Computer controlled rolling mill

Claim 2

In a method of reducing the thickness of metal by rolling the metal between at least one set of rollers wherein rolling parameters for a rolling pass are determined in association with a digital computer system by access to stored information representing the variation of said rolling parameters as a function of diverse metal characteristics, the improvement comprising storing the magnitude of a rolling parameter selected from the group consisting of power and force as a function of the thickness of the metal for a chosen per unit draft taken by said rollers, storing the ratio of said selected parameter for an actual reduction to said selected parameter for the chosen per unit draft as a function of the deformation of the rolled metal, determining the value of said parameter at the chosen per unit draft for a desired output thickness and the value of said parameter ratio for a desired deformation and setting said parameter for the succeeding rolling pass at the arithmetic product of said determined values.

Claim 3

In a method of reducing the thickness of metal by rolling the metal between at least one set of rollers wherein rolling parameters for a rolling pass are determined in association with a digital computer system by access to stored information representing the variation of said rolling parameters as a function of diverse metal characteristics, the improvement comprising storing the magnitude of a rolling parameter selected from the group consisting of power and force as a function of the thickness of the metal for a chosen per unit draft taken by said rollers, storing the ratio of said selected parameter for an actual reduction to said selected parameter for the chosen per unit draft as a function of the deformation of the rolled metal, determining the value of said parameter at the chosen per unit draft for a desired output thickness and the value of said parameter ratio for a desired deformation and setting said parameter for the succeeding rolling pass at the arithmetic product of said determined values.

Claim 4

In a method of reducing the thickness of metal by rolling the metal between at least one set of rollers wherein rolling parameters for a rolling pass are determined in association with a digital computer system by access to stored information representing the variation of said rolling parameters as a function of diverse metal characteristics, the improvement comprising storing the magnitude of a rolling parameter selected from the group consisting of power and force as a function of the thickness of the metal for a chosen per unit draft taken by said rollers, storing the ratio of said selected parameter for an actual reduction to said selected parameter for the chosen per unit draft as a function of the deformation of the rolled metal, determining the value of said parameter at the chosen per unit draft for a desired output thickness and the value of said parameter ratio for a desired deformation and setting said parameter for the succeeding rolling pass at the arithmetic product of said determined values.

Claim 5

A method of reducing the thickness of metal according to claim 1 wherein said selected parameter is force, said force being stored as a function of inverse output thickness for an associated temperature value and said force ratio being stored as a function of the elongation of the rolled metal.

Claim 6

A method of reducing the thickness of metal according to claim 2 further including modifying the arithmetic product of force at the chosen per unit draft and temperature for a desired inverse output thickness and force ratio for a desired elongation by factors proportional to thE width, hardness and estimated temperature of the metal before setting the force for the succeeding rolling pass.

Claim 7

A method of reducing the thickness of metal according to claim 1 wherein said selected parameter is power, said power being stored as a function of inverse output thickness for an associated temperature value and said power ratio being stored as a function of the elongation of the rolled metal.

Claim 8

A method of reducing the thickness of metal according to claim 4 further including modifying the arithmetic product of said power ratio and said power for a chosen per unit draft and temperature by factors proportional to the width, hardness, estimated temperature and speed of the mill before setting the power for the succeeding rolling pass.

Claim 9

In a method of reducing the thickness of metal by rolling the metal between at least one set of rollers wherein predicted rolling parameters for a pass of the metal through the rollers are determined in association with a digital computer system by access of stored families of functions defining relationships between various rolling parameters as functions of metal characteristics, the improvement comprising defining a rolling parameter selected from the group consisting of power and force by a first family of functions describing the ratio of the value of the selected parameter for actually contemplated rolling conditions to the value of the selected parameter for a chosen per unit draft as a function of metal deformation for diverse output thicknesses, said family of functions being characterized by a common intersection at the chosen per unit draft, defining said selected parameter as a function of the magnitude of said selected parameter for said chosen per unit draft against the thickness of the metal from the stand for various associated temperatures, accessing said stored functions to determine the magnitude of said selected parameter at the chosen per unit draft for a desired output thickness and the ratio of the selected parameter for a desired deformation, and setting the selected parameter for the rolling pass at the arithmetic product of said magnitude and said ratio as determined from said functions.

Claim 10

In a method of reducing the thickness of metal by rolling the metal between at least one set of rollers wherein predicted rolling parameters for a pass of the metal through the rollers are determined in association with a digital computer system by access of stored families of functions defining relationships between various rolling parameters as functions of metal characteristics, the improvement comprising defining a rolling parameter selected from the group consisting of power and force by a first family of functions describing the ratio of the value of the selected parameter for actually contemplated rolling conditions to the value of the selected parameter for a chosen per unit draft as a function of metal deformation for diverse output thicknesses, said family of functions being characterized by a common intersection at the chosen per unit draft, defining said selected parameter as a function of the magnitude of said selected parameter for said chosen per unit draft against the thickness of the metal from the stand for various associated temperatures, accessing said stored functions to determine the magnitude of said selected parameter at the chosen per unit draft for a desired output thickness and the ratio of the selected parameter for a desired deformation, and setting the selected parameter for the rolling pass at the arithmetic product of said magnitude and said ratio as determined from said functions.

Claim 11

A method of reducing the thickness of metal according to claim 6 further including measuring the actual parameter at the stand during rolling and adaptively updating only the stored curve defining the magnitude of said parameter for the chosen per unit draft as a function of the output thickness, said adaptive updating of said curve being an amount proportional to the difference between the actually measured parameter and the existing stored functions.

