HGM series threering medium speed Perlite powder grinding mill is designed and manufactured by shanghai clirik machinery, is the new type grinding equipment specializing in producing fine and superfine powder of noninflammable, nonexplosive and brittle materials with Mohs' hardness under six, such as calcite, chalk, limestone, dolomite, kaolin, bentonite, talc, mica, magnesite, illite ...