摘要 |
A roll forging machine has a pair of opposed work rolls carrying cooperating dies and a pair of support rails mounted on each work roll on opposite sides of the die thereon. The support rails provide the work rolls with a high spring constant, so that the supporting framework can have a relatively low spring constant. During forging the work rolls are urged together with a force substantially greater than the force required to forge the workpiece, and the opposed support rails are pressed together to prestress the work rolls. The dies and support rails occupy only preselected segments of the circumferences of the work rolls, and a pair of backup rolls bear against each work roll on the balance of the circumference. The two backup rolls for each work roll are positioned asymmetrically with respect to the plane of the workpiece, with the backup roll on the feed side of the work roll being located farther away from the plane of the workpiece than is the other backup roll. One hydraulic cylinder urges the two work rolls together, and a second hydraulic cylinder urges the workpiece into the work rolls, with a constant ratio being maintained between the pressures applied by the two hydraulic cylinders.
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