GRATE FOR SCREEN AND METHOD OF ITS MANUFACTURING Russian patent published in 2005 - IPC

FIELD: metallurgy.

SUBSTANCE: grate has openings made of oval slots arranged on the grate to form herringbone rows whose tops point counter to the flow of material to be screened. The ends of the openings are arranged with a step H = 2V/f, where V is the velocity of the material flow and f is the number of oscillations of the screen per unit time. The distance between the axes of the parallel openings, h, is equal to the distance between the lines which connect the centers of the semicircles of the one-directional ends of the openings in the adjacent rows. The cross-sections of the openings diverge in the grate bulk from its working surface with an angle 5-7°. The working edges of the openings are strengthened through a thickness of 0.5-1.5 mm. The width of the openings, d, is equal to at least 3 mm, and their length is (2-10)d. The method comprises making openings by air-plasma cutting with simultaneous strengthening the working edges of the openings by fast high-temperature heating with the use of a concentrated plasma jet and fast forced cooling.

EFFECT: enhanced efficiency and accuracy of screening.

7 cl, 7 dwg