Special-shaped F-shaped steel, production line and production method

Abstract

The present invention provides a special-shaped F-shaped steel, a production line and a production method. The special-shaped F-shaped steel includes a web, an inner flange and an outer flange, the middle part of the outer flange is connected to one end of the web, the two ends of the outer flange are respectively located outside the two sides of the web and extend in a direction away from the web, one end of the inner flange is connected to one side of the web, and the other end of the inner flange extends in a direction away from the web. The use of special-shaped F-shaped steel to make a forklift mast can effectively improve the rigidity of the mast, improve the welding quality of the mast connectors and various accessories with the mast, and improve the safety of the entire mast. Compared with the existing production method and production line of steel sections for forklift masts, the production line and production method adopted by the technical solution of the present invention greatly reduce tooling investment and save production costs.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical manufacturing and metal material processing and forming, and in particular to a special-shaped F-shaped steel, a production line and a production method. Background Art

[0002] The forklift mast is welded from steel plates or hot-rolled steel. The commonly used mast steels include C-type, J-type and H-type, which are combined in the form of CC, CJ, HH, etc. They are used as the sliding track of the forklift system and fix various accessories. Taking the three-stage forklift mast as an example, the entire mast system consists of a three-section telescopic device consisting of an outer mast, a middle mast and an inner mast. When the mast is lifted, the fork frame moves along the inner mast, the inner mast moves along the middle mast, and the middle mast moves along the outer mast. When the forklift mast is made of F-type steel, the dimensional accuracy, strength and welding performance of the F-type steel are particularly important to the quality of the entire forklift mast.

[0003] At present, the steel sections used in domestic forklift masts are basically C-type, J-type and H-type. The mast connectors and various accessories required for the mast lifting system are welded to the surface of the steel section by flat welding or cutting and welding. The welding quality and difficulty are high. The use of F-type steel to produce forklift masts can improve the rigidity of the mast system. Therefore, an F-type steel is needed that is easy to weld firmly with various connectors and accessories. Summary of the invention

[0004] The object of the present invention is to provide a special-shaped F-shaped steel and a production line and a production method. The rolling mill on the production line can use an ordinary rolling mill, and there is no need to use a high-power rolling mill. The special-shaped F-shaped steel for the forklift gantry obtained by the production method can effectively improve the rigidity of the gantry, improve the welding quality of the gantry connecting parts and various accessories and the gantry, and improve the safety of the entire gantry.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A special-shaped F-shaped steel, which is used for a forklift door frame. The special-shaped F-shaped steel includes a web, an inner flange and an outer flange. The middle part of the outer flange is connected to one end of the web, the two ends of the outer flange are respectively located outside the two sides of the web and extend away from the web, one end of the inner flange is connected to one side of the web, and the other end of the inner flange extends away from the web.

[0007] Furthermore, in the above-mentioned special-shaped F-shaped steel, the center line of the outer flange is perpendicular to the center line of the web, the center line of the inner flange is perpendicular to the center line of the web, and the center line of the outer flange is parallel to the center line of the inner flange; preferably, the web, the inner flange and the outer flange are an integral structure.

[0008] Furthermore, in the above-mentioned special-shaped F-shaped steel, the thickness t1 of the outer flange is 20mm~30mm; the thickness t2 of the inner flange is 20mm~30mm; the thickness b2 of the web is 12mm~20mm, the width of the outer flange is b1, (b1-b2) / 2=48mm~68mm, and the width b3 of the inner flange is 48mm~68mm; the overall height h1 of the special-shaped F-shaped steel is 172mm~210mm.

[0009] Furthermore, in the above-mentioned special-shaped F-shaped steel, the thickness t1 of the outer flange is equal to the thickness t2 of the inner flange; preferably, the lengths of the two ends of the outer flange extending to the left and right sides of the web are respectively equal to the width b3 of the inner flange.

[0010] Furthermore, in the above-mentioned special-shaped F-shaped steel, the web includes an inner web and an outer web, the web between the inner flange and the outer flange is the inner web, and the web between the inner flange and the other end of the web is the outer web; the vertical distance h3 between the inner flange and the other end of the web is not greater than the vertical distance h2 between the inner flange and the outer flange, and the vertical distance h3 between the inner flange and the other end of the web is not greater than the width b3 of the inner flange and not less than the thickness b2 of the web; preferably, the vertical distance h3 between the inner flange and the other end of the web is 12 mm to 68 mm.

