in order to provide the first interference;
• and
• wherein during the rotating of the crown the second crown protrusions are rotated relative to the second skirt protrusions in order to provide the second interference.