Abstract: A number of hot-rolled rotary of some model number cracked in batch during spinning,the physical-chemical failure analysis for cracking hot-rolled rotary and technological process check were carried through to find the cause of cracking .It was caused by defects which were occurred during forging,the defect led to cracking during spring .In order to avoid the problem once more,technological measures were adopted to direct against defects during forging ,cracking was not occurred in following hot-rolled rotary producting.