The project
The customer's design called for a rotor shaft forging with consistent radial soundness and grain flow along its full 4.2-meter length — a part this size and slenderness needs enough upset-and-draw working, not just enough press tonnage, to actually refine the coarse as-cast structure evenly from end to end rather than leaving an undeformed core in the middle third of the bar. The billet was upset to reduce its length-to-diameter ratio before the first draw-out pass specifically to guarantee adequate deformation ratio through the section, then drawn out in a sequence of press strokes with intermediate reheats to keep the working temperature within the ideal heavy-forging range throughout.
Ultrasonic testing after rough forging confirmed uniform internal soundness along the full shaft length, with no indications exceeding the customer’s specified acceptance criteria — the rough forging shipped for outside machining and heat treatment per the customer’s own downstream process.
