| abstract |
A method is provided for producing a punch for use in a mill for drilling by rolling to manufacture seamless steel pipes and pipes, and the method for producing the punch for drilling by rolling comprises blasting a surface of the punch, spraying an arc. spray wire in order to form a film on a surface of a metal base of the punch to which the shot blasting was applied. In the passage of arc spraying, arc spraying is performed by using, as a spraying wire, a hard core wire whose iron tube-sheath is loaded with at least iron oxide particles between iron particles and the iron oxide particles (one or more FeO particles, Fe3O4 particles, and Fe2O3 particles), in order to form the film containing iron oxide and Fe. Accordingly, it is possible to improve the production efficiency of the punch, and produce the punch for drilling by rolling that can ensure the stable improvement of the life of the punch during drilling by rolling. |