RU2758605C1 - Method for manufacturing a hot-rolled i-beam from a shaped blank - Google Patents

Abstract

FIELD: working of metal.

SUBSTANCE: invention relates to rolling manufacture, in particular, to manufacture of I-beam profiles. A method for manufacturing a hot-rolled large-sized I-beam from a shaped blank, including manufacturing a shaped blank on a continuous casting machine or by pre-rolling, heating to a temperature of 1,150 to 1,280°C followed by removing scale, rolling on a breakdown mill and a group of universal and auxiliary mills of a universal beam-rolling mill, and cooling. An I-beam with conditional height dimensions of 800 mm, 900 mm, 1,000 mm is made from a shaped blank made in the form of a column with parallel opposite shelf sides. Prior to rolling, the shaped blank is heated to a temperature of 1,100 to 1,200°C, and rolling is executed on a breakdown mill or at least two breakdown mills, then rolling is executed on two - pre-finishing and finishing - or more groups of universal mills.

EFFECT: manufacture of large-sized I-beams from a blank of one standard size is ensured as a result.

2 cl, 2 dwg, 1 tbl

Description

The invention relates to rolling production, in particular to the production of I-profiles.

The known "Method of transferring rough rolls of an I-beam on

horizontal outline "[1] Inventor's certificate No. 378265 SU" Method of transferring rough rolls of an I-beam along a horizontal outline ", MPK3 B21B 1/08 B21B 41/06; B21B 108/04, where in order to ensure self-rolling of the roll at 90 ° when entering rounding of the contour and spontaneous reverse tilting when leaving it, in the rolls of the release stand, the open bottom flanges of the profile are bent from the vertical at an angle of 35-45 °, while keeping the walls and flanges straight, and before entering the receiving stand, the lower flanges are bent back to their normal position.

The disadvantage of this method is that the possibility of this method is limited by the dimensions of the rolled profile, and with the overall dimensions of the profile there is no need for self-edging, and a significant change in the shape of the billet during rolling in rough passes is aimed at giving the preliminary shape and dimensions of the resulting I-beam profile, which is significantly different from each other ...

The closest (prototype) in technical essence to the declared

the method, according to the number of similar features, is "Method for the production of an I-beam and a casting and rolling complex for its implementation" patent RU 2620212 C1 [2], where after removing the workpiece from the centrifugal casting machine it is heated to a temperature of 960-1050 ° C and rolled into a two-tee beam in 4-6 passes in a reversible roughing and finishing universal rolling mill stands, with a total draft of 1.7-3.5.

The disadvantage of this method is that the workpiece repeats the shape of the shell with 2 ridges. Also, the disadvantage is that in the first pass of the crimping stand, the section of the workpiece between the ridges with a drawing of 1.15-1.25 is compressed with horizontal rolls, with the formation of a vertical I-beam post from it with a turn of the ridges and side branches by 15-75 °, and with vertical rolls bend the ridges and side branches with the formation of symmetrically concave horizontal flanges of the I-beam, which is impossible for large I-beams. Also, the disadvantage is that the workpiece is designed according to the dimensions of the finished profile, and the manufacture of several standard sizes from one workpiece is impossible.

The technical result to achieve which the alleged invention is directed is: the manufacture of large-sized I-beams 80SH1, 80SH2, 90SH1, 90SH2, 100SH1, 100SH2, 100SH3, 100SH4, 90DB1, 90DB2, 90DB3, 90DB4, 90DB5, 90DB6, 100DB1, 100DB3 of one size ...

The specified technical result is provided due to the fact that in the method of manufacturing a hot-rolled large-size I-beam from a shaped billet with nominal height dimensions of an I-beam 800 mm, 900 mm, 1000 mm, including the production of a shaped billet on a continuous casting machine or by pre-rolling, heating to a temperature of 1150-1280 ° With further descaling; rolling on a crimping stand and a group of universal stands having auxiliary stands available, cooling, according to the invention, rolling of I-beams is carried out from a workpiece of one standard size, moreover:

