METHOD TO MANUFACTURE PERFORATED BEAM Russian patent published in 2015 - IPC E04C3/08 

FIELD: construction.

SUBSTANCE: manufacturing of a perforated beam is carried out by cutting align the axis of the wall of a rolled double-tee shape with a certain cutting line for each half of the beam and welding of protruding parts of halves to produce holes in the wall in the form of an ellipse. Cutting lines are set with the possibility to produce in a wall, after welding, the elliptical openings with different angle of inclination of the main axis of the ellipse to the axis of the beam. It is possible to arranged a central elliptical opening in the wall, with the main axis located perpendicular to the longitudinal axis of the beam, and others - at the angle of 45 degrees symmetrically to the centre of the beam. It is also possible to produce elliptical openings in the wall, which have the angle of inclination smoothly changing from 90 degrees in the centre of the beam to 45 degrees in support sections symmetrically to the centre of the beam.

EFFECT: increased reliability and durability of a perforated beam due to reduced concentration of stresses in its wall.

3 cl, 9 dwg, 1 tbl