RU2788416C1 - Z-profile editing method - Google Patents

Abstract

FIELD: rolling production.

SUBSTANCE: invention relates to rolling production and can be used when straightening shaped profiles in a horizontal type roller straightening machine with adjustment of the axial displacement of the rollers. A load is created on the wall and shelves of the profile by bandages of the rollers of the passes of the roller straightening machine. In this case, bandages are used with a groove bored out in the rib cavities, having a depth of 2 to 10 mm and a width of 15 to 40 mm. Pairwise axial displacement of the roller bandages relative to the straightening line is carried out to provide a zone of contact between the bandages and the shelves in turn. First, a zone of contact of the lower bandage with the support shelf of the Z profile is created with the creation of a dispersed force. Then, a zone of contact of the upper bandage with the welded flange of the Z profile is provided with the creation of a dispersed force.

EFFECT: reduced curvature defects, full straightening in fewer passes and increased durability of roller tyres.

1 cl, 2 dwg

Description

The invention relates to rolling production, in particular to methods for straightening shaped profiles using a horizontal type roller straightening machine with adjustable axial displacement of the rollers.

A known method of straightening flange profiles patent RU No. 2203757 C2 (application No. 2000108501/02 dated 04.04.2000, IPC ⁷ B21D 3/16, publ. 06/10/2003), including the impact on the profile flange with alternating forces applied in a checkerboard pattern in one plane perpendicularly to the flange surface, moreover, the impact on the flange by alternating loads is carried out in two sections along its width, located symmetrically with respect to the axis of the flange.

The disadvantage of this invention is that using this technology it is possible to edit only symmetrical profiles.

The known method is "APPARATUS FOR STRAIGHTENING OF WELDED GIRDERS patent GB No. 1355431 (A) (application GB No. 34649/71 dated July 24, 1970) B21D3 / 16; B21D7/08; (MPK1-7): B21B1/10; B21D3/02, publ. 1974-06-05, where a welded beam of angular section is corrected by simultaneous rolling and bending of the beam in the area of the welded joint between wall 2 and chord 3, fig. 3 with upper and lower rolls 6, 7 located between a pair of bending rolls 8, 9, rolling in a plane containing the axes of the upper and lower rolls, in which the greatest bending stresses will occur.

The disadvantage of this invention is that the proposed technology applies to welded profiles, and the total bending moment is distributed along the edges of the profile.

The closest (prototype) in technical essence to the claimed device, in terms of the number of similar features, is the invention "Method of manufacturing bent Z-sections" patent RU No. ^2065791 C1 (application No. 27.08.1996), which includes, sequentially along the transitions, bending the profile shelves to the same angles, characterized in that in the manufacture of bent Z-shaped profiles with finite bending angles between the wall and the shelves exceeding 90 °, bending along the transitions is carried out with plane-parallel movement of the shelves each relative to each other simultaneously with the rotation of the wall around the axis of the mold, passing through its center of gravity in the direction opposite to the direction of bending the shelves, in each transition at an angle equal to the angle of bending the shelves in this transition, and in the pre-finishing transitions, the shelves are bent along the radius and then straightened with fixation free ends of the shelves, ensuring the movement of the bending points between the wall and the shelves in mutually opposite directions to the desired position.

The disadvantage of this invention is that the technology is used for bent from a sheet, and not for a hot-rolled Z-shaped profile, while everything happens in a roll forming complex with a large number of rollers.

The technical result to which this invention is directed is:

- reduction of residual twisting of the profile after one pass, the possibility of eliminating the curvature of a profile with a high crescent and, as a result, a decrease in curvature defects;

- displacement of the total bending moment of dressing to the center of the profile, respectively, a decrease in the cantilever load on the bearings and, as a result, an increase in the working load of the roller straightening machine, with the implementation of full straightening in fewer passes, uniform distribution of the load over the surface of the bandage, and a decrease in wear, with an increase in the resistance of the bandages in 2 times.

The specified technical result is achieved by the fact that the method of straightening the Z-profile, including the task of the strip in the roller straightening machine and straightening it with the pass rollers, according to the invention, the bandages of the paired rollers are displaced along the straightening axis, while providing the contact zone of the bandage alternately, first the lower bandage 3 with the support shelf 5 with the creation of a dispersed force Q2, and then the upper bandage 2 with a welded shelf 6 with the creation of a dispersed force Q1.

In addition, grooves 7 are machined to a depth of 2 to 10

mm with a width of 15 to 40 mm, with the release of the corner zone of the profile from direct contact with the bandage, and the total bending moment is shifted closer to the center of the profile.

Reducing the size of the groove groove to a depth of less than 2 mm and a width of less than 15 mm will lead to an insufficient effect and contact of the Z-profile with the groove surface will be created, which will make it impossible to work according to the proposed scheme.

Increasing the size of the groove groove to a depth of more than 10 mm and a width of more than 40 mm will lead to a lack of contact on the surface of more than 40 mm, and as a result, to a possible residual curvature of the profile during dressing along the contact surface with grooves.

Pairwise displacement of the roller bandages along the straightening axis, with provision of the bandage contact zone alternately, first of the lower bandage 3 with the support shelf 5 with the creation of a dispersed force Q2, and then the upper bandage 2 with the welded shelf 6 with the creation of a dispersed force Q1, provides the possibility of straightening the Z-profile, with a shift in the loading moment, due to the use of bored grooves in the rib cavities and the axial displacement of the bands relative to the initial dressing line to create a variable load on the profile wall and flanges, which favorably affects the dispersion of stresses and the quality of the dressing.

