Covering agent (perlite): covering agent is acidic volcano rock formed by rapid cooling of the vitreous rocks after special processing, sprinkled on freshly baked steel (iron) water layer, the rapid expansion of Volume 4 to 30 times, with slag, insulation and other characteristics, it is commonly known as the slag removing agent. It has opened up a new field of perlite application in foundry production. The application in foundry production has the following advantages: 1, good insulation properties, in general can reduce the cooling rate of hot metal from 20% to 30%. 2, slag collection performance is good, easy to slag skimming, beneficial to molten iron purification. 3, help the ball stabilization, improve spheroidization effect weakened magnesium. 4, reduce environmental pollution, improve labor conditions. 5, the economic effect is good, the transmission cost can be reduced by 30%.
Methods: to use steel or iron out the full package, the slag ladle covering agent sprinkled on the surface to remove surface scum, sprinkle a layer, no longer can stir the insulation casting. The ladle is poured out every time after pouring, and the effect is better. Especially the treatment of ductile iron with the best effect. The general dosage is 0.1--0.15%.
Main chemical components: (%)
SiO AL2O3 FeO Na2O MgO K2O CaO other elements
60-80 20-30 2-2.3 0.6-1.0 0.8-0.9 3-3.5 0.5-1.2 0.5-2.0