METHOD FOR SEAMLESS UPSETTING OF INSERTION BOLTS FOR RAILWAY FASTENINGS Russian patent published in 1997 - IPC

FIELD: seamless upsetting of bolts in automated upsetting machine. SUBSTANCE: method involves preliminary and final forming of head. At the first position head is formed by complete intaking of metal and square neck is preformed. At three subsequent final forming positions, rectangular head is gradually formed, with length of rectangle being increased and width decreased. Method further involves forming supporting spherical surface of head; providing square faces of neck by gradual upsetting; reducing rod for thread knurling and forming facet. EFFECT: increased efficiency, simplified method and improved quality of bolts. 1 dwg