[0011] Furthermore, in the above-mentioned special-shaped F-shaped steel, the outer flange, the inner web and the inner flange together form a groove; the connection between the outer flange and the inner web located in the groove, the connection between the inner flange and the inner web located in the groove, and the connection between the inner flange and the outer web are all provided with bosses; the boss is a right-angled triangle structure, one right-angled side of the right-angled triangle coincides with the web, and the other right-angled side coincides with the inner flange or the outer flange; preferably, the width f of the boss is 15 mm, and the height e of the boss 4 is 5 mm; preferably, the vertical distance h2 between the inner flange and the outer flange is 120 mm to 125 mm.

[0012] Furthermore, in the above-mentioned special-shaped F-shaped steel, one vertex of the hypotenuse of the boss is connected to the inner flange or the outer flange through a transition arc R6 with a radius of 5 mm, and the center of the circle is located outside the special-shaped F-shaped steel; another vertex of the hypotenuse of the boss is connected to the web through a transition arc R7 with a radius of 5 mm, and the center of the circle is located outside the special-shaped F-shaped steel.

[0013] Furthermore, in the above-mentioned special-shaped F-shaped steel, arc transition is adopted at each intersection of the special-shaped F-shaped steel, the transition arc radius R1 at the intersection below the left end of the outer flange is 2mm, and the center is located inside the outer flange; the transition arc radius R2 at the intersection above the left end of the outer flange is 4mm, and the center is located inside the outer flange; the transition arc radius R3 at the intersection between the left end of the outer flange and the web is 4mm, and the center is located outside the special-shaped F-shaped steel; the transition arc radius R4 at the intersection above the right end of the outer flange is 4mm, and the center is located inside the outer flange; the transition arc radius R5 at the intersection above the right end of the outer flange is 4mm, and the center is located inside the outer flange; The transition arc radius R5 at the angle below the right end of the edge is 2mm, and the center is located inside the outer flange; the transition arc radius R8 at the angle above the other end of the inner flange is 2mm, and the center is located inside the inner flange; the transition arc radius R9 at the angle below the other end of the inner flange is 4mm, and the center is located inside the inner flange; the transition arc radius R10 at the angle of the lower end of the web close to the inner flange is 2mm, and the center is located inside the web; the transition arc radius R11 at the angle of the lower end of the web away from the inner flange is 4mm, and the center is located inside the web.

[0014] On the other hand, a production line for special-shaped F-shaped steel is provided, which is used to produce the above-mentioned special-shaped F-shaped steel, and the production line includes a reversible blanking machine and a universal finishing mill arranged behind the reversible blanking machine, wherein: the reversible blanking machine is used to roll the blank to roll out the F-shaped asymmetric rolled product required to enter the universal finishing mill, and the universal finishing mill rolls the F-shaped asymmetric rolled product to obtain the special-shaped F-shaped steel, and the special-shaped F-shaped steel is used to make the forklift door frame; the reversible blanking machine includes a plurality of asymmetric hole types, and the asymmetric hole types are hole types that are asymmetric both up and down and left and right; the universal finishing mill includes two universal finishing mills U1, U2 and two edge rolling mills E1, E2, and the arrangement order is U1, E1, U2, E2.

[0015] On the other hand, a method for producing special-shaped F-shaped steel is provided, wherein the special-shaped F-shaped steel is produced by using the above-mentioned production line, and the method comprises the following steps:

[0016] Step 1: rolling the billet using a reversible billet opening machine to produce an F-shaped asymmetric rolled piece required for entering a finishing mill;

[0017] Step 2, rolling the F-shaped asymmetric rolled piece obtained in step 1 by rolling mills U1, E1, U2 and E2 in sequence to obtain the heterogeneous F-shaped steel for the forklift gantry;

[0018] In the step 2, the horizontal reduction of the U1 horizontal roller is 1mm-2mm, and the reduction of the U1 vertical roller is 4mm-7mm; the reduction of the E1 is 5mm-10mm; the horizontal reduction of the U2 horizontal roller is 1mm-4mm, and the reduction of the U2 vertical roller is 3mm-6mm; the reduction of the E2 is 5mm-8mm.

[0019] Analysis shows that a special-shaped F-shaped steel and production line and production method, the special-shaped F-shaped steel includes a web, an inner flange and an outer flange, the dimensional accuracy, strength and welding performance of the above-mentioned F-shaped steel can meet the requirements of making a forklift mast. Using special-shaped F-shaped steel to make a forklift mast can effectively improve the rigidity of the mast, improve the welding quality of the mast connector and various accessories and the mast, and improve the safety of the entire mast.

[0020] Compared with the use of C-shaped steel, J-shaped steel or H-shaped steel to make forklift masts, the outer web designed by the special-shaped F-shaped steel of the present invention can effectively improve the rigidity of the mast, while ensuring the welding quality of the mast connectors and various accessories, and improving the overall safety of the forklift mast. F-shaped steel is easy to be firmly welded with various connectors and various accessories, and the use of F-shaped steel to produce forklift masts can improve the rigidity of the mast system.

