Cold rolling process capable of preventing broken edge wave defect of ultrathin steel strip

Abstract

The invention provides a cold rolling process capable of preventing a broken edge wave defect of an ultrathin steel strip. The process comprises the steps of a) setting the temperature of emulsion for lubricating a rolling unit to be 55 to 58 DEG C, setting the concentration to be 2.5 to 4.0%, and setting saponification value to be 160 to 180mgKOH / g; b) setting the chamfering width of a small head side of a medium roller body to be 50 to 55mm, setting the chamfering radian to be R2000 to R2100mm, setting the chamfering depth to be 0.8 to 1.1mm, rolling more than three volumes of boards being more than 0.25mm in thickness through a new arranged working roller, and then producing the steel strip being less than 0.25mm in thickness. According to the process, the temperature of the emulsion is increased, the molecular thermodynamic movement of rolling oil is increased and clean emulsion in a rolling seam is absorbed, so that the technical lubricating effect under extreme pressing can be improved, the frictional conditions in the roller seam can be improved, the rolling force per pass can be obviously reduced, and as a result, the broken edge wave defect can be prevented; the roller mechanism is optimized to ensure the uniform pressure of a chamfering contact area of the medium roller and the working roller, and therefore, harmful contact stress can be reduced, the thermal crown of the roller can be improved, the flatting capacity of two ends of the roller can be decreased, and the trend of broken edge wave can be prevented.

Description

technical field

[0001] The invention relates to the technical field of steel rolling, in particular to an ultra-thin strip steel cold rolling process. Background technique

[0002] At present, many steel enterprises, especially small and medium-sized private steel enterprises equipped with six-high single-stand cold rolling mills, are producing extremely thin cold-rolled strip steel with a thickness of 0.25 mm or less. When producing the above-mentioned thin-gauge products, due to the large total reduction rate (generally 88-92%), the work hardening of the finished product pass is significant, resulting in a large rolling force, especially in the stage of slowing down and tailing, and the negative crown of the roll is sharp. increase, resulting in a large amount of thinning at the edge of the steel plate, which is manifested as severe edge-breaking waves (also known as micro-double-sided waves) of the off-line strip steel. This defect is not easy to monitor online, and it c...

Examples

Embodiment Construction

[0013] The present invention will be further described below.

[0014] The cold-rolling process for preventing the chipped edge defect of the ultra-thin strip includes the following steps:

[0015] a) Set the temperature of the emulsion lubricated by the rolling mill to 55-58°C, the concentration to 2.5-4.0%, and the saponification value to 160-180mgKOH / g. Increase the temperature of the emulsion from 50-55°C to 55-58°C, the aggravation of the thermal movement of the rolling oil molecules and the clean emulsion sucked into the roll gap can increase the process lubrication effect at the limit pressure and improve the internal friction conditions of the roll gap , significantly reduce the rolling force of the pass; the appropriate increase in the temperature of the emulsion can reduce the cooling effect on the roll gap, increase the thermal crown of the roll, reduce the amount of flattening at both ends of the roll, reduce edge thinning, and prevent edge chipping wave defects. ...

technical field

[0001] The invention relates to the technical field of steel rolling, in particular to an ultra-thin strip steel cold rolling process. Background technique

[0002] At present, many steel enterprises, especially small and medium-sized private steel enterprises equipped with six-high single-stand cold rolling mills, are producing extremely thin cold-rolled strip steel with a thickness of 0.25 mm or less. When producing the above-mentioned thin-gauge products, due to the large total reduction rate (generally 88-92%), the work hardening of the finished product pass is significant, resulting in a large rolling force, especially in the stage of slowing down and tailing, and the negative crown of the roll is sharp. increase, resulting in a large amount of thinning at the edge of the steel plate, which is manifested as severe edge-breaking waves (also known as micro-double-sided waves) of the off-line strip steel. This defect is not easy to monitor online, and it c...

Examples

Embodiment Construction

[0013] The present invention will be further described below.

[0014] The cold-rolling process for preventing the chipped edge defect of the ultra-thin strip includes the following steps:

[0015] a) Set the temperature of the emulsion lubricated by the rolling mill to 55-58°C, the concentration to 2.5-4.0%, and the saponification value to 160-180mgKOH / g. Increase the temperature of the emulsion from 50-55°C to 55-58°C, the aggravation of the thermal movement of the rolling oil molecules and the clean emulsion sucked into the roll gap can increase the process lubrication effect at the limit pressure and improve the internal friction conditions of the roll gap , significantly reduce the rolling force of the pass; the appropriate increase in the temperature of the emulsion can reduce the cooling effect on the roll gap, increase the thermal crown of the roll, reduce the amount of flattening at both ends of the roll, reduce edge thinning, and prevent edge chipping wave defects. ...

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