1. The hot-rolled parallel leg channel steel comprises a waist plate and two parallel legs, and is characterized in that the height of the waist plate is 300-1000 mm.

2. The hot rolled parallel leg channel as claimed in claim 1, wherein the length of the parallel legs is 150mm to 500 mm.

3. A hot rolled parallel leg channel as claimed in claim 1 or claim 2, wherein the difference in length of the two parallel legs is no more than 15 mm.

4. A hot rolled parallel leg channel as claimed in claim 1 or claim 2, wherein the thickness of the web is not less than 20 mm.

5. A hot rolled parallel leg channel as claimed in claim 1 or claim 2, wherein the parallel legs are not less than 20mm thick.

6. A hot rolled parallel leg channel as claimed in any one of claims 1 to 5, wherein the end faces of the parallel legs are planar and perpendicular to the length of the parallel legs.

7. A hot rolled parallel leg channel as claimed in any one of claims 1 to 5, wherein the angle between the end face of the parallel leg and the height of the breast plate is greater than 0 °.

8. A hot-rolled parallel leg channel steel as claimed in any one of claims 1 to 5, wherein the end portions of the parallel legs are provided with a first end face and a second end face, the first end face and the second end face are distributed in a V-shape, the included angle between the first end face and the height of the waist plate is greater than 0 degree, and the included angle between the second end face and the height of the waist plate is greater than 0 degree.

9. The production method of a hot rolled parallel leg channel steel as claimed in any one of claims 1 to 8, comprising the steps of: smelting, continuous casting, blank heating, cogging rolling and universal rolling.

10. The method of claim 9, wherein in the universal rolling step, the product is rolled using UR/E/UF rolling mills or UR/E/UR/UF rolling mills in sequence.

Background

At present, box-type columns are generally formed by assembling and welding four steel plates, and four welding seams exist on four edges. If two hot rolling parallel leg channel steels are adopted and the leg ends are in butt welding, the number of welding seams of the box type column can be reduced to two, the edge with complex stress does not have a poker welding seam, and the edge is internally provided with a fillet, so that the box type column has great advantages in service safety, manufacturing economy and the like.

According to the size requirement of the box-type column, the side length of each column is not less than 300mm, and the thickness of each column is not less than 20 mm. In domestic and foreign standards and current markets, hot-rolled channel steel products mainly comprise oblique leg channel steel with certain inclination on the inner side wall of a leg, and the thickness of the hot-rolled channel steel products along the length direction of the leg is variable (the leg end is thinnest); the existing parallel leg channel steel without inclination at the inner side of the leg has the waist height to leg length ratio exceeding 3:1 and the waist thickness and leg thickness both not exceeding 20mm for the specification of the height exceeding 300mm, and the existing channel steel product cannot be used for manufacturing box-type columns.

Hot rolled channel steel rolling methods are classified into two categories according to hole type characteristics. One method is a two-roller rolling method adopting butterfly holes, oblique rolling holes and direct rolling control, if the leg length of channel steel exceeds 80mm, the contact surface between a rolled piece and a roller is increased to increase the rolling pressure, meanwhile, the roller strength is influenced because the groove cutting of the hole pattern is too deep, the risk of roller interruption in the rolling process is greatly increased, if the inner side of the leg has no inclination (parallel leg), the difficulty of the groove cutting of an outlet hole is increased, and the roller winding accident is easy to occur. Secondly, although the problem of difficulty in separating the parallel leg channel steel outlet holes from the channel can be solved by adopting the open-hole universal rolling method, the finished product consisting of the vertical roll surface and the horizontal roll side surface and the front hole pattern of the finished product are open holes, the leg length direction is freely expanded, the control capability on the leg length dimension is limited, and the shape of the leg end is not controlled. The hot rolled channel steel for manufacturing the box column has special requirements on leg length and leg end.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a hot-rolled parallel leg channel steel, aiming at meeting the manufacturing requirement of a box column.

In order to achieve the purpose, the invention adopts the technical scheme that: the hot-rolled parallel leg channel steel comprises a waist plate and two parallel legs, wherein the height of the waist plate is 300-1000 mm.