[0021] Compared with the prior art, the production line and production method adopted by the technical solution of the present invention have greatly reduced tooling investment and saved production costs compared with the existing production method and production line of steel sections for forklift masts; at the same time, the new type of special-shaped F-shaped steel for forklift masts produced by this method is formed by hot rolling, and the designed outer web can effectively improve the rigidity of the mast, while ensuring the welding quality of the mast connectors and various accessories, thereby improving the overall safety of the forklift mast. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0023] Figure 1 A cross-sectional view of a special-shaped F-shaped steel according to an embodiment of the present invention.

[0024] Figure 2 Another cross-sectional view of a special-shaped F-shaped steel according to an embodiment of the present invention.

[0025] Figure 3 A roller diagram of a reversible blanking machine according to an embodiment of the present invention.

[0026] Figure 4 Schematic diagram of the pass profiles of the universal finishing mills U1 and U2 according to an embodiment of the present invention.

[0027] Figure 5Schematic diagram of the pass profiles of edge rolling machines E1 and E2 according to an embodiment of the present invention.

[0028] Description of reference numerals: 1 web; 2 inner flange; 3 outer flange; 4 boss; 5 groove; 6 box-shaped hole; 7 first asymmetric deep cut hole; 8 second asymmetric deep cut hole; 9 first asymmetric control hole; 10 second asymmetric control hole;

[0029] h1 Overall height of the F-shaped steel; h2 Vertical distance between the inner flange and the outer flange; h3 Vertical distance between the inner flange and the other end of the web; t1 Thickness of the outer flange; t2 Thickness of the inner flange; b1 Width of the outer flange; b2 Thickness of the web; b3 Width of the inner flange; e Height of the boss; f Width of the boss;

[0030] R1 is the transition arc radius at the intersection below the left end of the outer flange; R2 is the transition arc radius at the intersection above the left end of the outer flange; R3 is the transition arc radius at the intersection between the left end of the outer flange and the web; R4 is the transition arc radius at the intersection above the right end of the outer flange; R5 is the transition arc radius at the intersection below the right end of the outer flange; R6 is the transition arc radius at the connection between one vertex of the hypotenuse of the boss 4 and the inner flange or the outer flange; R7 is the transition arc radius at the connection between the other vertex of the hypotenuse of the boss 4 and the web; R8 is the transition arc radius at the intersection above the free end of the inner flange; R9 is the transition arc radius at the intersection below the free end of the inner flange; R10 is the transition arc radius at the intersection of the lower end of the web near the inner flange; R11 is the transition arc radius at the intersection of the lower end of the web away from the inner flange;

[0031] α is the angle between the outer flange and the web; β is the angle between the inner flange and the web. DETAILED DESCRIPTION

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention and does not limit the present invention. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as a part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present invention encompasses such modifications and variations within the scope of the appended claims and their equivalents.

[0033] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected", "connected" and "set" used in the present invention should be understood in a broad sense. For example, they can be fixedly connected or detachably connected; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0034] In the description of the present invention, the inner flange 2 is located on the "right" side of the web 1, the side opposite to the "right" side is the "left" side, the end of the web 1 of the special-shaped F-shaped steel close to the outer flange 3 is the "upper", and the other end of the web 1 is the "lower".

[0035] like Figures 1 to 5 As shown, according to an embodiment of the present invention, a special-shaped F-shaped steel is provided. The special-shaped F-shaped steel is used to make a forklift door frame, such as Figure 1 As shown, the special-shaped F-shaped steel includes a web 1, an inner flange 2 and an outer flange 3. The middle part of the outer flange 3 is connected to one end of the web 1, and both ends of the outer flange 3 are free ends. The two ends of the outer flange 3 are respectively located outside the two sides of the web 1 and extend in a direction away from the web 1. One end of the inner flange 2 is connected to one side of the web 1, and the other end of the inner flange 2 extends in a direction away from the web 1. The other end of the inner flange 2 is a free end.

[0036] Furthermore, the centerline of the outer flange 3 is perpendicular to the centerline of the web 1, the centerline of the inner flange 2 is perpendicular to the centerline of the web 1, and the centerline of the outer flange 3 is parallel to the centerline of the inner flange 2; the inner flange 2 and the outer flange 3 are both perpendicular to the web 1, that is, the angle α between the outer flange 3 and the web 1 is 90°, and the angle β between the inner flange 2 and the web 1 is 90°. Figure 1 Such arrangement facilitates the assembly of the special-shaped F-shaped steel. Preferably, the web 1, the inner flange 2 and the outer flange 3 are an integrated structure.

