SU1683942A1 - A method of restoring mill roll surface - Google Patents

Abstract

The invention relates to the processing of pressure and can be used in rolling production of mechanical engineering. The purpose of the invention is to improve the quality of rolled products and the productivity of restoration. Above the surface of the rolls 1 plasma sources 3.4 are installed to clean the defective layer 5. The cleaned surface is deposited from sources 7.8 with rolled material 9 or an inert coating 10. The area between the rolls and the rolled material is covered with a shield 13 for protective gas or low pressure. 2 Cpfly, 1il.

Description

The invention relates to pressure treatment and can be used in rolling production of mechanical engineering.

The purpose of the invention is to improve the quality of hire and recovery performance.

The drawing shows a diagram of the surface restoration of the rolls of rolling mills.

Above the working surface of the rolls 1, interacting with the rental 2, plasma sources are installed in the following sequence; one 3 or several 4 sources for cleaning the defective layer 5, passing into a clean working surface 6; one 7 or several 8 sources for restoring the working surface by applying rolled material 9 or an inert coating 10 from the corresponding devices 11 and 12 for supplying these materials, The area of interaction of the rolls with the rolled product is covered by a screen 13, providing a protective environment or reduced pressure under it in relation to to the environment outside the screen.

The roll restoration process is being phased. At the first stage, the plasma source 3, for example, the plasma torch 1 is installed at an angle optimal for removing the defective layer 5 from the working surface of the rolls 1 with an inert (argon) plasma beam, and remove it. If the defective layer cannot be removed from once to the level of a clean working surface 6, additional sources 4 will be used.

The plasma torch operating mode is selected based on the thickness of the defective layer, and it is desirable to select the number of plasma sources based on the temperature regime of processing of rolled metal 2 and its configuration. For example, for sheet metal products made of aluminum with a thickness of 100 μm, one plasma torch (or one row across the sheet) is used with the following operating modes: discharge voltage - 200-300 V: discharge current 80-150 A; the working fluid of the plasma torch is argon: the thickness of the defective layer of rolls is not more than 10 microns.

At the second stage, a plasma source 7 is used, for example, a plasma torch, which is installed at an angle optimal for restoring the working surface by applying the rolled material 9 in the form of powder from the device 11. In some cases, namely when rolling aluminum, it is advisable to use an inert coating 10 — oxide aluminum, feeding it in the form of a powder (particle size of not more than 0.1 μm) from the device 12; in case of poor adhesion between the clean roll surface and the reconditioned coating, it is advisable to use additional plasma sources 8 for applying an intermediate sublayer. Using the screen 13 allows you to work in a closed environment, for example, argon or under reduced pressure, for example, up to 10-11 Pa, significantly reducing the amount of impurities that affect the quality of the rental.

The plasma devices act on the working surface of the rolls, cleaning it of the defective layer, and then restore it by applying a layer of material that does not interact with the rolled surface, which corresponds to the original roll sizes. This allows not only to exclude the formation of surface defects of both the rolls and the finished product due to the exclusion of interaction with a chemically active medium - electrolyte, but also to exclude the possibility of foreign material from the surface layer of the rolls getting on the surface of the rolled product. Moreover, the required rental profile keeps its dimensions constant.

When several, for example, three plasma devices are used, two sources are used for cleaning, guaranteeing a clean surface for restoration of a given layer, while eliminating its defects during plasma deposition due to the fact that one source removes the defective layer and the other performs final cleaning under applying a new layer.

Alternating the work of plasma sources, it is possible to selectively clean and restore the contacting layer of the rolls, to adjust their temperature, which allows you to roll complex profiles.

The use of a protective medium, for example, argon or low environmental pressure, helps to reduce the likelihood of the formation of additional chemical compounds both on the working surface of the rolls and on the surface of the car.

The invention compares favorably with the prototype in that it improves the quality of rolled products, increases the service life of the rolls, controls the temperature of the rolled products, compensates for the wear of the supports of the rolls of rolling mills, and improves recovery performance.

Claims (3)

Claim 1. A method of restoring the surface of the rolls of rolling mills, including removing the defective layer from the surface of the rolls 5 during the rolling process, characterized in that, in order to improve the quality of the rolled reduction productivity, 5 recovery layer is sprayed on the surface of the roll with the defective layer removed or surfacing, while applying the recovery and removal of the defective layers is carried out by a plasma jet with equal speeds. 2. The method according to claim 1, characterized in that the removal of the defective and the application of the recovery layer by a plasma jet is carried out in a protective environment. 3. The method according to claim 1, with the fact that the removal of the defective and the application of the recovery layer by a plasma jet is carried out under reduced pressure.