The cause of shrink holes in the coating coating process

China Paint Online News Information: The cause of shrinking holes in the coating spraying process is the cause of the coating itself; Reasons for the coating line coating process. So what are the two reasons for the above two reasons in the coating spraying process? Small disaster here to introduce you. There are several reasons for the coating itself.In the process of manufacturing coatings, the amount of leveling agents, desuming agents and other additives is not enough or uneven dispersion, resulting in some coatings sprayed to the surface of the work piece of powder material does not contain leveling agents or desiccants; Because the coating equipment is not clean, resulting in uneven deployment in the process of paint production or impurity pollution; The use of compressed air oil and moisture removal is not complete, water, oil into the coating spray, will also make the coating shrink hole.coating coating line coating process reasons: the surface treatment of the coating is not clean, when the oil removal process before coating is not clean, on the surface rough or pinhole on the coating left oil, phosphate oil is still residual on the coating, the formation of the coating easy to produce shrink holes, so the pre-treatment must be treated cleanly and thoroughly.coating spray coating surface is uneven, holding is cast iron, aluminum and hot-tie steel plate, such as the surface of the coating is uneven, there are pores, in the coating process, the paint melting flow usually, the air in the pores by heat expansion will bulge the coating film is curing, if the coating film can not be leveled will form a shrink hole. Solution: the coating will be preheated and then coated to avoid the phenomenon of air expansion top coating film; Add a deblister to the coating, which reduces surface pressure during melting leveling, allows air in the applied pores to escape in time, and allows the coating film to heal quickly.When changing paint spray coating varieties, equipment cleaning is not thorough, resulting in mixed old and new coatings, mutual interference, easy to make the coating to produce shrink holes, so in the replacement of paint varieties, be sure to spray guns, powder tanks, powder pipes, powder room and other equipment clean.After the surface treatment of the surface of the coating residual water, there is residual moisture in the coating after baking moisture volatility will make the coating film shrink hole, so in the surface treatment to adjust the drying temperature and time after washing, so that the air in the coating pores escape in time and the coating film quickly healed.we must pay attention to the cleaning of the machine in the coating spraying operation. Here the editor-in-chief introduced so much, I hope to help you.