Chocolate Processing Machinery - PT. Garda Mandiri TeknikIn the cocoa and chocolate industry Royal Duyvis Wiener' ball mills are recognised as being the best around. Global industrial demands have been ta.ball mill teknik,Read More. - PT. Garda Mandiri TeknikWith this innovative chocolate production machinery, Royal Duyvis Wiener combine: a pre mixer with ball mill refiners for superior grinding, and if required can.