In order to obtain excellent surface quality, the surface defects of the cast aluminum heating plate must be cleaned. At present, although there are many methods for cleaning the surface defects of cast aluminum heating plates, the main methods used are flame cleaning, air shovel cleaning, manual grinding wheels, automatic grinding wheels and belt cleaning, and turning cleaning. The following details the cleaning of the surface defects of the lower cast aluminum heating plate.
(l) Flame cleaning. The equipment is simple, efficient and very economical. It is mainly suitable for cleaning the surface defects of cast aluminum heating plates with carbon content less than 0.4%. This is because when the cast aluminum heating plate is cleaned by flame, the cast aluminum heating plate is heated locally, so thermal stress will be generated. For cast aluminum heaters with high carbon content, after the cast aluminum heating plate is cleaned or even placed for a period of time, thermal cracks may occur, which affects the quality of the cast aluminum heating plate, and may cause the cast aluminum heating plate to be scrapped. .
(2) Air shovel cleaning. The equipment is simple, but the labor intensity is high and the efficiency is low. It is not restricted by the steel type. It is suitable for cleaning local defects on the surface of cast aluminum heater.
(3) Manual grinding wheel and automatic grinding wheel cleaning. Mainly used for cast aluminum heaters that are not suitable for flame cleaning. The manual grinding wheel equipment is simple, the investment is low, the operation is flexible, but the labor intensity is high; the automatic grinding wheel cleaning efficiency is high, and more are currently used.
(4) Cleaning by turning or sanding belt or grinding wheel. This method of integral grinding for cleaning the surface defects of cast aluminum heaters is suitable for cleaning the surface defects of cast aluminum heaters of all steel grades, but it has low efficiency, high metal consumption and high cost. It is mainly used for added value and quality requirements. High cast aluminum heater (such as stainless billet) surface defect cleaning. It should be pointed out that the turning method is generally not used to remove the surface defects of the continuous casting round cast aluminum heater, because this may turn off the fine grain area of the outer surface layer of the continuous casting round cast aluminum heater, resulting in coarse columnar crystals. When exposed to the outside, the cast aluminum heater is likely to cause the perforated capillary tube to be folded out when it is perforated.