Can expired casting waterborne coatings be used? What defects will appear after use?

Expired casting coatings must not be used. I am also Baoding Xinghe Foundry Co., Ltd., operating a steel casting plant. I've been troubled by this before. At present, most coatings will fail before the shelf life, and the suspension and strength will decrease, so that there will be traces after the coating is used. When it's dry, a layer will fall off when you touch it with your hands, just like it's not painted. Casting will wash away all the coatings on the surface, leaving impurities on the surface of the casting. I changed it several times, but the cost of using Shi Tian in Jining was too high, and then it was useless. I contacted Botou, Hebei, and used it again. The quality is much worse than that of Shi Tian. Later, a casting engineer brought me a Beijing Huaqiang casting coating to try. The price is not too high, but the effect is very good. I think it suits us. I heard that the paint was developed by the Foundry Association on behalf of Liu Huaqiang, and I applied for a patent. Anyway, I think it is quite economical. No matter who made it, at least we can produce finished products without affecting the quality of castings. Here it is. Yes!