SU997901A1 - Bent section manufacturing method - Google Patents

Description

The invention relates to the processing of metals by pressure, in particular to the production of curved profiles in rolls of bending mills.

A known method for the production of curved rolled profiles, inclusive of successive hemming of profile elements along transitions, in which initially bend places of greater curvature than the given one, and then carry out the final otFOE 1Ovka profile, compress the profile along the outer contour Cl.

The disadvantage of this method; its limited use is only for box profiles. When using the known. It is capable of making profiles open: it is impossible to create a compression on the outer contour, and therefore prevent springing of the bend points.

The aim of the invention is to improve the quality of the profiles by reducing the springback of the places of bending.

 This goal is achieved by the fact that, according to cnocoJ5y, pinging of curved profiles,: ■ include {he successively hemming profile elements along transitions, at which the curvature points of the greater curvature are initially formed than the given one, and then the profile is finalized at the same time as the curvature of the curvature is greater the curvature than the addendum, forms a profile with an increased width of straight sections adjacent to the bend points to obtain specified angles between the profile elements, and during the final forming of the fil place pereformovyvgiot bending to a predetermined curvature is curved adjacent to them rectilinear. plots.

FIG. Figure 1 shows the technological transitions made by the channel in FIG. 2 is a diagram of a change in the place of bending. .

In accordance with the proposed method, in 1-Ш technological moves, by successively bending the workpiece 1, a channel is formed with a radius of curvature reduced by the value of Ap at bend points 2 for a Specified sweep width of bend points

25 2 and an increased width of adjacent straight line sections.

In 1U technological transition in the final, forming the profile, the curvature of the bend points 2 is reduced

Claims (1)

30 (the radius of curvature is increased to a given angle while maintaining the bending angle (d,). The increase in the radii of curvature from (f - Lr) to f at constant angles of bending of the shelves 3 relative to the wall 4 is provided by re-shaping the bend 2 and curving the curvature LA of adjacent rectilinear sections 5 During final shaping of profile IV, the transition is due to the fact that the radius of curvature increases from (p. -4Pc) to f, the springback is directed towards increasing the angle of bending of CCS, while it is usual when bending the spring. in a hundred It reduces the bending angle dt | (. To eliminate the spring back, the molding should be carried out in such a way that the radius of curvature (Do) before re-shaping the bend to the desired radius of curvature, takes into account the angle of the spring when bending the DYpr. At the same time, the curvature radius is determined by The formula () -5-Gl in a number of cases when forming profiles, when the action of transverse forces is observed at the places of bending, the magnitude of the angle of springback Lc should be somewhat smaller. So, for example, when forming a research institute profile of 60x161 mm from St. Zl steel / for greenhouses, the elements of the workpiece are hemmed on a .9-stand mill 1-3x20-350 in 8 technological transitions. In this case, the corners of the hem at the transitions are, up to the side wall 0-10-20-40-50-60-75-75 ° and for flanging 0-20-40-60-80-90-120-120, and the radii the curvature at the points of bend in the first 2-7 transitions (equal to 1.1-1.2 mm, and in the last transition the radius of curvature increases to the previously obtained given angles between the profile elements 75 and 120 °. The profiles made according to the proposed method, characterized by the fulfillment of predetermined angles between flat elements, the shaping of a bend point according to a given radius of curvature and a good surface quality without scratches, At the same time, the metal thinning at the bend sites is reduced, the energy consumption for molding and wear in the cove is reduced. Thus, according to the proposed method, when shaping the 60x16x1 mm L profile of the greenhouse tray, angles 75 and 120 ° between the profile elements c are provided - by deviations up to 0.6 ° when thinning 2-3% of the thickness, while by a known method the deviations are up to 3, and in the last passes during the molding by the known device the thinning up to 10%, the appearance of scratches and tears on surface profiles. The use of the proposed method for the manufacture of profiles in comparison with the known method allows to reduce energy consumption by 10-20% by eliminating transverse stretching of flat areas and places of bending and reducing friction losses in the caliber of the rolls. The use of the invention in the manufacture of bent profiles for a greenhouse tray will allow organizing their production at the mill greenhouses, which will provide, with a production volume of 50 thousand tons, an annual effect in excess of 100 thousand rubles. The economic effect will be obtained by reducing the metal intensity of the profiles by 20%, reducing transport costs, laboriousness of making profiles and assembling structures from them by 20%. The invention method of making curved profiles, including the successive hemming of elements of the profile of transitions, in which the initial shape of the curvature of the curvature than the specified, and then carry out the final forming of the profile, and the length of the curvature is , in order to improve the quality of the profiles by reducing the springback of the bending places, simultaneously with the forming of the bending places of greater curvature than the given one, the profile with the increased width of the straight sections adjacent to the bending places is formed predetermined angles between the profile elements, and during the final bending profile otformovki pereformovyvayut space to a predetermined curvature is curved adjacent to them straight portions. Sources of information taken into account in the examination 1. Production and use of curved profiles. Handbook ed. I.S Trishevsky, M., Metallurgists, 1975, p. 203-216 (prototype). I nepeiaff / Sh k V