GB923619A - Improvements in or relating to the dividing of rolled stock into definite lengths - Google Patents

Abstract

923,619. Length measuring. SCHLOEMANN A.G. June 16, 1961 [June 18, 1960], No. 21880/61. Class 106 (2). [Also in Group XXII] A method of dividing finished lengths of rolled stock into commercial lengths or into cooling bed lengths by means of shears arranged beyond a continuous rolling mill train, characterized in that the finished lengths are measured by measuring the transit time of the strand at the beginning of the train of rolls by means of an impulse frequency generated synchronously with the speed of revolution of the last finishing roll stand, then dividing the measured finished lengths by calculation into commercial lengths or cooling bed lengths, by sub-dividing the number of impulses corresponding to the transit time of the finished length into smaller partial numbers which correspond to the commercial lengths or to the cooling bed lengths and finally cutting the finished lengths into commercial lengths or into cooling bed lengths corresponding to the calculated partial numbers. A continuous mill train 2, 3, 4 is followed by a shear 5 and a cooling bed 6. Beside the first roll stand is a photo-electric cell A and beyond the shear 5 are two photo-electric cells B, C, at least one of which is displaceable in the direction of rolling. An impulse emitter 8 is connected to the last roll stand. When the leading end of a billet passes the cell A a circuit is completed between the emitter 8 and a counting mechanism 16 and the circuit is broken when the end of the billet passes the cell A so that the number of impulses measured by the counter 16 is proportional to the length of the billet and hence to the finished length of the rolled strand. When the tip of the finished length passes the photo-electric cell B a circuit is completed, through a gate circuit T, between the impulse emitter 8 and a counting mechanism 14 which counts the impulses until the tip passes the cell C. The information from each counter is passed to a computer C which controls the shear 5 to cut the strand into cooling bed lengths which are each an integral multiple of the length X (a predetermined commercial length), and which are between the maximum and minimum lengths which can be handled by the cooling bed, and one further cooling bed length which is greater than an integral multiple of the length X by an amount less than the length X. In a modification (Fig. 2, not shown), the apparatus is arranged to measure the length of a bloom and hence calculate the finished length, and a computer controlling the shear cuts the finished strand into billets of equal length. Alternatively, the cutting programme may be arranged to trim the leading end of the strand so that the remainder may be cut into a number of billets of a predetermined length.