SU1232306A1 - Method of producing thick sheets - Google Patents

Description

The invention relates to rolling production, in particular to the manufacture of thick sheets and plates.

The purpose of the invention is to increase the yield.

The method is carried out as follows.

Ingots rolled on a slabing. From the roll - out from the side of the corresponding bottom part of the ingot, the end

roll with complete removal of the weft from the bottom side is 98.8; 97.7; 99.0% of the length of the stock, formed respectively from uncut, 35, 30 and 25% of the defective part with bottom weat. The table shows the data justifying the need for rolling on a reversible plate mill to produce the initial 25-45% of absolute reduction in such a way that it is defective.

the part with the defect is the bottom weave, the part of the slab with incomplete removal of the part of the slab corresponding to the bottom weigher was in its length 65-75% in the direction of rolling, ki along the longitudinal axis of the slab. A billet with an incompletely removed bottom weigher is rolled on a reversible plate mill. five

Rolling is carried out in such a way that the workpiece is set in the mill by the defective part (with the arm not fully removed) forward in the rolling direction. To do this, after each pass, the workpiece is turned over by 180 °, and this operation is carried out before the workpiece is crimped by 25-45% of absolute reduction. Then, rolling is carried out reversibly without turning the workpiece to the finished sheet.

When cutting the bottom defective part of a roll out with a bottom weigher less than 25 to 65% of its total length, for example 60%, and subsequent rolling on a reversible plate mill, provided that when crimping the initial 25-45% of absolute reduction, the workpiece is set to Thus, the defective part of the slab (with an incompletely distant bottom suturing) is in the front part during rolling, the length of the face cut of the sheet stock from the bottom side with the complete removal of the defective part (sling) is 109.0% of length of roll 35 percent of the bottom non-cut 35% of the bottom part is defective, that is, 9.0% of the trimming is formed from the good part of the slab. When cutting off the bottom defective part of the soft roll, more than 75%. its length, for example, 80%, and provided that Q subsequent rolling on a reversible plate mill according to the indicated technology, the length of the end trimmings of the sheet stock from the bottom side with the complete removal of the defective part (arm) is 113.1% of the length of the stock that received of the uncut 45% of the bottom defective part, i.e., 13.1% of the cut is formed from the suitable part of the slab.

When cutting the bottom defective part of a roll out with bottom weighting for 65, so 70 and 75% of the length of the bottom weigher and during subsequent rolling of the workpiece, on a reversible plate mill, provided that with the initial 25-45% of absolute reduction, the workpiece is set in the mill so that the defective part of the sl - 55 ba (with an incompletely removed bottom weigher) is in the front part during the rolling, the length of the face trim of the sheet

roll with complete removal of the weft from the bottom side is 98.8; 97.7; 99.0% of the length of the stock, formed respectively from uncut, 35, 30 and 25% of the defective part with bottom weat. The table shows the data justifying the need for rolling on a reversible plate mill to produce the initial 25-45% of absolute reduction in such a way that it is defective.

 a part of the slab with an incompletely removed bottom weigher was in its front part in the direction of rolling,

When cutting off the defective part of a roll out with bottom weigher by 65-75% of its length and then rolling the billet on a plate reversing mill according to options 5-9 (table), the length of the face cut of the sheet stock with complete removal of the weave from the side, the corresponding bottom part of the ingot with an incompletely removed weft constitutes 89.8-91.0% of the length of the end edge of the sheets laminated by a known method. For comparison, the length of the face trim of sheets rolled by a known method is taken as 100%. When the initial absolute reduction on a plate mill is reduced or increased, for example, to 5 and 70%, respectively, when the workpiece is set to an anterior defective mill By the hard part, the size of the face cut of the sheet roll from the side corresponding to the bottom part of the ingot increases to 98.8 and 99.8%, respectively, which is 8.8–9.0% more than during rolling by the proposed method.

Rolling ingots at the blooming mill, removing the defective end of the billet with bottom weigher for 65-75% of the length of this defect and further rolling on the plate reversing mill when the initial 25-45% of the absolute reduction is carried out so that the defective part of the billet is incompletely the remote weft was placed in its front part in the direction of rolling, allows you to form the face cut of the uncut defective metal and reduce the size of the end cut of the rolled sheet from the side corresponding to the bottom part STI ingot 9.0-10.2%, which indicates the effectiveness of the proposed method.

Example. At the blooming mill, two ingots weighing 20 tons each are rolled into slabs

five ,.

50

preparations with a section of 220X1760 mm. The length of each roll is 6520 mm. From the bottom part of a single roll, the defective part (bottom outlet) is completely cut off. The cut length is 195 mm. From the second roll, the length of the bottom weft of which is also 195 mm, the defective part of a length of 1.35 mm is cut off, which is 70% of the entire defective bottom part (i.e., the length of the entire bottom weft).

Both slabs are reheated and rolled on a single plate reversible plate mill into sheets with a cross section of 70X XI700 mm.

A slab with a completely removed bottom defective part is rolled by a known method, and the slab in the mill is set alternately at both ends forward in the direction of rolling.

With an incompletely removed bottom weigher, the first three passes of the bottom forward defective part are set in the mill in the direction of rolling. For this purpose, before the second and third pass, the valve is 180 °. The compression in the first three passes is 60 mm, which is 40% of the absolute compression.

The length of the end trimmings of the sheet roll with complete removal of the weft rolled by the proposed method is 165 mm on the bottom side, which is 90.9% of the length of the front side of the sheet on the sheet rolled by a known method.

In the proposed method, the butt cut of the sheet roll from the side corresponding to the bottom part of the ingot is 9.1% less than that of the B known. In addition, this trim in the proposed method is formed from the defective part of the slab, which is not knowingly cut off after rolling on the squeeze mill.

Claims (1)

METHOD FOR PRODUCING THICK SHEETS, including rolling an ingot on a crimping mill, cutting a defective end of a workpiece, final rolling on a thick sheet mill and cutting a sheet ends, characterized in that, in order to increase the yield, a piece of a defective end of a workpiece is carried out partially 65-75 % of the length of the defect, and when rolling on a plate mill, the initial 25–45% of the absolute compression is carried out with a blank of the workpiece after each pass. s e