Views: 146 Author: Site Editor Publish Time: 2020-06-23 Origin: Site
As we all know, everyone knows that the galvanizing of caster wheel is actually a layer of zinc on the surface of the caster wheel alloy. It is mainly a surface treatment technology that plays a role in appearance and anti-rust. However, there are many methods for galvanizing caster wheel, and various galvanizing methods are used in different places. The following Ningbo Central Metal Products Co., Ltd. will introduce you to several methods of galvanizing caster wheel.
1. Cyanide zinc plating
Since cyano group (CN) is highly toxic, environmental protection puts forward strict restrictions on the use of cyanide in electroplating zinc on caster wheel hardware parts, and continuously promotes the development of electroplating zinc plating solution systems that reduce cyanide and replace cyanide caster wheel hardware parts. It is required to use low cyanide (micro-cyanide) caster wheel hardware plating solution. The product quality of the caster wheel hardware part after this process is good, especially after the color plating is passivated, the color can be well maintained.
2. Zincate zinc plating
The zincate zinc plating process is evolved from cyanide zinc plating. At present, two major factions in China are:
(1) "DPE" series of Wuhan Material Insurance Institute.
(2) "DE" series of radio and television stations.
Both of them belong to zincate zinc plating of alkaline additives; PH value is 12.5~13. The lattice structure of the plating layer adopting this process is column-shaped, has good corrosion resistance, and is suitable for color galvanizing.
Typical formula: NaOH-110~120g/l; ZnO--11~12g/l; 94--5~7g/l. 94 is the combination of product code "DPE-Ⅱ" and ethanolamine.
Note: After the product comes out of the tank -> water washing -> light (nitric acid + hydrochloric acid) -> water washing -> passivation -> water washing -> water washing -> ironing -> drying -> aging treatment (80 ~ 90oC in the oven).
3. Chloride zinc plating
Chloride zinc plating process is widely used in the electroplating industry of caster wheel and hardware, accounting for up to 40%. After passivation (blue white) can be replaced by chromium zinc (comparable with chrome plating), especially after adding water-soluble varnish, it is difficult for laymen to distinguish whether it is galvanized or chromium-plated. This process is suitable for white passivation (blue white, silver white). When the customer has no special requirements, it is best to choose silver-white passivation (color remains stable).
Typical formula: KCl--180~220g/l; ZnCl--65~75g/l; H3BO3--25~30g/l (buffer); PH value 5~5.5; CI-87--15~20g/ l (brightener).
4. Sulfate zinc plating
The sulfate zinc plating process is suitable for continuous plating (wires, strips, simple, large and large parts, parts) with low cost.
Typical formula: ZnSO4--300~500g/l; H3BO3--25~30g/l; PH value: 4.5~5.5; sulfur zinc--15~20g/l (brightener). copyright by:www.caster wheelcn.com
In summary, the effects of various galvanizing methods in various fields are also different. Therefore, when choosing caster wheel, the galvanizing method of caster wheel should be selected according to the different environments of use.