Investigation into the rolling of profiled rings

• Main Author: Moussa, G.
• Published: University of Manchester 1981
• Subjects: 670; Industrial rolling techniques
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379717

Three aspects of ring rolling are investigated in this thesis, single stage closed-pass rolling, multi-stage rolling and radial-axial rolling. In Chapter Two, which deals with single stage closed-pass rolling, the rolling of a range of symmetrical and non-symmetrical profiles is investigated., The effects of feed rate, lubrication, small variations in the geometry of the roll and blank shape on profile filling are examined experimentally. The occurrence of defects and surface cracking and the stability of rolling when producing non-symmetrical profiles are examined. Rolling force and torque are predicted theoretically and comparisons with experimental results are made. In Chapter Three the production of a bicycle rim is investigated, following an enquiry from a cycle manufacturer. A multi-stage ring rolling operation is employed. The problems of profile filling, cracking and surface finish are solved. 'Means of providing stability to the rolling process and diameter control are developed and tested. The circumference is controlled to within 1 mm with radial thickness variations within 1% of the specified thickness. Various aluminium alloys and a magnesium alloy are used as test materiaLs. A theory for the dimensional limitations in relation to profile folding in the final stage is given. In Chapter Four a newly installed experimental axial rolling system is described. The system was designed and manufactured in the Department and it was provided with control and measuring equipment. Stability of the rolling process is examined theoretically and experimentally for axial and radial-axial ring rolling operations and the control system is examined. Rolling force and torque and power dissipation are predicted theoretically and compared with experimental results.