RU2014935C1 - Method of making rectangular cross section forgings of low ductile steels and alloys - Google Patents

Abstract

FIELD: metal pressure forming. SUBSTANCE: method comprises steps of radially forging a heated ingot and forming a forging in a press; before forging in the press subjecting the ingot to radial-shear rolling until a normalized, diameter, performing forging process in the press with reduction value along a height of the blank and with widening, necessary for providing a width of a ready forging. EFFECT: simplified forging process of low ductile steels and alloys. 1 cl, 2 dwg

Description

 The invention relates to the processing of metals by pressure, in particular, to methods for manufacturing forgings of rectangular cross section from low plastic steels and alloys by forging and rolling.

 A known method of manufacturing forgings of rectangular cross section from low-plastic steels on radial forging machines [1].

 However, this method does not provide high quality metal in the axial zone of the obtained forgings and is not sufficiently productive.

 The aim of the invention is to improve the quality of forgings and process performance.

To do this, in the method of manufacturing rectangular forgings of low-plastic steels and alloys, including radial forging of the ingot and the subsequent formation of the forgings by forging on the press, before forging on the press, radial-shear rolling is carried out to a diameter determined from the relation:
d = (0.7 ... 1.0) b, where d is the diameter of the workpiece after radial shear rolling;
b is the width of the forgings of rectangular cross section, and forging on the press is carried out with compression along the height of the workpiece and broadening, providing the width of the finished forgings.

In FIG. 1 shows a diagram of the process for transitions, where 1 is the cross section of the ingot (d _sl . Is the diameter of the ingot); 2 - cross section of the workpiece after radial forging (d ^l - diameter of the workpiece); 3 - cross section of the workpiece after radial shear rolling (d is the diameter of the workpiece); 4 - cross section of the forgings after forging on the press (b - the width of the forgings, h - the height of the forgings).

 Figure 2 shows a diagram of the compression of a round billet into a strip in a special device mounted on a forging press, where 5 is the base; 6, 7 - side crawlers that can be set to the desired strip size in width; 8 - firing pin.

 The dotted line shows the cross section of the workpiece after radial-shear rolling, and shaded - the cross section of the forging after forging.

 The method is as follows.

Ingot with diameter d _cl. (figure 1) is heated and forged on a radial forging machine from a workpiece with a diameter of d ^l according to the circle-circle scheme with a drawing coefficient μ = 1.6-8.0. Due to the four-sided loading scheme of the workpiece during such forging, ingots of low-plastic steels and alloys are not destroyed, and the surface layer of the ingot metal is subjected to intensive deformation processing.

The resulting billet with a diameter of d ^{l is} heated and radial-shear rolling is carried out on a mill of RSP to a billet with a diameter of d with a drawing coefficient μ ₂ = 1.3-8.0.

 The radial shear rolling process is characterized by high productivity, and, in addition, it allows you to intensively work out the metal structure over the entire cross section of the workpiece without destroying it.

 Then, a workpiece of diameter d after forging is forged on a hydraulic forging press in a special device into a strip of width b and height h.

 Compression is carried out only along the height of the workpiece h, since the size along the width of the forging is ensured by the installation of lateral creepers 2, 3 in a certain position (Fig. 2). In this case, the workpiece before forging should be of diameter d = (0.7 ... 1.0) b, if d <0.7b, discontinuities on the surface of the workpiece are possible due to the intense metal flow during broadening. For d> b, the process is impossible, since the workpiece cannot be installed in the caliber of the device.

 The combination of radial forging, radial shear rolling and forging in the press provides high quality metal.

PRI me R. The ingot of 430 mm diameter steel R6M5K5 heated to 1160 ^{° C,} forged at a radial forging machine 10MN effort on blank 190 mm diameter (μ ₁ = 5.1). Forging is carried out in 5 passes according to the following scheme (diameters of the cross section of the workpiece along the passages are indicated, mm):
430 - 370 - 310 - 265 - 220 - 190.

The preheated to 1120 ^C. billet diameter of 190 mm is rolled on the mill radially-shear rolling FPR-200 (μ ₂ = 5) by the following scheme (shown cross-sectional diameters of the passages workpiece, mm):
190 - 160 - 120 - 85.

Then heated to 1160 C ^for 85 mm diameter billet is forged on a hydraulic press force of 5 MN in a special device according to the following scheme:
circle 85 mm - strip 100x60 mm - strip 100x40 mm
When implementing the method, the following ratio was maintained:
d = 0.85 b.

Claims (1)

METHOD FOR MANUFACTURING RECTANGULAR FORGING FROM MILOPLASTIC STEELS AND ALLOYS, including radial forging of the ingot and subsequent formation of forgings by forging on the press, characterized in that before the forging on the press radially-shear rolling of the workpiece to a diameter determined from the ratio is determined from the ratio
d = (0.7 - 1.0) b,
where d is the diameter of the workpiece after radial shear rolling;
b is the width of the forgings of rectangular cross section,
and forging on the press is carried out with compression along the height of the workpiece and broadening, providing the width of the finished forgings.

Images