The technical essence of the invention is illustrated by drawings, which show:

FIG.1. The existing editing scheme, the location of the skip rollers.

FIG.2 The proposed editing scheme is a load scheme of forces and moments.

Where: Q1 is the resultant from the contact of the upper shroud with the welded flange 6;

Q2 - resultant from the contact of the lower shroud with the support shelf 5;

Ms is the total bending moment.

Description of reference position numbers:

1 - profile wall;

2 - upper bandage;

3 - lower bandage;

4 - profile clamping surface;

5 - support shelf;

6 - welded shelf;

7 - groove.

In the process of editing the Z-profile (in particular, the profile Z of the main beam of the pivot assembly of railway cars) (Figure 1.), the main load falls on the profile wall 1, which is characterized by a tight clamping of the profile wall 1 between the upper 2 and lower 3 bandage along the surface 4. Also the maximum torque falls on the surface closer to the top of the cavity 7, and this place of the bandage, due to the design features, has a minimum hardness, due to the maximum depth, where in the process of volumetric hardening, which is used during heat treatment of the bandages, the hardened layer is removed to the maximum, therefore, in the process of working in this zone 7, as the bandage wears out, the quality of dressing decreases.

This method is carried out as follows:

To ensure more uniform dressing, groove 7 is turned to a depth of 2 to 10 mm and a width of 15 to 40 mm, with the release of this zone from direct contact (Fig. 2), then dressing is carried out due to pairwise axial displacement of the bandages, providing a zone of contact of the bandage alternately lower bandage 3 with support flange 5, creating dispersed force Q2 and upper bandage 6 with welded flange 7, creating dispersed force Q1, which reduces the total bending moment Ms on wall 1, shifting its resultant to the center of wall 1, while creating a favorable condition for dressing, as well as more uniform wear of the surface of the tires.

This method can be implemented using a horizontal type roller straightening machine with adjustable axial displacement of the rollers.

So, for example, the proposed method was tested in the rail and beam shop at JSC "EVRAZ Nizhny Tagil Iron and Steel Works" in the manufacture of the Z310 profile, intended for the further manufacture of the center beam of the pivot assembly of railway cars from Steel 3sp, which had a wall height of 310 mm, a width of the supporting shelf 130 mm, welded shelf width 186 mm. According to the developed technology for this method, the profile was formed in six transitions, while the bending of the shelves was carried out in one transition.

Measurements of Z310 mm Z-profiles, made by this method and by the method known from the closest analogue, made it possible to establish the following deviations:

- the actual angle between the welded flange and the wall was 90±0.3º,

- the actual angle between the support flange and the wall was 90±0.2º, which significantly exceeds the requirements of GOST 5267.3-90

Thus, this technical solution meets the criterion of "novelty".

The use of the proposed method of straightening the Z-profile provides the possibility of straightening the Z-profile, with a shift in the loading moment, due to the use of bored grooves in the rib cavities and the axial displacement of the bandages relative to the initial straightening line to create a variable load on the wall and flanges of the profile, which favorably affects the dispersion of stresses and editing quality.

The analysis of patents and scientific and technical information did not reveal the use of new essential features used in the proposed solution. Therefore, the present invention meets the criterion of "inventive step".

It is confirmed that the use of this invention has the following effect:

- reduction of residual twisting of the profile after one pass;

- the ability to eliminate the curvature of the profile with a high crescent;

- displacement of the total bending moment of dressing to the center of the profile, respectively, a decrease in the cantilever load on the bearings and, as a result, an increase in the workload of the roller straightening machine, with the implementation of full straightening in fewer passes;

- uniform distribution of the load over the surface of the bandage, and a decrease in wear, with an increase in the durability of the bandages by 2 times.

Sources of information

[1] Patent No. RU 2203757 C2 (application No. 2000108501/02 of 04.04.2000) MPK7 B21D 3/16, publ. 06/10/2003, "METHOD OF EDITTING FLANGED PROFILES".

[2] Patent No. GB1355431 (A) (Application No. GB 19710034649 19710723 dated July 24, 1970) B21D3/16; B21D7/08; (MPK1-7): B21B1/10; B21D3/02, "APPARATUS FOR STRAIGHTENING OF WELDED GIRDERS", publ. 1974-06-05.

[3] Patent RU 2065791 C1 (application No. 92002525/08 dated October 27, 1992) MPK6 B21D 5/06, publ. 08/27/1996 "Method of manufacturing bent Z-sections".

Claims (1)

A method for straightening a Z-profile having a wall and a supporting and welded flange, including creating a load on the wall and profile flanges by bandages of the rollers of the passes of the roller straightener, while using bandages with a groove bored in the rib cavities, having a depth of 2 to 10 mm and a width of 15 to 40 mm, and a pairwise axial displacement of the roller bandages relative to the straightening line is carried out with the provision of a zone of contact between the bandages and the shelves in turn, and first the zone of contact of the lower bandage with the support shelf of the Z profile is provided with the creation of a dispersed force, and then the contact zone of the upper bandage with the welded shelf of the Z profile profile with the creation of a dispersed effort.

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