CONCLUSIONSTo improve the properties of magnesite patching powders, it is advisable to treat with from 1.5 to 3.5% of mineral oils, because the oil-treated powders have a number of advantages in comparison with dry powders of the same grain-size composition: enhanced compactibility, improving the quality of the patching layer; reduced dust content, improving the working conditions during loading, transport, ~ and furnace patching; absence of caking during storage; the sinterability is no worse than that of ordinary patching powders, because the combustion of the oil is complete,