Claim 12

A method of reducing the thickness of metal according to claim 7 further including modifying the measured parameter by an amount proportional to the width, hardness and temperature of the metal being rolled, prior to updating of said functions.

Claim 13

A method of reducing the thickness of metal according to claim 7 wherein said selected parameter is power and further including measuring the actual power during rolling and adaptively updating only the stored curve defining the magnitude of power for the chosen per unit draft as a function of output thickness, said adaptive updating of said magnitude curve being an amount proportional to the difference between the actually measured parameter and the existing stored functions.

Claim 14

A method reducing the thickness of metal according to claim 9 further including modifying the measured power by an amount proportional to the width, hardness and temperature of the metal and speed of the stand prior to updating of said stored functions.

Claim 15

A computer controlled method of rolling metal by passing said metal between a pair of confronting rollers whereby the incoming thickness, and therefore the amount of reduction, of said metal required to achieve a desired magnitude of force for a given output thickness can be predicted, said method comprising determining the temperature of the metal being rolled, accessing Stored data depicting the variation of force for a predetermined percentage draft as a function of output thickness to determine the normalized force required to obtain the desired output thickness, calculating the ratio of the actual force to be applied at said stand to the normalized force, accessing stored data depicting the relationship between the ratio of actual force to the normalized force as a function of a metal deformation factor selected from the group consisting essentially of elongation and per unit draft to determine the quantity of metal deformation produced by the calculated force ratio and determining the incoming thickness of said metal from said metal deformation and said output thickness.

Claim 16

A computer controlled method of rolling metal by passing said metal between a pair of confronting rollers whereby the incoming thickness, and therefore the amount of reduction, of said metal required to achieve a desired magnitude of force for a given output thickness can be predicted, said method comprising determining the temperature of the metal being rolled, accessing Stored data depicting the variation of force for a predetermined percentage draft as a function of output thickness to determine the normalized force required to obtain the desired output thickness, calculating the ratio of the actual force to be applied at said stand to the normalized force, accessing stored data depicting the relationship between the ratio of actual force to the normalized force as a function of a metal deformation factor selected from the group consisting essentially of elongation and per unit draft to determine the quantity of metal deformation produced by the calculated force ratio and determining the incoming thickness of said metal from said metal deformation and said output thickness.

Claim 17

A method of rolling metal according to claim 10 further including adjusting the normalized force by an amount dependent upon the width and hardness of the metal being rolled before calculating said force ratio.

Claim 18

A computer controlled method of rolling metal by passing said metal between a pair of confronting rollers whereby the incoming thickness, and therefore the amount of reduction, of said metal required to achieve a desired magnitude of power for a given output thickness can be predicted, said method comprising determining the temperature of the metal being rolled, accessing stored data depicting the variation of power for a predetermined percentage of draft as a function of output thickness to determine normalized power required to obtain the desired output thickness, calculating the ratio of the actual power to be applied at said stand to the normalized power, accessing stored data depicting the relationship between the ratio of actual power to the normalized power as a function of a metal deformation factor selected from the group consisting essentially of elongation and per unit draft to determine the quantity of metal deformation produced by the calculated power ratio and determining incoming thickness of said metal from said determined metal deformation and said output thickness.

Claim 19

A computer controlled method of rolling metal by passing said metal between a pair of confronting rollers whereby the incoming thickness, and therefore the amount of reduction, of said metal required to achieve a desired magnitude of power for a given output thickness can be predicted, said method comprising determining the temperature of the metal being rolled, accessing stored data depicting the variation of power for a predetermined percentage of draft as a function of output thickness to determine normalized power required to obtain the desired output thickness, calculating the ratio of the actual power to be applied at said stand to the normalized power, accessing stored data depicting the relationship between the ratio of actual power to the normalized power as a function of a metal deformation factor selected from the group consisting essentially of elongation and per unit draft to determine the quantity of metal deformation produced by the calculated power ratio and determining incoming thickness of said metal from said determined metal deformation and said output thickness.

Claim 20

A method of rolling metal according to claim 13 further including adjusting the normalized power by an amount proportional to the width and resistance to deformation of the metal being rolled and the speed of the stand prior to calculating said power ratio.

Claim 21

An automated rolling mill comprising at least one rolling stand having a pair of confronting rollers, means for adjusting the openings between said rollers, and a computer control system having means defining a parameter selected from the group consisting of power and force by a first family of curves defining the ratio of the parameter magnitude for a chosen per unit draft as a function of elongation, said family of ratio curves being characterized by a common intersection at the chosen per unit draft, means defining said parameter for a chosen per unit draft as a function of the output thickness of metal passed through said stand, means for accessing said stored curves to determine both the value of the parameter for the chosen per unit draft required to produce a desired output thickness in metal passed through said rollers and the value of said ratio for a given elongation, means for calculating the arithmetic product for said values as determined from said curves, and means for predicting the selected parameter at said mill at the arithmetic product of said values.

Claim 22

An automated rolling mill comprising at least one rolling stand having a pair of confronting rollers, means for adjusting the openings between said rollers, and a computer control system having means defining a parameter selected from the group consisting of power and force by a first family of curves defining the ratio of the parameter magnitude for a chosen per unit draft as a function of elongation, said family of ratio curves being characterized by a common intersection at the chosen per unit draft, means defining said parameter for a chosen per unit draft as a function of the output thickness of metal passed through said stand, means for accessing said stored curves to determine both the value of the parameter for the chosen per unit draft required to produce a desired output thickness in metal passed through said rollers and the value of said ratio for a given elongation, means for calculating the arithmetic product for said values as determined from said curves, and means for predicting the selected parameter at said mill at the arithmetic product of said values.