Abstract: The production cases were applied to analyze the performance parameters variation and the effects caused by the coal shearer drum and pick abrasion. The instant load variation under the overload or impact load would affect to the rigid and stability of the coal shearer and to the micro features of the driving system abr asion.The analysis results showed that under the pick failure conditions,the coal cutting and coal loading capacity of the coal shearer would be reduced.The instant loa d increased remarkably,the abrasion of the coal cutting unit and driving system of the haulage mechanism would be enhanced and thus chain failures of the working me chanism would be occurred. According to the hidden dangers ,some related improved measures and proposals were proved.