| 摘要 |
FIELD: metallurgy, possibly sizing and further rolling in rough passes railway road rails or similar shapes of continuously cast billets. SUBSTANCE: method for rolling railway road rails in rough rolling passes comprises steps of rolling in box groove pass where billet is upset along its faces designed for forming web of rail; preliminarily cutting faces of billet designed for forming flange and surface of rolling surface rail head in unsymmetrical pass such as in beam pass with different heights of slit ridges; upsetting cut faces in box pass and preparing rolled piece in such pass after tilting it by 90 degrees for rolling in next trapezoidal grooved pass with deep cut of face designed for forming rail flange; determining height of cut faces of unsymmetrical slitting pass depending upon height of slitting pass according to expressions hhr.h. = (0,12-0,14)Hsl; hr.f. = (0,05-0,07)Hsl where Hsl - height of slitting pass; hr.h. - height of ridge at side of rail head; hr.f. - height of ridge at side of rail flange. Apex angles of ridge are no less than 130 degrees (alpha>=130°). Invention provides shifting of axial liquation and porosity relative to center of billet. It prevents occurrence of flaw zone in head of rail. EFFECT: enhanced quality of rolled rails. 5 dwg, 1 tbl, 1 ex |
