Application of Cold Spray Zinc Coating and Coating Thickness Detection

The bridge is in a natural environment that spans rivers, lakes and seas. It is exposed to wind and rain, humidity and pollution for a long time. It is subject to dynamic and static loads for a long time. It is vulnerable to corrosion damage.

1. Cold spray zinc coating used in bridge steel structure

In order to ensure the safe operation of the bridge, the steel structure system of the bridge needs to be protected against corrosion. At present, more applications are used to protect steel structures from corrosion by hot-dip galvanizing, hot-dip galvanizing and multi-layer coatings. In recent years, the development and application of cold sprayed zinc has also provided new anticorrosion technology and materials for the practical long-term protection system of bridge steel structures.

Due to the importance of the steel structure and the difficulty of subsequent maintenance, it has always been preferred to use protective technologies such as heavy-duty anticorrosive coatings with excellent performance and special coating and sealing. Various advanced anti-corrosion new technologies, new processes and new materials have better market prospects and investment benefits in the protection of steel structures of bridges. Because the construction method of cold spray zinc coating is simple, flexible and convenient, cold spray zinc coating can be widely used for corrosion protection and maintenance of various bridge steel structures.

2. Thickness detection of anticorrosive coatings for bridge steel structures

In addition, the detection of the anticorrosive coating thickness of the bridge steel structure is also extremely important. According to statistics, 75% of the reason is that the substrate is damaged due to the damage of the anticorrosive coating. So when a section of anti-corrosion project is completed, we will use a coating thickness gauge to check its coating thickness. For different anticorrosive materials and different anticorrosive environments, the thickness requirements of the anticorrosive coating are different. According to the specific corrosion environment and requirements, it is mainly divided into the following five types:
       (1) Corrosive environment with low degree of corrosion: the thickness of low-quality anticorrosive coating is more than 80μm, the thickness of medium-quality anticorrosive coating is more than 150μm. The thickness of high-quality anticorrosive coating is more than 200μm.
       (2) Medium-level corrosion environment: the thickness of low-quality anticorrosive coating is more than 120μm, the thickness of medium-quality anticorrosive coating is more than 160μm. The thickness of high-quality anticorrosive coating is more than 200μm.
       (3) Corrosive environment with high corrosion: The thickness of low-quality anticorrosive coating is more than 160μm, the thickness of medium-quality anticorrosive coating is more than 200μm. The thickness of high-quality anticorrosive coating is more than 240μm.
       (4) Industrial corrosive environment (higher degree of corrosion): The minimum thickness of anticorrosive coating is 200μm.
       (5) Marine corrosive environment (ultra-high degree of corrosion): The thickness of medium-quality anticorrosive coating is more than 280μm. The thickness of high-quality anticorrosive coating is more than 320μm.
       For the measurement of anti-corrosion coating thickness, Linshang Technology LS223 coating thickness gauge is recommended. This coating thickness gauge uses the principle of eddy current and Hall effect to accurately measure the non-magnetic coating thickness on magnetic metals and non-conductive coating thickness on non-magnetic metal substrates. LS223 coating thickness gauge can be widely used in the shipbuilding industry, hardware, metal processing industry coatings and anti-corrosion coating thickness measurement. The LS223 coating thickness gauge adopts the separate  design and can view the data while measuring in a complex environment. The coating thickness gauge can accurately and non-destructively measure the coating thickness, which can be used in engineering sites and laboratories.