The length of the parallel legs is 150 mm-500 mm.

The difference between the lengths of the two parallel legs is not higher than 15 mm.

The thickness of the waist plate is not less than 20 mm.

The thickness of the parallel legs is not less than 20 mm.

The end surfaces of the parallel legs are planes perpendicular to the length direction of the parallel legs.

The included angle between the end surface of the parallel leg and the height of the waist plate is larger than 0 degree.

The tip of parallel leg sets up first terminal surface and second terminal surface, and first terminal surface and second terminal surface are V-arrangement and distribute, first terminal surface with the contained angle between the height of wainscot is greater than 0, the second terminal surface with the contained angle between the height of wainscot is greater than 0.

The invention also provides a production method of the hot-rolled parallel leg channel steel, which comprises the following steps: smelting, continuous casting, blank heating, cogging rolling and universal rolling.

And in the universal rolling step, a UR/E/UF rolling mill or a UR/E/UR/UF rolling mill is used for rolling the rolled piece in sequence.

The hot-rolled parallel leg channel steel has wide specification coverage range and can meet the manufacturing requirements of wider box-type columns.

Drawings

The description includes the following figures, the contents shown are respectively:

FIG. 1 is a schematic structural view of a first hot rolled parallel leg channel;

FIG. 2 is a schematic structural view of a second hot rolled parallel leg channel;

FIG. 3 is a schematic structural view of a third hot rolled parallel leg channel;

FIG. 4 is a schematic view of UF roller grooving;

FIG. 5 is a schematic view of the E roll grooving;

labeled as: 1. a waist panel; 2. a parallel leg; 3. a first end face; 4. a second end face; 5. a first leg roll; 6. a second leg roll; 7. a first top roll; 8. a first bottom roll; 9. a second top roll; 10. a second bottom roll.

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings for a purpose of helping those skilled in the art to more fully, accurately and deeply understand the inventive concept and technical solution of the present invention and to facilitate its implementation.

It should be noted that, in the following embodiments, the "first" and "second" do not represent an absolute distinction relationship in structure and/or function, nor represent a sequential execution order, but merely for convenience of description.

As shown in fig. 1 to 3, the invention provides a hot-rolled parallel leg channel steel, which comprises a waist plate and two parallel legs, wherein the waist plate and the two parallel legs are formed into an integrated structure through hot rolling. The length directions of the two parallel legs are parallel, the two parallel legs are respectively fixedly connected with the two ends of the waist plate, the length directions of the parallel legs are perpendicular to the height direction of the waist plate, the height H of the waist plate is 300-1000 mm, and the range of the H/B value of the ratio of the height of the waist plate to the length of the parallel legs is 1.0-2.0. The height H of the waist board is the distance between the outer side surfaces of the two parallel legs, and the outer side surfaces of the two parallel legs are parallel.

Specifically, the height H of the waist plate is set to be 300 mm-1000 mm, and if the height H of the waist is lower than 300mm, the basic condition for manufacturing the box column is not satisfied. If the waist height H value is higher than 1000mm, the leg length B value will exceed 500mm according to the control range of the waist height to leg length ratio, and an ultra-high blank is needed, which is not feasible in the technical aspect at present. If the H/B value of the waist over leg length ratio is higher than 2.0, the basic conditions for manufacturing the box column are not satisfied.

As shown in fig. 1 to 3, the length B of the parallel legs is 150mm to 500mm, and the difference between the lengths of the two parallel legs is not more than 15 mm. If the leg length B value is less than 150mm, the basic condition for manufacturing the box column is not satisfied. If the leg length B is higher than 500mm, the technical feasibility is achieved for the same reason. If the difference between the B values of the leg lengths on the two sides is higher than 15mm, the leg ends cannot be directly butt-welded, and the defect of the difference between the leg lengths needs to be eliminated through processing, so that the economy and convenience of the product in manufacturing the box column are damaged.

As shown in fig. 1 to 3, the thickness tw of the waist panel is not less than 20mm, and the thickness direction of the waist panel is parallel to the length direction of the parallel legs. If the waist thickness tw is less than 20mm, the basic conditions for manufacturing the box column are not satisfied.

