IMPROVING THE WEAR PROTECTION ON THE GRIN DING ROLLERS IN ROLLER GRINDING MILLS

Considerable wear takes place at the lining and grinding elements duri ng grinding in roller grinding mills. In the past the grinding parts w ere normally made from cast steel. Developments in the last 15 years h ave moved increasingly towards producing the wearing parts for the gri nding elements from chilled cast iron. Worn-out wearing parts have had to be scrapped The new regeneration technology, i. e. build-up weldin g of worn wearing parts in the roller grinding mills, came from Americ a. Core wires containing high levels of chromium and carbon form the m ain build-up welding materiaL Build-up welding has been used successfu lly to produce armouring up to 150 mm thick although the worn wearing parts are made of materials designated in the literature as not weldab le. Quality assurance is particularly important because of the difficu lties caused by the materials when carrying out the build-up welding. Wearing parts with carefully applied armouring can now achieve service lives in roller grinding mills which are two to three times higher th an those of unarmoured grinding parts.