SYSTEM OF EQUIPMENT FOR PIERCING AND ROLLING MANDREL PRODUCTION Russian patent published in 2016 - IPC B21B25/00 

FIELD: technological processes.

SUBSTANCE: invention relates to piercing and rolling mandrel production line used for seamless steel pipe production. Said line comprises mandrel surface blasting device, located before electric arc spraying device to perform steel wire arc spraying on main mandrel metal surface after blasting to form film on it, containing Fe oxide and Fe. Electric arc spraying device contains at least two spraying chambers, each of which is used for forming a film in each of sections in turn, on which main mandrel metal surface is divided along mandrel axial direction. In each spraying chamber there is and arc sprayer gun for steel wire melting using electric arc and fused material spraying from it on main mandrel metal surface. Electric arc spraying is performed at intersection angle between electric-arc sprayer gun spraying flow axial line and main mandrel metal surface located in the range from 35 degrees to 90 degrees. Mandrel has shape of bullet and comprises body part and tip part. First spraying chamber is made with possibility to generate film in body part area on base mandrel metal surface, and second spraying chamber is with possibility of forming a film in tip part area on base mandrel metal surface. Mandrel, on which film is formed in second spraying chamber, has film on body part, formed in first spraying chamber.

EFFECT: stable higher endurance limit of mandrel.

1 cl, 8 dwg, 1 tbl, 5 ex