As shown in fig. 1 to 3, the thickness tf of the parallel legs is not less than 20mm, and the thickness direction of the parallel legs is parallel to the height direction of the waist panel. If the leg thickness tf is less than 20mm, the basic conditions for manufacturing the box column are not satisfied.

As shown in fig. 1, the first end surfaces of the parallel legs are planes perpendicular to the longitudinal direction of the parallel legs. The first end face is the end face of the first end of the parallel leg in the length direction, the second end of the parallel leg in the length direction is fixedly connected with the waist plate, and the first end and the second end are opposite ends of the parallel leg in the length direction.

As shown in fig. 2, as a modified embodiment, the angle α 1 between the first end surface of the parallel leg and the height of the waist panel is greater than 0 °, the first end surface is a slanted plane, and the angle between the first end surface and the length direction of the parallel leg is 90 ° - α 1. The first end face is the end face of the first end of the parallel leg in the length direction, the second end of the parallel leg in the length direction is fixedly connected with the waist plate, and the first end and the second end are opposite ends of the parallel leg in the length direction.

As shown in fig. 3, as another modified embodiment, the end portions of the parallel legs are provided with a first end surface and a second end surface, the first end surface and the second end surface are distributed in a V shape, an included angle α 1 between the first end surface and the height of the waist panel is greater than 0 °, an included angle α 2 between the second end surface and the height of the waist panel is greater than 0 °, the first end surface and the second end surface are both inclined planes, the included angle between the first end surface and the length direction of the parallel legs is 90 ° - α 1, and the included angle between the second end surface and the length direction of the parallel legs is 90 ° - α 2. The first end face and the second end face are located at the first ends of the parallel legs in the length direction, the first ends of the parallel legs are of V-shaped structures, the second ends of the parallel legs in the length direction are fixedly connected with the waist board, and the first ends and the second ends are opposite ends of the parallel legs in the length direction. The first end face is connected with the outer side face and the second end face of the parallel leg, the second end face is connected with the inner side face and the first end face of the parallel leg, and the outer side face and the inner side face of the parallel leg are opposite side faces in the thickness direction of the parallel leg.

If the H/B value of the waist length to leg length ratio is lower than 1.0, the leg length is larger than the waist height, and the hot rolling technical condition is not met.

If the leg end is in a shape with single-sided inclination or double-sided inclination, the included angle alpha 1 and alpha 2 are lower than 0 degree, and the groove shape required by the subsequent manufacturing of the box column cannot be obtained.

The invention also provides a production method of the hot-rolled parallel leg channel steel, which comprises the following steps: converter smelting or electric furnace smelting, rectangular billet or slab or beam blank continuous casting, billet heating, cogging rolling, universal rolling and air cooling.

The method for producing hot-rolled parallel leg channel steel of the present invention may further comprise the steps of: molten iron pretreatment, argon blowing refining, external refining and vacuum refining. The molten iron pretreatment step is arranged before the converter smelting or electric furnace smelting step, the argon blowing refining step is arranged between the converter smelting or electric furnace smelting step and the external refining step, the external refining step is arranged between the argon blowing refining step and the vacuum refining step, the vacuum refining step is arranged between the external refining step and the rectangular blank or plate blank or special-shaped blank continuous casting step, and the molten iron pretreatment, argon blowing refining, external refining and vacuum refining steps can be selected according to different product performances and processing process requirements, and the rest are the steps which must be adopted by the invention.

The production method of the hot-rolled parallel leg channel steel needs to adopt a rectangular blank, a plate blank or a special-shaped blank, and the blank production in a steel area can be carried out according to the existing method.

The production method of the hot-rolled parallel leg channel steel needs cogging rolling, and the hole pattern design and the procedure design are carried out according to the existing method, so that the size of an intermediate billet required by universal rolling is ensured.

