RU2793641C1 - Cast roll treatment method - Google Patents

Abstract

FIELD: treatment of a cast roll.

SUBSTANCE: pre-treatment of cast roll with a cutting tool is carried out with length feed. The cast roll and the brush are installed in contact with placement of their longitudinal axes in the same plane. The periphery of the brush is brought into contact with a bar made of wear-resistant material, ensuring a state of mutual wetting at the point of contact. The coating is applied to the cast roll by rotating the brush and the cast roll and their mutual movement along the longitudinal axis. The angular velocities of the cast roll and the brush are set in such a way that their linear velocities at the point of their contact are equal. The speed of mutual movement of the cast roll and the brush along the longitudinal axis is set equal to the speed of the longitudinal feed of the cutting tool.

EFFECT: surface quality of the cast roll coating is improved.

1 cl, 1 dwg, 1 ex

Description

The invention relates to rolling production, in particular to rolls of rolling mills, and can be used to prepare their working surface before rolling.

A known method of manufacturing rolling rolls, including installation with contact of a roll and a brush with a metal pile with the placement of their longitudinal axes in the same plane, bringing the periphery of the pile of the brush into contact with a heated bar of the coating material, applying a wear-resistant coating to the roll by mutual rotation and mutual movement along the longitudinal axis of the brush and roll, and the amount of slip is smoothly adjusted during coating by changing the angle of the brush in the direction of its movement (U.S. Pat. RF 2353447, V21V 28/02).

The disadvantage of the known method is the low quality of the coating of the rolling roll, due to the fact that the sliding of the bristle of the brush and the surface of the rolling roll at the point of contact does not provide complete coverage of the irregularities of the roll profile. This is due to the fact that this method does not allow you to adjust the amount of slip, but only changes its direction.

The closest analogue of the claimed invention is a method for processing rolls, including installation with a roll contact processed by a cutting tool to obtain a known profile, and brushes with a metal bristle with their longitudinal axes in the same plane, bringing the periphery of the bristle of the brush into contact with a bar made of a wear-resistant coating material in a state of mutual wetting at the point of contact, applying a wear-resistant coating on the roller by rotating the brush and roller and their mutual movement along the longitudinal axis (U.S. Pat. RF 2346767, B21B 28/02).

The disadvantage of the proposed method is the low quality of the roll surface coating. This is due to the fact that due to the difference in the linear velocities of the periphery of the brush and the surface of the rolling roll at the place of their contact, the coating material is “cut off” from the periphery of the bristle of the brush, which does not ensure the completeness and quality of the applied coating.

The technical problem of the proposed method is to increase the life of the rolling roll.

The technical result consists in improving the quality of the surface of the rolling roll coating by eliminating sliding in the vertical and horizontal directions at the point of contact between the periphery of the brush pile and the rolling roll.

The problem is solved by the fact that in the method of processing rolls, including pre-treatment of the roll with a cutting tool, installation with contact between the roll and the brush with their longitudinal axes in the same plane, bringing the periphery of the brush into contact with a bar made of wear-resistant material, in state of mutual wetting at the point of contact, coating the rolling roll by rotating the brush and the rolling roll and their mutual movement along the longitudinal axis, according to the invention, after pre-treatment of the rolling roll, the angular velocities of the rolling roll and the brush are set so that their linear velocities in place their contacts were equal, while the speed of mutual movement of the rolling roll and brush along the longitudinal axis is set equal to the speed of the longitudinal feed of the cutting tool.

The quality of the coating application largely depends on its installation. This is achieved not only by manufacturing a roll profile, the contour of which maximally corresponds to the contour of a drop or a whole number of drops of the coating material (according to the prototype), but also by the completeness of the “filling” of the profile depressions with the coating material. In order to exclude the "cutting" of the coating material by the profile contour of the rolling roll from the periphery of the brush pile, as well as to ensure the completeness of the "laying" of the coating into the profile cavities, it is necessary to eliminate sliding at the point of contact between the periphery of the brush pile and the roll, both in the vertical direction and in horizontal.

To eliminate vertical sliding, the angular speeds of rotation of the brush and roll are calculated so that, for given diameters of the brush and roll, the linear speeds at the point of their contact are equal.

