METHOD OF BUSH SLEEVE RECEIVING Russian patent published in 2009 - IPC B21B19/04 

FIELD: metallurgy.

SUBSTANCE: method includes separation of workpiece blanks for measured lengths, heating, plugless cobbing of workpiece blank in three-high gauge of primary mill and broaching of measured lengths workpiece blanks. Heating of workpiece blanks is implemented before separation for measured lengths. Temperature of each workpiece blank of measured lengths before broaching is kept constant by means of increasing of number of revolutions primary mill rollers in the range 1-30%. Plugless cobbing in three-high gauge is implemented with percent reduction 20-30%, at feed angle of primary mill rollers, which is 1.0-1.6 of feed angle of primary mill rollers. Value of percent reduction of measured lengths workpiece blanks is changed in the range 0.95-1.04 subject to wearing of piercing mill rollers.

EFFECT: creation of efficient and economy method of bush sleeves receiving ensured by reduction of bush sleeves' thickness variation, increasing of durability and providing of wear uniformity of piercing mill rollers, and also reduction of power consuption during broaching and manufacturing wastes, related to formation of inner scabs and external surface defect.

3 cl, 2 tbl, 2 ex