The structure of the slender hammering stem with elastic supporting device isdesigned in this paper,a multiple degree of freedom vibration dynamic model is set up.

This paper analyzes the factors which influence the life of the hammer rod and proposes the improving methods.

Early and continuous fatigue failure of 16 t heavy-duty drop hammer rods happened in forging transmission pan,and fracture reasons were analyzed by means of chemical compositions analysis,surface abrasion test and macro fracture analysis,hardness measurement,metallographic examination,and combining with forging technical process.