Solvent method batch hot-dip galvanizing water-cooling chromium-free passivating agent and its preparation and use method

Abstract

The invention discloses a chromium-free passivating agent for solvent-method large-scale hot galvanizing water cooling and preparing and using methods thereof, and belongs to the field of solvent-method large-scale hot galvanizing. The chromium-free passivating agent for solvent-method large-scale hot galvanizing water cooling comprises 1%-10% of a film forming agent, 0.5%-5% of an accelerant, 0.1%-1% of a chelating agent, 0.2%-2.5% of a hole sealing agent, 0.1%-0.4% of a wetting agent and the balance water. The preparing method of the chromium-free passivating agent for solvent-method large-scale hot galvanizing water cooling comprises the steps that the film forming agent and the accelerant are added into water, stirring is conducted, the chelating agent and the hole sealing agent are added, stirring is conducted, the wetting agent is added, and the materials are stirred to be uniform. The using method of the chromium-free passivating agent for solvent-method large-scale hot galvanizing water cooling comprises the steps that the chromium-free passivating agent is added into a water cooling tank, stirring is conducted, a galvanized workpiece is immersed into water cooling liquid to be subjected to passivating treatment and then lifted out and drained off. When the galvanized workpiece is treated by adopting the method, a good passivating effect is achieved, the galvanized workpiece has the original color and luster, the product quality meets the industrial production standards, and the corrosion resistance is good. The chromium-free passivating agent is poisonless and harmless, low in cost and easy and convenient to operate and has the high industrial popularization value.

Description

technical field [0001] The invention relates to the field of batch hot-dip galvanizing by solvent method, in particular to a chromium-free passivator for water cooling of batch hot-dip galvanizing by solvent method and its preparation and use method. Background technique [0002] Solvent method batch hot-dip galvanizing products are widely used in guardrails in the fields of electric power, construction, transportation, communication, etc., welded steel structures, light poles, plumbing equipment, line fittings, iron tower components, etc. Due to the high temperature and high humidity of the water cooling process and the high salt spray atmosphere in the coastal areas, the solvent method batch hot-dip galvanizing enterprises all adopt hexavalent chromium passivation (adding 0.2% to 0.3% chromic anhydride in the water cooling tank) to prevent the production process of workpieces. rust. This passivation method will produce a large amount of chromic acid mist and chromium-cont...

AI Technical Summary

Problems solved by technology

This passivation method will produce a large amount of chromic acid mist and chromium-containing wastewater, which will seriously endanger the health of workers, and will also pollute the environment, causing huge harm

Due to the particularity of the working conditions of the water-cooling process (requiring high-temperature stability of the passivation solution, no corrosion to the workpiece, high tolerance of the passivation solution to zinc ions, etc.), related research has hardly been reported.