To eliminate horizontal slip, the speed of mutual movement of the brush and the rolling roll along the longitudinal axis is set equal to the speed of the longitudinal feed of the cutting tool in the manufacture of the required roll profile. This will allow the metal bristle of the brush to exclude “cutting off” profile irregularities during longitudinal movement, and also, “copying” the feed step of the cutting tool, to be in constant contact with its depressions.

The essence of the proposed method for processing rolls is illustrated in the drawing, which shows a device for processing rolls that implements the proposed method.

The method of processing rolling rolls is carried out as follows.

Previously, the surface of the rolling roll 1 (Fig.) of a given diameter (D _in ) is pre-treated with a cutting tool, for example, a modular cutter, to obtain the desired profile. Next, the rolling roll 1 and the brush 2 diameter (D _w ) with a metal wire pile 3 set with the placement of their longitudinal axes in the same plane and put into contact. Roll 1 set the angular velocity n ₁ . To eliminate vertical slip brush 2 calculate and set the angular velocity n ₂ according to the proportion:

D _в – rolling roll diameter, mm;

D _sh - brush diameter, mm;

n ₁ - angular speed of the rolling roll, rpm;

n ₂ - angular speed of the brush, rpm.

To eliminate horizontal slip, the speed of mutual movement of the brush and the rolling roll is set equal to the feed rate of the cutting tool during pre-treatment for applying the profile of the rolling roll.

Further, a bar 4 made of a wear-resistant coating, for example, fluoroplast, is pressed against the metal wire pile 3 of the rotating brush 2 with a pressure that ensures the appearance of an aerosol in the contact zone. After the disappearance of the aerosol caused by the contact heating of the metal wire pile 3, sufficient for the appearance of wettability of the surface of the periphery of the metal wires of the pile 3 by the fluoroplastic particles, the brush 2 is moved along the longitudinal axis of the rolling roll 1. The fluoroplastic particles from the pile 3 of the brush 2 fill the depressions of the specified profile of the surface of the rolling roll 1 , forming a uniform fluoroplastic coating. At the same time, the quality is ensured precisely by the “laying” of the coating from the periphery of the brush pile into the hollows of the roll profile, which will ensure their completeness.

An example of the implementation of the method. A rolling roll with a diameter of 500 mm, made of 9Kh2MF steel, with a surface hardness of 90-100 HRC, was installed on a D/n 500 roll grinder. Roll rotation speed 20 rpm. The roll was pre-treated with a 0.5 mm modular cutter with a longitudinal feed of the machine support of 5 mm/min to give the surface of the roll an involute profile. Received a uniform roughness. After that, a brush with a diameter of 200 mm was chosen. The angular speed of rotation of the brush was set according to the proportion (1), where: n ₂ \u003d (D _in / D _w ) _* n ₁ \u003d (500:200) _* 20 \u003d 50 (rpm). The longitudinal feed speed of the brush was set equal to the longitudinal feed speed of the modular cutter, i.e. 5mm/min. Then bar 4 made of PTFE-4 was placed on top of the brush in a vertical guide tube. The weight of the bar provided the necessary feed pressure. The longitudinal feed of the brush began after the cessation of the aerosol cloud in the contact zone of the pile 3 of the brush 2 with the surface of the PTFE bar. Particles of PTFE metal wire pile 3 of the brush 2 were transferred from the bar 4 into the depressions of the involute profile of the rolling roll, forming a PTFE coating. The surface of the rolling roll after application had a mirror appearance - the irregularities of the profile were filled with the coating material.

The area of the fluoroplastic coating on the surface of the roll was more than 70%, due to a significant reduction in friction in the sliding zone, the service life of the roll increased by 1.5 times, and the average amplitude of the surface roughness of the roll decreased by 2 times.

Claims (1)

A method for processing rolls, including pre-treatment of the roll with a cutting tool by feeding it longitudinally, placing the roll and brush in contact with their longitudinal axes in the same plane, bringing the periphery of the brush into contact with a bar made of wear-resistant material in a state of mutual wetting at the point of contact, coating the rolling roll by rotating the brush and the rolling roll and their mutual movement along the longitudinal axis, characterized in that after pre-treatment of the rolling roll, the angular velocities of the rolling roll and the brush are set so that their linear velocities at the place of their contact were equal, while the speed of mutual movement of the rolling roll and brush along the longitudinal axis is set equal to the speed of the longitudinal feed of the cutting tool.

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