When the plastic-sprayed cable tray uses different RAL color cards, there are indeed some differences in the weather resistance and adhesion of its coating, which mainly depends on the pigment composition and formula design used in the powder coating. In terms of weather resistance, dark colors (such as RAL 9005 black and RAL 7016 dark gray) contain more UV stabilizers and show better resistance to UV aging, which is particularly suitable for long-term outdoor use, but its high heat absorption rate may accelerate coating aging in high temperature environments; light colors (such as RAL 9010 white and RAL 7035 light gray) can effectively reduce heat accumulation with good sunlight reflection properties, and are more suitable for use in tropical areas, but long-term exposure may cause slight yellowing. For special colors (such as RAL 3020 red and RAL 5015 sky blue), due to the possible presence of organic dyes, their outdoor weather resistance is relatively poor, and it is recommended to be used in indoor environments first.
In terms of adhesion, the performance differences of different color coatings are relatively small. As long as the pre-treatment process (phosphating, cleaning) and curing parameters are up to standard, all colors can meet the adhesion requirements of GB/T 9286 standard 0. However, it should be noted that coatings containing metallic pigments (such as RAL 9006 aluminum gray) may affect conductivity, and high-filled dark pigments may increase the internal stress of the coating. These need to be specially considered in process design. In practical applications, epoxy resin-based powders have better chemical corrosion resistance than polyester-based powders, and the spraying effect of galvanized steel substrates is better than that of cold-rolled steel.
Color selection recommendations for different usage scenarios: RAL 7016 dark gray or RAL 9005 black are recommended for outdoor and coastal environments due to their excellent UV and salt spray resistance; RAL 9010 white or RAL 7035 light gray are suitable for high temperature environments to reduce the risk of thermal aging; RAL 9003 white or RAL 7035 light gray are suitable for clean areas to maintain a clean appearance; RAL 7032 pebble gray or RAL 7024 graphite gray are recommended for chemical and industrial areas, which can hide stains and resist chemical splashing. To ensure product quality, suppliers should be required to provide test reports such as QUV aging test (ASTM G154), salt spray test (ISO 9227) and cross-cut adhesion test (ISO 2409), and pay special attention to color stability data. The actual application case of a photovoltaic power station shows that after 10 years of use, the RAL 7016 dark gray spray-coated tray remains intact, while the RAL 3020 red tray fades significantly, which fully confirms the importance of color selection.
In summary, although the color selection will not change the basic protective performance of the spray-coated cable tray, the weather resistance and applicable environment of different colors do differ. When selecting the actual model, in addition to considering the aesthetic requirements, more attention should be paid to key factors such as powder type (epoxy/polyester), substrate quality, and process control. At the same time, the most suitable color scheme should be selected in combination with the specific use environment to ensure that the product can maintain optimal performance throughout its life cycle. It is recommended to obtain complete technical parameters and test reports from suppliers when purchasing, especially to confirm whether the selected color meets the requirements of relevant standards such as ISO 12944.
