Abstract: A cold forging process and apparatus for reinforcing an end of a rectangular tube, including a close fitting, rectangular upper mandrel that inserts into the tubing. The upper mandrel has flared corners at the end attached to the upper die. As the upper die is moved under pressure towards the lower die, the flared corners of the mandrel makes contact with the inner surface of the tube. This ensures that the tube begins to deform outward before the rest of the upper die contacts it. As the upper die is pressed towards contact with the lower die, the end of the tube is cold formed into a collar. The dies are then moved apart and the cold-formed tube removed. A lower mandrel positions and retains the die during forming. After forming the lower mandrel is used to eject the formed part, which may for instance be a trailer hitch housing.

Abstract: A cold forging process and apparatus for reinforcing an end of a rectangular tube, including a close fitting, rectangular upper mandrel that inserts into the tubing. The upper mandrel has flared corners at the end attached to the upper die. As the upper die is moved under pressure towards the lower die, the flared corners of the mandrel makes contact with the inner surface of the tube. This ensures that the tube begins to deform outward before the rest of the upper die contacts it. As the upper die is pressed towards contact with the lower die, the end of the tube is cold formed into a collar. The dies are then moved apart and the cold-formed tube removed. A lower mandrel positions and retains the tube during forming. After forming the lower mandrel is used to eject the formed part, which may for instance be a trailer hitch housing.

Abstract: A cold forging process and apparatus for reinforcing an end of a rectangular tube, including a close fitting, rectangular upper mandrel that inserts into the tubing. The upper mandrel has flared corners at the end attached to the upper die. As the upper die is moved under pressure towards the lower die, the flared corners of the mandrel makes contact with the inner surface of the tube. This ensures that the tube begins to deform outward before the rest of the upper die contacts it. As the upper die is pressed towards contact with the lower die, the end of the tube is cold formed into a collar. The dies are then moved apart and the cold-formed tube removed. A lower mandrel positions and retains the tube during forming. After forming the lower mandrel is used to eject the formed part, which may for instance be a trailer hitch housing.