CS242308B1 - The method of roughening the surface of the working rollers - Google Patents

Abstract

The invention relates to a method of roughening the surface of working rolls after mechanical grinding. In the first phase, the roll is electrospark ground until the entire surface is covered with craters after discharges, regardless of the achieved roughness parameters, and then the roll surface is shot blasted until the desired roughness parameters are achieved over the entire surface.

Description

242308

BACKGROUND OF THE INVENTION The present invention relates to a method for roughening the surface of a working roll after mechanical grinding.

So far, the most widespread method of surface roughening is the method of blasting with rolling blasting agents. O-blasting gives an unoriented, roughened or matted surface with typical toography. The roughness of such a surface depends mainly on the physical-mechanical properties of the material, i.e. the material's physical properties. cylinder, as well as the properties and kinetic energy of the blasting device. A significant defect in the rolling process is the undesirable deviations of the macroprofile, both circumferentially and along the width of the roll. Macroprofile errors such as circumferential curvature, ie. the roller blind, waviness complicated, previous abrasive roller tracks, etc. The macroprofil errors mentioned above render unsuitable the deterministic basis of the cylinder macroprofile, which is maintained by abrasion. Other disadvantages of the blasting process are the non-stationary nature, which mainly influences the variable hardness of the roller surface and the grinding of the blasting agent. They will also adversely cause abrasive surface cracks which are not removed after abrasion and move further than the centrals on the roll surface. As a result, grinding prior to blasting is a necessary but insufficient operation. Owing to the higher demands on the properties of the roughened surface of the rollers, there is no such pre-treatment of the roll surface that eliminates the abrasion deficiencies and which at the same time forms an elementary degree of homogenization of the surface microwaves before blasting.

Another, less commonly used, is the unconventional method of roughening the surface of the working rollers, which is based on electro-physical method, the so-called electro-spark machining. It uses electrical erosion to achieve a typical surface with crater topography. According to the discharge energy, roughness values of the surface to be machined can be reached. The main disadvantage of roughening the rolls in this way is the extremely long roughening times of up to several hours. a few hours of hours. Even the structural modifications of single-purpose machines cannot significantly improve this significant deficiency. It follows that the possibilities of electro-spark machining - mainly its production - are essentially in disproportion! with the intensity of the rollers in the rolling production conditions. A further disadvantage is that, in the electrospinning process, undesirably affecting the values of the cuts of the cylinder body, i.e. the concavity, the convexity, occurs in the course of roughening, in proportion to the increasing seed rate.

The above-mentioned drawbacks are reduced by the method of roughening the surface of the working rollers according to the invention. SUMMARY OF THE INVENTION The object of the present invention is to provide a surface roughening method particularly for rollers after mechanical grinding to achieve an optimum roughness of 3 to 5 µm from the rolled material head and to suppress the macrogeometric surface of the roll. In the first phase, the cylinder is electro-sparked over the craters after discharge throughout the entire flat regardless of the roughness parameters achieved, and then the surface of the cylinder is blasted to achieve the desired surface roughness.

The higher effect of the method of roughening the present invention against the prior art is to reduce the disadvantages of the individual processes and to enhance their advantages. As a consequence, there is a substantial shortening of the charge to roughen the surface of the roll. Of the initial average of 8 hours of electro-spark machining, only 3 hours are required in accordance with the invention. The time required for blasting from floods for 15 minutes to 10 minutes, which is negligible due to the longer time of electro-spark machining. Due to the shortening of the cylinder surface time, energy is saved, continuity of the manufacturing process, etc. is improved. In the first stage of machining, the cylinder is only electrically sparked. This eliminates the risk of macrogeometry and at the same time produces a frosted cratered base of the roughened surface. This machining phase is electrical. Deviations of macrogeometry are visible to the naked eye by the thyroid phase termination criterion, since there are no discharges at these visible sites. When these deviations are removed, the cylinder is covered on the entire flat discharge shock, the first machining phase is completed. At this stage, the advantages of electroprocessing in the effects on the surface of the cylinder are utilized.

The second machining stage of the prepared cylinder surface is mechanical. The finishing of the roughening according to the invention can be carried out in all types of blasting devices intended for blasting the surface of the rolls, which usually takes about 10 minutes.

The electromechanical roughening method is intended for roughening of rolling mills of rolling mills of various types and dimensions. This roughened working roller can be used for cold rolling of sheets and strips of ferrous and non-ferrous metals.

Claims (1)

SUBJECT Method of roughening the surface of working rolls after mechanical grinding, characterized in that the roll in the first phase is electro-sparkle ground for the duration of the craters after discharges throughout the flat, irrespective of the inventive roughness parameters, and then the surface of the roll is blasted until the desired roughness parameters all over the surface.