METHOD OF GUARANTEEING SUFFICIENT TECHNICAL RESOURCE OF CRANE GIRDERS Russian patent published in 2016 - IPC B21B1/46 E01B5/00 B66C7/08 C21D9/04 B66C5/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy. In order to ensure service life and endurance under-rail areas with a heavy crane girders 8K, 7K mode of operation of overhead cranes during intensive operation produced continuously-cast billets in the portal section of steel 35GS, it is cooled to a temperature of 950÷1050 °C, for roller tables progressively transported it into the rolling mill, fully crimped its rolling mill rolls from four sides and plastically deform the cross section of the portal to the project size with a total reduction ratio of not less than 7.8 to form a mirrored pair of Z-profiles single, monolithic Portal profile with one head and a pair of heels, and the sectional area of the head and a pair of heels are equal to each other, cut finished steel to length and installation of portal rail to the upper belt crane girders couple toe rail and the upper belt crane girders mechanized combined into a single unit friction stud, with a guarantee of tightening the nuts wrench, form a single closed gantry rail with a longitudinal cavity inside, which has increased inertia in torsion $${\displaystyle \sum J_{cr}^{block}}$$ 16.2÷10.6 times, and the moment of inertia in bending $$J_X^{block}$$ 5.2÷6.4 times as compared with the standard rail according to GOST 4121-76.

EFFECT: ensuring guaranteed service life and endurance of under-rail areas with a heavy crane girders 8K, 7K mode of operation of overhead cranes during heavy use.

2 dwg, 4 tbl