[0037] Furthermore, if Figure 2As shown in the figure, the specifications of the special-shaped F-shaped steel are as follows: the thickness t1 of the outer flange 3 and the thickness t2 of the inner flange 2 are both 20mm~30mm (for example: 20mm, 20.8mm, 21.6mm, 22.4mm, 23.2mm, 24mm, 24.8mm, 25mm, 25.6mm, 26.4mm, 27.2mm, 28mm, 28.8mm, 29.6mm, 30mm), and the accuracy requirement is ±0.8mm; the width of the outer flange 3 is b1, and the thickness b2 of the web 1 is 12mm~20mm (for example: 12mm, 12.8mm, 13.6mm, 14.4mm, 15.2mm, 16mm, 16.8mm, 17.6mm, 18.4mm, 19.2mm, 20mm), and the accuracy requirement is ±0.8 mm, the lengths of the two ends of the outer flange 3 extending to the left and right sides of the web 1 are (b1-b2) / 2=48mm~68mm (for example: 48mm, 49mm, 50mm, 52mm, 54mm, 56mm, 57mm, 59mm, 62mm, 64mm, 66.2mm, 67mm, 68mm), with an accuracy requirement of ±1.0mm; the width b3 of the inner flange 2 is 48mm~68mm (for example: 48mm, 49mm, 50mm, 52mm, 54mm, 56mm, 57mm, 59mm, 62mm, 64mm, 66.2mm, 67mm, 68mm), with an accuracy requirement of ±1.0mm; the lengths of the two ends of the outer flange 3 extending to the left and right sides of the web 1 are equal to the width b3 of the inner flange 2. The vertical distance h2 between the inner flange 2 and the outer flange 3 (i.e., the height in the groove 5) is 120mm to 125mm (e.g., 120mm, 120.5mm, 121mm, 121.5mm, 122mm, 122.5mm, 123mm, 123.5mm, 123.8mm, 124mm, 124.5mm, 124.8mm, 125mm), with an accuracy requirement of ±0.8mm. The vertical distance h3 between the inner flange 2 and the other end of the web 1 (the height of the outer web) is 12mm to 68mm (e.g., 12mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 68mm), with an accuracy requirement of ±1.0mm. The vertical distance h3 between the inner flange 2 and the other end of the web 1 is not greater than the vertical distance h2 between the inner flange 2 and the outer flange 3. The vertical distance h3 between the inner flange 2 and the other end of the web 1 should be no greater than the width b3 of the inner flange 2 and no less than the thickness b2 of the web 1, so as to improve the overall stability of the special-shaped F-shaped steel. The overall height h1 of the special-shaped F-shaped steel is 172mm to 210mm (for example: 172mm, 175mm, 180mm, 185mm, 190mm, 195mm, 200mm, 205mm, 210mm).

[0038] Furthermore, the web 1 includes an inner web and an outer web, the web between the inner flange 2 and the outer flange 3 is the inner web, and the web between the inner flange 2 and the other end of the web 1 is the outer web. The outer flange 3, the inner web and the inner flange 2 together form a groove 5. The height of the outer web is not greater than the height of the groove, and the widths of the inner flange 2 and the outer flange 3 on the same side of the web 1 are the same, that is, the vertical distances between the free ends of the inner flange 2 and the free ends of the outer flange 3 and the web 1 are equal.

[0039] like Figure 1 As shown, bosses 4 are provided at the connection between the outer flange 3 and the inner web located in the groove 5, at the connection between the inner flange 2 and the inner web located in the groove 5, and at the connection between the inner flange 2 and the outer web, that is, three bosses 4 are provided on the same side of the web 1, and the three bosses 4 are all provided on the side of the web 1 connected to the inner flange 2. The boss 4 is a right triangle structure, one right angle side of the right triangle coincides with the web 1, and the other right angle side coincides with the inner flange 2 or the outer flange 3. The width f of the boss 4 (the length of one right angle side of the right triangle, which is parallel to the center line of the web 1) is 15 mm, and the height e of the boss 4 (the length of the other right angle side of the right triangle, which is perpendicular to the center line of the web 1) is 5 mm. One vertex of the hypotenuse of the boss 4 is connected to the inner flange 2 or the outer flange 3 through a transition arc, and the transition arc radius R6 at the connection is 5 mm, and the center of the circle is located outside the special-shaped F-shaped steel. The other vertex of the hypotenuse of the boss 4 is connected to the web 1 through a transition arc, and the transition arc radius R7 at the connection is 5 mm, and the center of the circle is located outside the special-shaped F-shaped steel. The setting of the boss 4 facilitates the installation of accessories for the special-shaped F-shaped steel, and improves the overall stability of the special-shaped F-shaped steel and the forklift gantry.

