Repairing method for supporting roller of plate and strip rolling mill

Abstract

The invention discloses a dish-shaped pit repairing method for a supporting roller of a rolling mill. The method includes the following steps that (1) an ultrasonic flaw detection mode is used for confirming the roller body crack range and depth, or the contact fatigue flaking range and depth or the collision flaw range and depth of the supporting roller of the rolling mill; (2) according to the roller body flaw position of the supporting roller of the rolling mill, a grinding machine and a polishing machine are used for conducting manual polishing treatment, a polished pit in a treated face is repaired to be in a bowl shape or in a dish shape, and due to the depth of the bowl-shaped pit or the depth of the dish-shaped pit, the purpose that flaws are eliminated or the flaws are controlled in an unstressed safe area can be achieved; (3) dye penetrant inspection is further matched in the polishing process, and it is guaranteed that the flaws can be completely polished or controlled in the unstressed safe area; (4) the position between the treated face and an adjacent plane or an adjacent curved surface is polished into a smooth transition circular arc; (5) grinding machining is conducted on a grinding machine; (6) the transition circular arc arranged between the treated face and the adjacent plane or the adjacent curved surface is treated again. The grinding amount of the supporting roller is reduced, the repairing efficiency is improved, grinding wheel consumption is reduced, and the use and maintenance cost of the supporting roller is lowered.

Description

technical field [0001] The invention relates to the use and maintenance of rolling mill back-up rolls in the metal pressure processing industry, in particular to a method for repairing the back-up rolls of a strip rolling mill. Background technique [0002] In the steel rolling production process, most of the huge rolling force of the steel plate or steel strip on the work rolls of the rolling mill is transmitted to the backup rolls, and the backup rolls also bear a large bending stress. Due to the long replacement cycle of the backup rolls, it is easy to generate stress. Concentration, fatigue hardening, rolling accidents, etc., lead to defects such as cracks, fatigue spalling or bruises on the roll surface. [0003] In the prior art, in order to prevent the above-mentioned defects from continuing to expand in subsequent use, resulting in complete failure of the backup roller, the conventional treatment method is to grind the backup roller on a grinder to completely remove ...

AI Technical Summary

Problems solved by technology

[0002] During the steel rolling production process, most of the huge rolling force of the steel plate or steel strip on the work roll of the rolling mill is transmitted to the backup roll, and the backup roll also bears a large bending stress. Due to the long replacement cycle of the backup roll, it is easy to generate stress Concentration, fatigue hardening, rolling accidents, etc., resulting in defects such as cracks, fatigue spalling or bruising on the roll surface

[0003] In the prior art, in order to prevent the above-mentioned defects from continuing to expand in the subsequent use, resulting in complete failure of the back-up roll, the conventional treatment method is to grind the back-up roll on a grinder to completely remove the defects, resulting in a substantial increase in the amount of grinding, from the normal 1 The grinding amount of ~2mm increases to 5~10mm or even more. The back-up rolls of wide-sized rolling mills are expensive, and the value per millimeter is more than tens of thousands of yuan. The loss of conventional treatment methods is huge, which greatly increases the use cost and maintenance time of the back-up rolls. It will also sharply increase the consumption of tools such as grinding wheels

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