- for I-beams 1000 mm, if there are 2 calibers on the swaging stand, the billet is rolled on the swaging stand in 7-9 passes without upsetting the workpiece, in addition, in the case of 2 or more swaging stands and the possibility of placing 3-4 calibers, the billet is rolled in a larger number of passes - up to 11 passes, and then rolling is carried out on a universal beam mill with a minimum of 13 passes in the presence of only 2 groups of stands - pre-finishing and finishing, and with a large number of passes, in the presence of several groups of universal stands;

- for I-beams 900 mm, if there are 2 calibers on the swaging stand, the billet is rolled in the swaging stand for 7-9 passes with the billet upset in the first passes, in addition, in the case of two or more swaging stands and 3-5 calibers, the billet is rolled carried out in a larger number of passes - up to 11 passes, and then rolling is carried out on a universal beam mill with a minimum number of 11 passes in the presence of only 2 groups of pre-finishing and finishing stands, and with a large number of passes - up to 17, in the presence of several groups of universal stands;

- for I-beams 800mm, if there are 3 calibers on the swaging stand, the billet is rolled in the swaging stand in 7-9 passes, with the billet upsetting in the first passes, while, in the case of two or more swaging stands and 4-5 calibers the billet is rolled in a larger number of passes - up to 11 passes, and then rolling is performed on a universal beam mill with a minimum number of 11 passes in the presence of only 2 groups of stands - pre-finishing and finishing, and with a large number of passes - up to 17 passes, with the presence of several groups of universal stands.

In addition, for rolling 900 mm I-beams, the billet is upset in the first passes for 2 passes, in a box gauge 2, located in the center of the finished open beam gauge 4.

Distinctive features of the claimed method are:

- the billet is produced on a continuous casting machine or by pre-rolling, and then heated to a temperature of 1100-1200 ° C before rolling;

- the shape of the workpiece (FIG. 1.), is a formed stand with parallel opposite edges of the shelves 4, in contrast to the analogue, where the workpiece repeats the shape of the shell with two ridges;

- in the case of rolling I-beams 100, in the first pass of the roughing stand, both the wall and the surfaces of the flanges with drawing 1.1-1.2 are crimped, in the production of I-beams 80, in the first pass of the roughing stand the billet settles in a box gauge along the height of the I-beam, in the production of I-beams 90 upsetting of the billet in the first passes in the box groove 6 (FIG. 2), which is cut in the center of the finished open beam groove 8 (FIG. 2.), is carried out in two passes (FIG. 2.) and then rolling proceeds along schematic diagram of rolled 80 beams;

- the use of one standard size of a shaped non-perforated cast or pre-rolled billet for the manufacture of large-size I-beams 80-90-100, in contrast to the analogue, where the billet is calculated according to the dimensions of the finished profile.

The invention is illustrated by drawings:

Fig. 1 is a cross-section of the workpiece, where 1 is the side flanges, 2 is the radius of conjugation, 3 is the wall, 4 is the shelf; H is the height of the workpiece; B is the width of the workpiece; a is the width of the base of the flange; s is the width of the top of the flange; R - values of the radii; t is the wall thickness.

FIG. 2 - box gauge for upsetting, where 5 - workpiece in the process of upsetting, 6 - box gauge, 7 - workpiece in the process of distillation, 8 - beam gauge.

The essence of the proposed method is as follows:

In the process of manufacturing hot-rolled large-size I-beams from a shaped billet, a shaped billet is used, obtained on a continuous casting machine or by preliminary rolling of an ingot on a blooming mill. The dimensions and area of the workpiece are determined based on the total degree of reduction and total stretching, and the shape of the workpiece is calculated taking into account the broadening coefficients, the conditions of metal flow along the sliding lines on the side flanges 1 and the filling of the shelves 4. Due to the fact that the filling of the shelves 4 is determined by the degree of reduction and the coefficient of friction on the side surfaces of the flanges 1, as well as leading and lagging zones to ensure complete filling of the shelves 4 with metal, transition radii of conjugation 2 are used, defined as R = 0.6-0.85 of the value of the smallest of the two parameters: the length of one flange 1 or half the length of wall 3. In the process of rolling, reduction along wall 3 and flange 4 occurs with a decrease in the degree of reduction with each subsequent pass, respectively, the main formation of widening of the flanges occurs in the first passes with the determination of the ratio of the height of the I-beam to its width, in finishing passes the increment of the width of the flange 4 is approximately in direct proportion to the broadening in wall 3.

