METHOD OF MAKING HIGH-ACCURACY MANIFOLD SECTIONS Russian patent published in 1997 - IPC

FIELD: manufacture of high-accuracy manifold sections. SUBSTANCE: method comprises steps of preliminarily rolling initial blanks, assembling them to paired blank, sharpening leading ends of paired blank in common edge roll grooved pass of sharpening rollers in single pass; tilting paired blank by 90 degrees without changing mutual arrangement of initial blanks, introducing template between leading ends of initial blanks along length of their sharpened end portions; guiding paired blank and template to common rhombic roll grooved pass for preliminary rolling them until formation of trapezoidal cross section of their leading ends; using hexahedral cross section rod with sharpened lateral faces of its front end as template. Rod has constant height Hm = Hk - (0.1-015) mm, where Hk - height of common rhombic roll grooved pass from bottom of its grooves, (0.1-015) mm - gap value between template and groove walls. Angles between faces of grooves non joining with blanks have fixed values; each angle β = 180 degrees - a_r.s. sect., where α_r.s. sect. - angle between lateral faces of ready section. As-preliminarily rolled blanks are subjected to finish deformation in one-piece drawing dies. EFFECT: enhanced efficiency. 6 dwg