Flow-forming machine and method for flow-forming

A method of flow-forming a substantially rotation-symmetric workpiece having a drum-shaped circumferential portion, the method comprising:

• providing a flow-forming machine comprising
• a spindle which can be driven in rotation about a spindle axis,
• a clamping device which is arranged on the spindle and has a plurality of clamping elements which are adjustable between a clamping position, in which the clamping elements abut against an outer circumferential region of the workpiece with a predetermined clamping force and hold the workpiece on the spindle for forming, and a release position, in which the clamping elements are spaced from the workpiece in a defined manner for releasing the workpiece from the spindle, by means of a first actuating device, wherein the clamping force for holding the workpiece on the spindle during forming can be applied by the first actuating device,
• a plurality of forming rollers which are axially feedable to the drum-shaped circumferential portion of the workpiece and are radially and axially feedable for forming the circumferential portion of the workpiece,
• a second actuating device on the clamping device, by means of which a position of the clamping elements can be set in a radial direction for adapting to a diameter of the workpiece, and
• a control device, by means of which the second actuating device can be actuated depending on the diameter of the workpiece to be formed, wherein the clamping elements are radially pre-positioned depending on the diameter of the workpiece,
• clamping the workpiece to the spindle by means of the clamping device,
• driving the spindle in rotation about the spindle axis, and
• radially and axially feeding the plurality of forming rollers to the workpiece for forming the circumferential portion,
• wherein
• the second actuating device is configured to adapt the position of the clamping elements to the diameter of the workpiece, and
• the control device is configured to actuate the second actuating device depending on the diameter of the workpiece to be formed, so that the clamping elements are radially pre-positioned depending on the diameter of the workpiece.