1. The ring rolling process typically begins with upsetting of the starting stock on flat dies at its plastic deformation temperature - in the case of grade 1020 steel, approximately 2200 degrees Fahrenheit. |
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2. Piercing involves forcing a punch into the hot upset stock causing metal to be displaced radially, as shown by the illustration. |
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3. A subsequent operation, shearing, serves to remove the small punchout ... |
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4. ...producing a completed hole through the stock, which is now ready for the ring rolling operation itself. At this point the stock is called a preform. |
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5. The doughnut-shaped preform is slipped over the ID roll shown here from an "above" view. |
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6. A side view of the ring mill and preform workpiece, which squeezes it against the OD roll which imparts rotary action... |
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