The production method of the hot-rolled parallel leg channel steel needs universal rolling. In the step of universal rolling, a UR/E/UF rolling mill or a UR/E/UR/UF rolling mill is used for rolling rolled pieces in sequence, and a UR-E-UF or UR-E-UR-UF mode is used for rolling. At present, hot-rolled parallel leg channel steel is produced only by two-roller cogging rolling without adopting universal rolling, and the method has no feasibility in the technical aspect, so that the process is necessary in the universal rolling.

If the thickness of the waist plate of the intermediate billet obtained in the cogging rolling step and the thickness of the parallel legs are close to the required size of the finished product of the hot-rolled parallel leg channel steel, the universal rolling step can be used for carrying out single-pass rolling by using a UR/E/UF rolling mill or a UR/E/UR/UF rolling mill in sequence. The length and leg end shape of the parallel legs are controlled by notching on the first bottom roll of the UF rolling mill, namely notching in the RHGB area shown in figure 2, and the notching shape is designed according to the requirements of the finished product; the rolls of UR mills and E mills do not need to be grooved.

As shown in fig. 2, the first top roll and the first bottom roll are horizontal rolls, and are respectively arranged at the bottom and the top of the rolled piece. The first leg roller and the second leg roller are vertical rollers and are respectively arranged on two sides of a rolled piece; the horizontal roller is used for rolling the waist plate, the vertical roller is used for rolling the parallel legs, and the first leg roller, the second leg roller, the first bottom roller and the first top roller form a pass.

If the thickness of the waist plate of the intermediate billet obtained by cogging rolling and the thickness of the parallel legs are far larger than the finished product required size of the hot-rolled parallel leg channel steel, the rolled piece can be rolled back and forth by using a UR/E/UF rolling mill in sequence in the universal rolling step, the length of the parallel legs and the shape of the leg ends are controlled by the notch grooves on the second bottom roller of the E rolling mill, namely the notch grooves in the GB area shown in figure 3 are designed, the shapes of the notch grooves are designed according to the finished product requirements, and the second top roller and the second bottom roller are horizontal rollers and are respectively arranged at the bottom and the top of the rolled piece; the other rollers do not need to be grooved.

As a deformation implementation scheme, the thickness of the waist plate and the thickness of the parallel legs of an intermediate billet obtained by cogging rolling are far larger than the required size of a finished product of a hot-rolled parallel leg channel steel, and in the step of universal rolling, a UR/E/UR rolling mill is used for carrying out reciprocating rolling on a rolled piece in sequence, and then a UF rolling mill is used for carrying out single-pass rolling on the rolled piece. The length and leg end shape of the parallel legs are controlled by the notches on the lower horizontal roll of the E mill and also by the notches on the lower horizontal roll of the UF mill, as shown in fig. 2.

If a UF or E grooving roller is not adopted, metal on two sides of the leg is freely expanded, the leg length B value of the parallel leg, the difference between the leg lengths of the two parallel legs and the shape of the leg end cannot be effectively controlled, hot-rolled parallel leg channel steel for butt welding of the leg end cannot be directly obtained, additional processing is needed to eliminate defects, and the economical efficiency and convenience in manufacturing the box column are damaged due to the fact that materials are selected for butt welding.

In addition, when the UF rolling mill only carries out single-pass rolling, grooving of a lower horizontal roller is a good choice; if the UF rolling mill participates in the reciprocating rolling, notching the lower roller of the E rolling mill is a better choice.

The production method of the hot-rolled parallel leg channel steel can adapt to a cogging rolling process adopting rectangular billets, plate blanks and special billets, and can stably produce the large-thickness long-leg hot-rolled parallel leg channel steel only by notching the lower horizontal roller of a UF rolling mill or the lower roller of an E rolling mill according to the requirements of finished products in a universal rolling stage according to the size of an intermediate billet and rolling procedures without large adjustment of other procedures.

Example one

As shown in Table 1, the height H of the waist panel was 300mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 2mm, the length B of one of the parallel legs was 150mm, the length B of the other parallel leg was 152mm, the thickness tw of the waist panel was 20mm, the thickness tf of the parallel legs was 20mm, and α 1 was 30 °.

