Control method for keeping insertion position of dummy bar

Abstract

The invention discloses a control method for keeping the insertion position of a dummy bar. By exciting the pre-excitation effect of an inverter of a motor of a driving roller of a withdrawal and straightening unit, the control method utilizes the zero-speed electromagnetic braking torque provided for the motor by the closed-loop speed control inverter after pre-excitation to counteract the opposite drag force applied on the driving roller of the withdrawal and straightening unit by the gravitational effect of the dummy bar, so that the dummy bar can be kept in a zero-speed still state at the insertion position, and at the same time, an encoder is utilized to monitor and judge the actual torque of the motor in real time, playing a role in remotely monitoring the braking state and giving the alarm for abnormalities.

Description

technical field [0001] The present invention relates to continuous casting control technology, more specifically, relates to a dummy bar insertion position maintenance control method. Background technique [0002] The dummy rod is a multi-section flexible steel rod, which is used to pull and guide the primary billet shell in the crystallizer, and move toward the direction of billet discharge. Before each casting (CAST) start of the continuous casting machine, the dummy bar preparation operation before the continuous casting start is carried out, including dummy bar insertion, dummy bar retention and dummy head sealing. For the continuous casting machine that adopts the bottom-mounted dummy bar delivery, it is necessary to transport the dummy bar from the storage position on the roller table from bottom to top and insert it into the lower opening of the crystallizer, and then the operator jogs and fine-tunes the position of the dummy bar. position until the head of the dummy...

AI Technical Summary

Problems solved by technology

[0007] The position of the dummy bar after it is inserted into the crystallizer is completely dependent on the mechanical braking force of the motor brake, the reliability is not high, and the risk of the dummy bar falling down is relatively high

Since the brake pads are easy-to-wear parts, and the on-site environmental conditions are poor (high temperature, dust), with the operation and use of the equipment, faults such as the brake pads and mechanisms are unavoidable, and once the brake failure or performance Deterioration will directly affect the braking force of the driving roller of the tension leveling machine, resulting in the consequence of the dummy bar falling

[0008] The holding brake is installed in the drive roller motor of the tension leveling machine, which cannot be monitored online, and the equipment status is difficult to guarantee

Since the brake is installed at the rear of the driving roller motor of the on-site tensioning and leveling machine, it is difficult for personnel to access it, and the online inspection and disassembly are extremely inconvenient. Therefore, it is difficult to check and grasp the equipment status at ordinary times, and it is also difficult to carry out targeted maintenance

The motors with brakes installed on the tension leveling machine are all imported brands, the price is relatively expensive, and the installed capacity on site is relatively large. If they are frequently replaced in order to maintain the equipment status, the maintenance cost of the equipment will increase significantly

If the after-event maintenance mode is adopted, the problem of dummy rod sliding will be dealt with firstly. Firstly, the downtime for maintenance will cause production interruption and disrupt the rhythm of production logistics. Secondly, it will cause great hidden dangers and risks of steel breakout accidents.

[0009] To sum up, the existing method of maintaining the insertion position of the dummy rod only by the mechanical braking force of the brake has the disadvantage that the state of the brake is difficult to monitor and control, and it is easy to cause the dummy rod to slide down and cause the pouring to break. The risk of breakout and steel breakout is high, and it is easy to cause unplanned downtime, which is not conducive to the stable and smooth production

Images