1, broken belt (1) insufficient conveyor belt tension (2) conveyor belt extended use, serious aging. (3) large blocks or iron rush hit conveyor belt or stick. (4) quality of belt joints do not meet the requirements. (5) the conveyor belt connector severely deformed or damaged. (6) the conveying belt deviation is stuck (7) belt tensioning device acting on the conveyor belt tension is too large. 2, belt breakage prevention and treatment (1) change to meet the requirements of the conveyor belt. (2) should be replaced due the conveyor belt (3) strict control of bulk materials on the iron of the conveyor (4) replacement of damaged joints. (5) increase offset idler and preventive protection; conveying belt deviation found choked on rack should be immediately shut down. (6) to adjust tension of tensioning device is appropriate.