METHOD FOR CONTROLLING LUBRICATING OIL SUPPLY RATE IN COLD ROLLING

PURPOSE:To permit the adequate and automatic control of a lubricating oil supply rate for every coil unit by subjecting the reference supply rate of the lubricating oil determined from the functions of rolling force and rolling distance of cold rolling to correction with the coefft. of friction calculated from the values measured with a rolling force meter, etc. during rolling. CONSTITUTION:The reference supply rate R1 of the lubricating oil is determined by a control device 7 from the data on the rolling distance by the revolution pulses of a rolling motor 4 with regard with a cold rolling material 1 and work rolls 2 and the rolling force 5 measured with the rolling force meter 5. On the other hand, the coefft. mu0 of friction is calculated in a control device 8 by adding a steel kind, size, etc. to the approximation expression I of Hill by the stable rolling force P based on the experience on rolling. The lubricating oil supply rate R2 is calculated in the control device 8 by the equation II which subjects the coefft. mu of friction determined by the equation I from the rolling force 5 and revolution pulses 4 during the actual rolling of the coil and the tension correction term of the tension meter 6 to the addition with the correction term alpha for every stand. The oil is supplied at such rate from a flow rate control device 9. The lubricating oil supply rate for each coil is thus made adequate with regard to the reference coil of that steel kind and size, by which the product is stabilized.