Figure 1 is a blank consisting of a wall 3 with two flanges 4 perpendicular to it, each formed by two flanges 1 having a width (a) at the base and a width (s) at the top. The wall 3 has a thickness (t) and is mated with the flanges 4 along the width of the flanges at the base (a) by the mating radii 2, with the values of the radius (R). The width of the blank (B) is characterized by the width of the flanges 4, and the height of the blank (H) is characterized by the height of the wall 3, while the height of the finished I-beam (H ') determines the boundary condition for determining the range of possible blanks.

The proposed method for manufacturing a large-sized hot-rolled I-beam from a shaped workpiece is to manufacture the following I-beams: 80SH1, 80SH2, 90SH1, 90SH2, 100SH1, 100SH2, 100SH3, 100SH4, 90DB1, 90DB2, 90DB3, 90DB4, 90DB5, 90DB1 100DB6, Continuously cast or pre-rolled shaped billets with surface quality ensuring the absence of unacceptable defects on I-beams. After heating the billet in a furnace to a temperature of 1150-1280 ° C, descaling by means of descaling or mechanically, it is transferred to a crimping stand for further rolling at a temperature of 1100-1200 ° C. When rolling 100 I-beams, the billet is rolled in 7-9 passes on a swaging stand in the presence of two calibers and for a greater number of passes - up to 11, in the presence of two or more swaging stands, and the possibility of placing 3-4 calibers, and then on a universal a beam mill with a minimum number of 13 passes in the presence of only two groups of stands - pre-finishing and finishing, and with a large number of passes - up to 19, in the presence of several groups of universal stands.

When rolling I-beams 90 in a swaging stand, rolling is carried out in 7-9 passes, in the presence of two calibers (one of which is special - finishing with a box gauge FIG. 2) and for more passes up to 11, in the presence of two or more swaging stands and 3 -5 calibers, and then on a universal beam mill with a minimum number of 11 passes in the presence of only two groups of stands (pre-finishing and finishing), and with a large number of passes - up to 17, in the presence of several groups of universal stands.

When rolling I-beams 80 in a swaging stand, rolling is carried out in 7-9 passes, in the presence of three calibers and for a greater number of passes - up to 11, in the presence of two or more swaging stands and 4-5 calibers, and then on a universal-beam mill with a minimum the number of 11 passes in the presence of only two groups of stands - pre-finishing and finishing, and with a large number of passes - up to 17, in the presence of several groups of universal stands.

After rolling through all groups of stands, the rolled profile is transferred to a cooler with forced cooling or natural cooling.

I-beams of various sizes with nominal height dimensions of 800 mm, 900 mm, 1000 mm, have both different heights of the wall 3 and different widths of the shelves 4. The height of the profile of the finished I-beam (H ') obtained by the hot-rolled method cannot be greater than the height of the workpiece ( H), because during rolling, the processes of reduction and broadening occur, and tensile stresses can lead to axial segregation in the profile wall, therefore, one of the boundary conditions is H> H ’, where (H’) is the height of the finished I-beam, and (H) is the height of the workpiece. With a significant decrease in the height of the finished I-beam (H '), relative to the height of the workpiece (H), there is a need for upsetting of the workpiece in height, after which there is a broadening along the thickness of the wall 3, as well as broadening with an increase in the width of the shelf 4.

The proposed solution of using one standard size of a non-perforated cast or pre-rolled billet for the manufacture of large I-beams 80-90-100 can be carried out on a universal beam mill using a crimping stand and a group of universal and auxiliary stands.

An excessive increase in the thickness of the wall 3 and the width of the shelf 4 leads to the need to use additional calibers that limit the growth of the width of the shelf 4 and additional passages for further displacing the metal from the wall 3 into the flanges 1 with performing plastic deformation simultaneously along the shelf 4 and wall 3 of the caliber, for this purpose, boundary conditions for each beam are given in table 1.

Table 1.

Boundary conditions for the rolling scheme for the production of large-sized hot-rolled I-beams.