Example two

As shown in table 1, the height H of the waist panel was 300mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 1.0, the difference between the lengths of the two parallel legs was 3mm, the length B of one of the parallel legs was 300mm, the length B of the other parallel leg was 297mm, the thickness tw of the waist panel was 30mm, the thickness tf of the parallel leg was 30mm, and the first end surfaces of the parallel legs were planes perpendicular to the length direction of the parallel legs.

EXAMPLE III

As shown in Table 1, the height H of the waist panel was 400mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 4mm, the length B of one of the parallel legs was 200mm, the length B of the other parallel leg was 204mm, the thickness tw of the waist panel was 25mm, the thickness tf of the parallel legs was 25mm, and α 1 was 45 °.

Example four

As shown in Table 1, the height H of the waist panel was 500mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 1.7, the difference between the lengths of the two parallel legs was 4mm, the length B of one of the parallel legs was 300mm, the length B of the other parallel leg was 304mm, the thickness tw of the waist panel was 30mm, the thickness tf of the parallel legs was 30mm, and α 1 was 45 °.

EXAMPLE five

As shown in table 1, the height H of the waist panel was 500mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 1.0, the difference between the lengths of the two parallel legs was 5mm, the length B of one of the parallel legs was 500mm, the length B of the other parallel leg was 495mm, the thickness tw of the waist panel was 60mm, the thickness tf of the parallel legs was 60mm, α 1 was 45 °, α 2 was 45 °.

EXAMPLE six

As shown in Table 1, the height H of the waist panel was 600mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 5mm, the length B of one of the parallel legs was 300mm, the length B of the other parallel leg was 305mm, the thickness tw of the waist panel was 40mm, the thickness tf of the parallel legs was 40mm, and α 1 was 50 °.

EXAMPLE seven

As shown in Table 1, the height H of the waist panel was 700mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 9mm, the length B of one of the parallel legs was 350mm, the length B of the other parallel leg was 359mm, the thickness tw of the waist panel was 50mm, the thickness tf of the parallel legs was 50mm, and α 1 was 50 °.

Example eight

As shown in Table 1, the height H of the waist panel was 800mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 8mm, the length B of one of the parallel legs was 400mm, the length B of the other parallel leg was 408mm, the thickness tw of the waist panel was 50mm, the thickness tf of the parallel legs was 50mm, and α 1 was 45 °.

Example nine

As shown in Table 1, the height H of the waist panel was 900mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 11mm, the length B of one of the parallel legs was 450mm, the length B of the other parallel leg was 461mm, the thickness tw of the waist panel was 80mm, the thickness tf of the parallel legs was 80mm, α 1 was 70 °, α 2 was 70 °.

Example ten

As shown in table 1, the height H of the waist panel was 900mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 1.8, the difference between the lengths of the two parallel legs was 12mm, the length B of one of the parallel legs was 500mm, the length B of the other parallel leg was 512mm, the thickness tw of the waist panel was 60mm, the thickness tf of the parallel legs was 60mm, α 1 was 50 °, α 2 was 50 °.

EXAMPLE eleven

As shown in table 1, the height H of the waist panel was 1000mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 10mm, the length B of one of the parallel legs was 500mm, the length B of the other parallel leg was 510mm, the thickness tw of the waist panel was 60mm, the thickness tf of the parallel legs was 60mm, α 1 was 60 °, α 2 was 60 °.

Example twelve

As shown in table 1, the height H of the waist panel was 1000mm, the ratio H/B of the height of the waist panel to the length of the parallel legs was 2.0, the difference between the lengths of the two parallel legs was 14mm, the length B of one of the parallel legs was 500mm, the length B of the other parallel leg was 514mm, the thickness tw of the waist panel was 80mm, the thickness tf of the parallel legs was 80mm, α 1 was 70 °, α 2 was 70 °.

TABLE 1 examples

The invention is described above with reference to the accompanying drawings. It is to be understood that the specific implementations of the invention are not limited in this respect. Various insubstantial improvements are made by adopting the method conception and the technical scheme of the invention; the present invention is not limited to the above embodiments, and can be modified in various ways.