PIERCING MILL BAR Russian patent published in 2017 - IPC B21B19/04 

FIELD: metallurgy.

SUBSTANCE: bar has a work surface including the input cone, clamp and output cone, and internal longitudinal channels for cooling. Increasing the wear resistance of the working surface of the ruler is ensured by the fact that it is provided with internal transverse channels for cooling, connecting the longitudinal channels, and the longitudinal channels are made tight. The diameter of both the longitudinal and transverse channels is 0.125…0.25 of the bar width in the cross section. On the working surface of the bar there is surfacing, deposited from heat and wear-resistant alloy of 5…8 mm thick. Width of surfacing zone B_surf is equal to the width of the bar at clamp cross-section, the length of the surfacing section at the entrance section is 0.3…0.4 of the entire length of the input cone of the bar L_in, at the output section - 0.5…0.8 of the entire length of the output cone of the bar L_out. The interval of the transverse channels, the interaxial distance of the longitudinal and transverse channels, the distance from the upper edge of the channel cavity to the lower edge of the surfaced layer are prescribed. The longitudinal and transverse channels are in the same plane.

EFFECT: increase wear resistance of the working surface of the piercing mill bars.

4 cl, 4 dwg