I-beam I-beam 80 I-beam 90 I-beam 100 Number of calibers of the blooming stand 3-5 2-5 2-4 The presence of a box gauge in the upsetting cage Yes Yes No The presence of split grooves in the blooming stand for distillation Yes Yes Yes Number of passes in the blooming stand 7-11 7-11 7-11 The minimum required number of groups of universal stands 2 2 2 Number of passes in universal gauges 11-17 11-17 13-19 Total draw ratio 8.3-9.7 5.8-8.4 5.0-7.2 Total reduction ratio 8.5-9.3 6.1-8.0 6.1-7.5 Rolling start temperature 1100 ° C-1250 ° C 1100 ° C-1250 ° C 1100 ° C-1250 ° C End rolling temperature 800 ° C -900 ° C 800 ° C -900 ° C 800 ° C -900 ° C

The peculiarity of rolling I-beams 90SH1, 90SH2, 90DB1, 90DB2, 90DB3, 90DB4, 90DB5, 90DB6 is that the draft of the billet in the first passes in the box groove 6 FIG. 2, which is embedded in the center of the finished open beam gauge 8 FIG. 2., is carried out in two passes of FIG. 2. And then it goes according to the basic scheme of rolling 80 beams, with the last omissions of FIG. 2., In the same finishing caliber 8. FIG. 2.

The technical and economic effect of the method for the production of a hot-rolled large-size I-beam from a shaped billet is to reduce the cost of manufacturing a shaped billet with a different cross-section, individual for each profile obtained, associated with the manufacture, replacement of molds, and the setting of a continuous casting machine for an individual operating mode.

Sources of information:

[1] Inventor's certificate No. 378265 SU "Method for transferring rough rolls of an I-beam along a horizontal outline", IPC ³ B21B 1/08 B21B 41/06; B21B 108/04;

[2]. Copyright certificate No. 1034804 SU (application No. 3406284 / 22-02) "Device for automatic braking of rolled products to a given speed" copyright certificate, IPC ³ В21В37 / 00, published on 15.08.83, bul. No. 30.

Claims (2)

1. A method of manufacturing a hot-rolled large-size I-beam from a shaped billet, including the manufacture of a shaped billet on a continuous casting machine or pre-rolling, heating to a temperature of 1150-1280 ° C with further descaling, rolling on a crimping stand and a group of universal and auxiliary stands of a universal beam mill and cooling, characterized in that an I-beam with nominal height dimensions of 800 mm, 900 mm, 1000 mm is made from a shaped billet made in the form of a rack with parallel opposite edges of the shelves, while the shaped billet is heated to a temperature of 1100-1200 ° C before rolling and rolling is carried out on a swaging stand or at least two swaging stands, then rolling is carried out on two - pre-finishing and finishing - or more groups of universal stands, and when receiving an I-beam of 1000 mm, 2 gauges are used on a swaging stand and the shaped billet is rolled in a swaging stand in 7-9 passes without upsetting of the shaped billet or 3-4 caliber on at least two swaging stands and rolling of the shaped billet is carried out in a larger number of passes - up to 11 passes, while in the first pass of the roughing stand the wall and surfaces of the flanges are compressed with a drawing of 1.1-1.2 , then rolling is carried out on a preparatory and finishing group of universal stands with a minimum number of 13 passes or with a large number of passes - up to 19 passes - with more than two groups of universal stands, when obtaining an I-beam of 900 mm, 2 gauges are used on a crimping stand and the shaped billet is rolled in the crimping stand for 7-9 passes with upsetting the shaped blank in the first passes or 3-5 calibers on at least two crimping stands and the rolling of the shaped blank is carried out in a larger number of passes - up to 11 passes, then rolling is performed on the pre-finishing and finishing group of universal stands with a minimum number of 11 passes or with a large number of passes - up to 17 - p with more than two groups of universal stands, when receiving an I-beam of 800 mm, 3 gauges are used on the swaging stand and the rolling of the shaped billet is carried out in the swaging stand in 7-9 passes with the upsetting of the shaped billet in the first passes or 4-5 gauges on at least two swaging stands and the rolling of the shaped billet is carried out in a larger number of passes - up to 11 passes, then rolling is carried out on the pre-finishing and finishing universal stands with a minimum number of 11 passes or with a large number of passes - up to 17 passes - with more than two groups of universal stands. 2. The method according to claim 1, characterized in that for rolling a 900 mm I-beam, the billet is upset in the first passes for 2 passes in a box gauge located in the center of the finished open beam gauge.

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