RU1782686C - Method of straightening long-size intermediate products - Google Patents

Abstract

SUMMARY OF THE INVENTION: A section of a long workpiece (DZ) is clamped at two points and a transverse force is applied to it in the middle, bending and stretching the DZ. A stop is located on the opposite side of the DZ, which prevents the deflection of the DZ until the lateral force exceeds the value of the force that ensures the plastic deformation of the DZ. A transverse force acts on the convex side of the DZ site, upsetting it. Then, the DZ unloading value is measured and reprecipitated until its final straightening. Precipitation can be made from opposite sides of the DZ. 1 wp 2 ill.

Description

The invention relates to the processing of metals by pressure and can be used in straightening metal.

Correct multi-roller machines are known in which the workpiece is straightened between two rows of rollers (rolls) by the action of alternating multiple bending. This editing method is the most widespread in all branches of the metalworking industry (see certificate of research of the claimed object).

However, the used roll sheet and straightening machines have limitations on the size, shape and strength of the workpieces. The quality of straightening (4-15 mm per 1 m) of rolled products on these machines does not meet the requirements of metal processing enterprises (2-3 mm per 1 m).

To eliminate the noted drawbacks of dressing with multiple bends, dressing is used on stretch machines, which provides improved quality of dressing, the absence of a relationship between quality and ybitya. However, this straightening method requires a lot of tensile effort, which requires special, expensive equipment. In addition, in metallurgical production, to apply stretching dressing, it is usually necessary to dress in roller machines, where the arrow of buckling of buckles is brought to a value not exceeding 30 mm per 1 m.

To reduce the applied forces, stretching is carried out transversely by the applied force MKI. AT 21). This method is adopted as a prototype, since it is closest to the proposed one.

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The disadvantages of this method are the limited technological possibilities due to the need to tilt the workpiece due to the transverse force of the workpiece being curved in the application zone, as well as the need for a large deflection (up to 0.1 workpiece length) when dressing long workpieces.

The aim of the present invention is to expand the technological capabilities of straightening by stretching using transversely applied forces by eliminating the tilting of the workpiece and reducing its deflection under load.

To achieve this goal, the straightened workpiece is clamped with a force that does not allow the workpiece to move at a wavelength before plastic deformation begins, after which the wave is deposited in the curved workpiece by its amplitude with a measure of the elastic unloading, which is carried out secondary deposition before straightening blanks in a fixed area.

Depending on the direction of the wave amplitude, the upsetting force is applied to the upper or lower punch with a possible counterpressure by a free punch, which will increase the quality of dressing in flatness and will provide a more even distribution of residual stresses after dressing on the surface of the sheet.

In FIG. 1 shows a diagram for editing a sheet blank; Fig. 2 is a machine diagram when editing taking into account the Bausinger effect.

The workpiece 1 is fed into the working area of the press with pressure plates 2, which with a force of Q / 2 on each pair of plates fix the workpiece at a wavelength of 1 with amplitude, fo. The punch 3 with a force P can upset the workpiece with a possible counter-pressure of the punch 4 (see figure 1). The first stroke of the punch (deposition) is carried out by the amplitude of the dressing wave fo (line 5 in the machine diagram, Fig. 2), followed by unloading and measuring the residual loss f i (line 6). Then a secondary stroke of the punch is made. If it is produced by the value f2 2fi (line 1) without taking into account the Bausinger effect (decreasing the force from the value of P to the Pi line 8), then we obtain the residual wave Af opposite in the direction of the initial amplitude. Therefore, the secondary pressure of the punch is carried out by the stroke value h 2fi - Af (see Fig. 2).

Calculations show that the value of Af, taking into account the Bausinger effect, should be about 0.31.

An example of the use of the method in relation to the blanks of mill 5000 of Izhora plant.

The maximum power parameters when dressing in the cold state of a steel sheet with a thickness of 100 mm, a width of 3.2 m from a material with a yield strength of 1000 MPa at a dressing wavelength of 100 mm and an amplitude of 100 mm were: maximum force on the punch about 50 MN, maximum pressure about 10 MK.

A detailed calculation of economic efficiency is given in the appendix.

Claims (1)

1. The method of editing long workpieces, in which the processed section of the workpiece is stretched by fixing its ends and applying to the middle of the section transverse force directed perpendicular to the axis of the workpiece, characterized in that, in order to improve quality and increase productivity, to the workpiece on the opposite side from the application of lateral force brings an emphasis, ensuring bending of the workpiece from a transverse force exceeding the force required for plastic deformation in the workpiece, when this transverse force acting on the convex side of the workpiece, upsetting it on the size of the convex arrow, then remove the transverse force, measure the amount of unloading and make repeated upsetting of the preform until the final straightening of the preform portion. 2, The method according to claim 1, characterized in that the deposition is carried out from opposite sides of the workpiece. Tfi Punch stroke / g ft  asthenia te.2