Hot galvanizing process

Abstract

The invention discloses a hot galvanizing process. The hot galvanizing process is characterized in that thiourea with concentration being 0.12% is added during pickling, wherein a picking temperature is 50 DEG C, so that a workpiece can be prevented from being over-etched, and hydrogen absorption capacity of ferro matrix can be reduced; an ultrasonic cleaning agent with concentration being 7.5% is added during ultrasonic cleaning, so that greasy dirt and corrosion on the surface of a workpiece can be quickly removed; the ultrasonic cleaning agent is trichloro ethylene which does not contain phosphate, is harmless to aquatic life, is harmless to a human body and is free of stimulation on skin; the cooling comprises the following two steps: a first step, slow cooling, wherein a cooling speed is 10 DEG C / S, and the workpiece is cooled to a temperature of 650 DEG C; and a second step, quick cooling, wherein the workpiece is cooled by a cooling fan, and is cooled to a temperature of 445 DEG C, so that the structure of the workpiece can be prevented from being damaged; pure aluminum with concentration being 0.02% is added into a zinc pot before galvanizing, so that mobility, at a relatively low temperature, of a hot galvanizing solution is improved, a coating is prevented from being thickened, and the appearance of the coating is improved; a bearing produced by adopting the method has the advantages of corrosion resistance, great bonding strength of a galvanized coating and long usage time, is great in market potential and is wide in prospect.

Description

technical field [0001] The invention belongs to the field of machinery, and more specifically, the invention relates to a hot-dip galvanizing process. Background technique [0002] Galvanizing is a very effective method for metal anti-induction, and hot-dip galvanizing is the fastest-growing galvanizing technology in the world today. With the continuous progress of hot-dip galvanizing technology, hot-dip galvanized metal products are widely used. At present It has covered many aspects such as construction, automobiles, light industry, home appliance packaging, agriculture, animal husbandry and fishery. But existing hot-dip galvanizing process has a lot of places to need improvement, and for example patent number is: CN104561876A has announced a kind of hot-dip galvanizing process method, and it comprises the steps: (1) pre-plating inspection; (2) pendant; (3) (4) acid rust removal; (5) washing; (6) surface cleanliness inspection; (7) fluxing; (8) hot-dip galvanizing; (9) wa...

AI Technical Summary

Problems solved by technology

But existing hot-dip galvanizing process has a lot of places to need improvement, and for example patent number is: CN104561876A has announced a kind of hot-dip galvanizing process method, and it comprises the steps: (1) pre-plating inspection; (2) pendant; (3) (4) acid rust removal; (5) washing; (6) surface cleanliness inspection; (7) fluxing; (8) hot-dip galvanizing; (9) water cooling; (10) zinc layer thickness inspection; (11) ) passivation; (12) unloading; (13) grinding, refurbishment and final inspection; although there are many pretreatment steps, the treatment of the metal surface is not complete. Zinc method, the invention uses side heating for the galvanizing pot, which can conveniently control the temperature of the zinc liquid and accelerate the precipitation of zinc slag, thereby reducing the amount of zinc taken away by the plated parts; The salt content reduces the amount of zinc slag in the zinc pot; at the same time, the output per hour is controlled to stabilize heat loss and reduce zinc consumption due to temperature fluctuations. Lack of pre-treatment such as preheating and annealing of galvanized workpieces, Will directly affect the performance and quality of galvanized workpieces