Upsetforging

Upset forging is the forging process where it increases the diameter of the work piece by compressing its length.

Finish products of Upset Forging

Engine valves

Bolts

Screws

- usually done in special high-speed machines called crank presses

- The initial workpiece is usually wire or rod but some machines can accept bars up to 25 cm (9.8 in) in diameter and a capacity of over 1000 tons.

- standard upsetting machine employs split dies that contain multiple cavities

Process

• The dies open enough to allow the work piece to move from one cavity to the next.

• the dies then close and the heading tool, or ram, then moves longitudinally against the bar, upsetting it into the cavity

• If all of the cavities are utilized on every cycle, then a finished part will be produced with every cycle, which makes this process advantageous for mass production.