Roll roundness measuring and machining apparatus and method

An apparatus for precisely machining the outer surface of a roll having oppositely disposed ends spaced along a longitudinal axis and for selectively measuring the roundness and concentricity of said outer surface, said apparatus comprising

• a plurality of spaced roll supports for rotatably supporting said outer surface;
• drive means for rotating said roll about its longitudinal axis;
• means for limiting the axial movement of said roll during rotation;
• means for machining said outer surface as it is rotated on said supports, said supports and machining means providing a centerless machining arrangement;
• a pair of locators, one of said locators mounted adjacent each of said oppositely disposed ends of said roll, said locators establishing a reference line along said roll;
• means for measuring the roundness of said outer surface as it is rotated within said supports, said measuring means comprising a plurality of displacement monitoring means for simultaneously measuring variations in the contour of said outer surface and movement of said reference line as said roll is rotated;
• means for determining the true axis of rotation of said roll, whereby a profile of said roll can be obtained by comparing roundness measurements taken at any point along said longitudinal axis to said true axis of rotation;
• and
• feedback means for periodically monitoring the changing roundness and concentricity of said other surface as it is machined.

A process for accurately measuring the roundness and concentricity of a roll having oppositely disposed ends spaced along a longitudinal axis and an outer surface with a relatively large outer diameter, said process comprising the steps of:

• rotatably supporting said outer surface of said roll on a plurality of spaced roll supports;
• mounting a pair of locators adjacent said opposite ends of said roll and determining a reference line of rotation of said roll between said locators;
• limiting axial movement of said roll along said longitudinal axis during rotation of said roll on said supports;
• measuring the roundness of said outer surface as it is rotated on said supports, said measuring means comprising a plurality of displacement monitoring means for simultaneously measuring variations in the contour of said outer surface and movement of said reference line as said roll is rotated;
• determining the true axis of rotation of said roll by calculating the mean center of said outer surface at a pair of spaced apart points along the longitudinal axis of said roll corrected for movement of said reference line as said roll is rotated;
• and
• obtaining a profile of said roll at any particular point along said longitudinal axis by comparing roundness measurements taken at such point to said true axis of rotation.

A process for precisely machining a roll having oppositely disposed ends spaced along a longitudinal axis and an outer surface having a relatively large outer diameter and for accurately measuring the roundness and concentricity of said roll, said process comprising the steps of:

• rotatably supporting the outer surface of a roll on a plurality of spaced roll supports, said supports situated to support said roll for centerless machining;
• mounting a pair of locators adjacent said opposite ends of said roll and determining a reference line of rotation of said roll between said locators;
• limiting axial movement of said roll along said longitudinal axis during rotation of said roll on said supports;
• measuring the roundness of said outer surface as it is rotated within said supports utilizing a plurality of displacement monitoring means for simultaneously measuring variations in the contour of said outer surface and movement of said reference line as said roll is rotated;
• determining the true axis of rotation of said roll by calculating the mean center of said outer surface at a pair of spaced apart points along the longitudinal axis of said roll corrected for movement of said reference line as said roll is rotated;
• obtaining a profile of said roll at any particular point along said longitudinal axis by comparing roundness measurements taken at such point to said true axis of rotation;
• and
• machining said outer surface of said roll as it is rotated on said supports.