SU845903A1 - Method of forming shape of sheet rolling mill rolls - Google Patents

Description

(54) METHOD OF PROFILING ROLLS FOR SHEET MILLS

The invention relates to metallurgy. in particular for sheet rolling production

A known method of roll profiling includes grinding work and support rolls with predetermined profiles ensuring good contact of work and support rolls (absence) of gaps in the middle between the work roll and support roll) and changing the profile of work rolls for the campaign of work rolls to compensate for their wear , because during one campaign of support rolls, the work rolls change 20-30 times 1.

The disadvantage of this method of roll profiling is that the desired distribution of roll-over pressures in the zone of contact between the work rolls and support rolls exists only on new work rolls and support rolls, and as they develop, stress concentrations in different parts of the work rolls and support rolls leading to to vykrorkamku support rolls and their premature release from the line.

There is also known a method of profiling rolls of sheet rolling mills, which consists in the fact that the profile of the support roll

make equidistant lines approximating the profile of a worn-out work roll with regard to its thermal expansion 2

The disadvantage of this method is that in cases where the support roll wears more intensely in between

over than along the edges, high centering of the inter-roll pressure occurs at various points on the surface of the rolls, leading to the occurrence of chipping on the support rolls and their exit from the station.

10 When the worn work rolls t have a constant shape and an anvil block

in the middle it does not work out like this

It happens in most cases with the proc: 1tke thick sheets on reversing mills and in a series of roughing stands of continuous strikes,

IS this support roll provides: jurmal mill operation. In those cases when the wear pattern of the work rolls depends on a variety of factors, and the supporting ribs wear out more in the middle, which 6i when rolling thin sheets, especially

20 in the cages in which the system is operating; we have a hydraulic adjustment of the strip profile, the anvil roll does not ensure the normal operation of the mill, since chippings appear on its surface, which can lead to the rolls leaving the building.

The purpose of the invention is to reduce the consumption of rolls.

This goal is achieved by the fact that, according to the method involving grinding the work rolls and support rolls, the profile of the worn support rolls is periodically measured directly in the stands, and annular recesses are made on the surface of the work rolls at the places corresponding to the convexities on the support rolls, grooves equal to the height of the bumps of the support rolls.

FIG. Figure 1 shows an example of changing a shaft between work rolls and support rolls in different stages of the support roll campaign; in fig. 2 - the form of the proposed profiling of the work rolls in combination with the developed profile of the support rolls.

FIG. 1a shows the profiles of the new support 1 and working 2 rolls when filling into the cage after grinding. Such a roll profile ensures uniform distribution of contact stresses, ensuring normal rolling. However, at the end of the campaign, the work rolls on the backup rolls will be mined. The developed profile of the support rolls and the new profile of the work rolls are shown in FIG. 1 b. Here, in the area of the annular protrusions 3 formed as a result of the wear of the support rolls, the concentration of contact pressures is obtained, which increases towards the end of the campaign of workers and support rolls, as the gap between the work roll and the support roll in the middle along their length increases (Fig. 1c) . The size and location of the annular protrusions that occur when the support rolls wear out can not be predicted without periodic measurements, since their formation depends on many factors: sheet gauge thickness and width for each campaign of work rolls, initial roll profiling, crimping mode, bending mode, and t Since the rate of formation of irregularities on the support roll is small and is 0.03-0.04 mm / day, the measurement of the profile of the worn support rolls can be done every shift in & time of routine inspections of the camp. If you measure the profile of the support roll during short stops of the mill for handling rolls or during routine inspection of the mill, you can determine the location

and the size of the annular protrusions at the beginning of their formation and on the work rolls to make annular grooves commensurate with these convexes, which is not difficult for the grinding machines used. The profile of the rolls gives a uniform plot of contact roll pressure (Fig. 2), and there are no flashes from the support rolls, which prolongs their service life.

The method is carried out as follows.

Grind support rolls with two conical bevels, and work rolls - cylindrical with trough-shaped bevels along. Rolls poured into the working cage. After 8-10 hours of operation, the profile of the support rolls is measured directly in the mill stand with a special device. The work rolls are polished to the next transshipment with ring grooves in places corresponding to the bulges appearing on the support rolls.

The economic effect of the proposed method of roll roll forming is obtained by increasing the service life of expensive support rolls.

Claims (2)

1.Saf M. MM rolling wideband steel. 1969, p. 459. 2. USSR author's certificate number 400389, cl. B 21 B 27/02, 1973. Support Ba / iQK Working 6o / IDK