Can a rust-primer be used for the surface of metal after treatment?

I understand the poster’s question now; it’s about whether it’s possible to apply an anti-rust primer to the surface of petrochemical equipment that already has rust and flaking paint, right? Here are a few points for reference: A rust-primer does not completely eliminate the need for rust removal; it is more suitable for surfaces with light rust that adheres well. In cases like those shown in the image, where large areas of paint have peeled off and rust is quite visible, it is recommended to first sand and remove the loose old paint and loose rust before applying the primer ； Petrochemical equipment is typically subject to strict requirements in terms of oil resistance and weather resistance. When choosing a primer with rust-resistant properties, it is also important to ensure compatibility with the topcoat that will be applied later; it is best to select a coating system in accordance with the relevant standards for corrosion protection of petrochemical equipment ； For equipment that already shows signs of significant rust, it is best to consult professional anti-corrosion specialists first, and to develop a comprehensive anti-corrosion plan based on the actual operating conditions of the equipment, in order to avoid issues related to reduced anti-corrosion effectiveness in the future.

If the device is to achieve \"long-term maintenance-free\" operation, it cannot rely solely on a rust-prone primer.