Automatic control method for concentration of leveling liquid

Abstract

The invention relates to the technical field of strip steel continuous heat treatment, and discloses a leveling liquid concentration automatic control method, which comprises a leveling liquid system, the leveling liquid system comprises a leveling liquid stock solution tank, a leveling liquid mixing tank, a leveling liquid stock solution pump, a leveling liquid stock solution flow meter, a desalted water electromagnetic valve, a desalted water flow meter, a stirring pump and a leveling liquid concentration controller, a stirrer, an on-line leveling liquid conductivity meter and a liquid level meter are arranged in the leveling liquid mixing tank, leveling liquids with different concentrations are prepared in a laboratory by using a leveling liquid stock solution and desalted water used by the unit, the conductivity of the leveling liquids with different concentrations is measured, and automatic control is performed according to the conductivity; the device can realize automatic control of the concentration of the leveling liquid without a leveling liquid concentration detector, does not depend on manual sampling and sample sending to measure the chloride ion concentration of the leveling liquid, realizes automatic detection of the chloride ion concentration and automatic adjustment of the chloride ion concentration exceeding the standard, realizes online recycling of the leveling liquid, reduces consumption of the leveling liquid and desalted water, and reduces the production cost. And the leveling liquid concentration control and chloride ion concentration standard exceeding control are unmanned.

Description

technical field [0001] The invention relates to the technical field of continuous heat treatment of strip steel, in particular to an automatic control method for leveling liquid concentration. Background technique [0002] In order to improve the shape of the strip, adjust the mechanical properties or eliminate the yield platform and obtain a suitable surface roughness of the strip, the continuous annealing or hot-dip galvanizing unit must use a leveler to level the strip. It is customary to use leveling fluid when leveling. For the continuous annealing unit, the leveling liquid can be used for lubrication and cooling, while for the hot-dip galvanizing line, the use of the leveling liquid can eliminate the zinc sticking roll marks and improve the surface quality of the strip. For example, Chinese patent CN200710023703.6 discloses an anti-macular, environment-friendly wet leveling solution, which contains 5-35% of organic acid, 5-35% of organic amine, 2-20% of corrosion inhi...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent CN201611105868.3 discloses a step-by-step concentration dosing system and dosing method, which creatively uses two dosing tanks to switch between the commissioning mode and the dosing mode, which is specially used for dosing in non-commissioning dosing tanks , so that the control accuracy of the leveling liquid concentration can be improved, but this method also uses the leveling liquid concentration detector for concentration control

Like the above-mentioned patents, our company has been unable to purchase reliable leveling liquid concentration detectors on the market, resulting in the automation of existing units that cannot be implemented using similar methods

[0006] In addition, in the traditional continuous annealing unit and hot-dip galvanizing unit, the leveling liquid is not recycled, but is discharged to the sewage treatment unit for sewage treatment after one use, resulting in a large consumption of leveling liquid and desalinated water, and high sewage treatment costs

In addition, when the chloride ion concentration of the leveling liquid exceeds the standard, the strip will be easily corroded. The existing control of the use of the leveling liquid also relies on manual sampling and delivery to detect the concentration of chloride ions, which cannot be automated.

In addition, the bacteria and mold content in each tank of the leveling liquid exceeds the standard, and the bacteria and mold gather together, which will cause problems such as clogging of the leveling liquid nozzle. It also relies on manual visual inspection and judgment, and cannot realize unmanned

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