[0040] like Figure 2As shown, arc transition is adopted at each intersection of the special-shaped F-shaped steel. The transition arc radius R1 at the intersection below the left end of the outer flange 3 is 2 mm, and the center is located inside the outer flange 3. The transition arc radius R2 at the intersection above the left end of the outer flange 3 is 4 mm, and the center is located inside the outer flange 3. The transition arc radius R3 at the intersection between the left end of the outer flange 3 and the web is 4 mm, and the center is located outside the special-shaped F-shaped steel. The transition arc radius R4 at the intersection above the right end of the outer flange 3 is 4 mm, and the center is located inside the outer flange 3. The transition arc radius R5 at the intersection below the right end of the outer flange 3 is 4 mm, and the center is located inside the outer flange 3. The arc radius R5 is 2mm, and the center is located inside the outer flange 3; the transition arc radius R8 at the angle above the other end of the inner flange 2 (the free end of the inner flange 2) is 2mm, and the center is located inside the inner flange 2; the transition arc radius R9 at the angle below the other end of the inner flange 2 is 4mm, and the center is located inside the inner flange 2; the transition arc radius R10 at the angle of the lower end of the web 1 close to the inner flange 2 is 2mm, and the center is located inside the web 1; the transition arc radius R11 at the angle of the lower end of the web 1 away from the inner flange 2 is 4mm, and the center is located inside the web 1. Each angle is used for rolling hole design, and there is no accuracy requirement. See Figure 1 , the above specifications of special-shaped F-shaped steel are convenient for assembly.

[0041] The present invention also discloses a production line for special-shaped F-shaped steel, which is used to produce the above-mentioned special-shaped F-shaped steel. The production line includes a reversible blanking machine and a universal finishing mill set arranged behind the reversible blanking machine. The rolling mills in the reversible blanking machine and the universal finishing mill set are both ordinary rolling mills, wherein: the reversible blanking machine is used to roll the blank to roll out the F-shaped asymmetric rolled piece required to enter the universal finishing mill set, and the universal finishing mill set rolls the F-shaped asymmetric rolled piece to obtain the special-shaped F-shaped steel, which is used to make forklift door frames; the reversible blanking machine includes a plurality of asymmetric hole types, and the asymmetric hole types are hole types that are asymmetric both up and down and left and right; the universal finishing mill set includes two universal finishing mills U1, U2 and two edge rolling mills E1, E2, and the arrangement order is U1, E1, U2, E2.

[0042] In order to ensure the asymmetry of the finished product of the special-shaped F-shaped steel, each hole profile is an asymmetric hole profile, that is, each rolling mill in the reversible billet opening machine and the universal finishing mill group adopts an asymmetric hole profile to ensure different elongation rates on both sides.

[0043] The reversible blanking machine is used to roll the blank to roll out the F-type asymmetric rolled product required for entering the universal finishing mill; then the U1, E1, U2, and E2 rolling mills of the universal finishing mill are used to roll the F-type asymmetric rolled product in sequence to obtain special-shaped F-shaped steel for forklift masts.

[0044] Furthermore, the reversible blanking machine also includes a box-type hole type, which can roll the blank into an asymmetric blank that meets the size specifications. The asymmetric hole type of the reversible blanking machine also includes an asymmetric cutting depth hole and an asymmetric control hole, in order to achieve the maximum asymmetric deformation in the reversible blanking machine. The reversible blanking machine is sequentially arranged with 1 to 4 box-type holes, 2 to 4 asymmetric cutting depth holes, and 2 to 3 asymmetric control holes. Preferably, as Figure 3 As shown, the reversible blanking machine is arranged with 1 box-shaped hole, 2 asymmetric deep cutting holes, and 2 asymmetric control holes, which are box-shaped hole 6, first asymmetric deep cutting hole 7, second asymmetric deep cutting hole 8, first asymmetric control hole 9, and second asymmetric control hole 10. Among them, the first symmetric deep cutting hole 7 and the second asymmetric deep cutting hole 8 have a relatively large reduction, and the mill load is relatively large, while the first asymmetric control hole 9 and the second asymmetric control hole 10 have a relatively small reduction, and the mill load is relatively small. Therefore, the mill load distribution on the BD (reversible blanking machine) is uniform, and the square billet can be rolled into F-type asymmetric rolled pieces through 5 passes.

[0045] Specifically, in order to ensure the asymmetry of the finished product of the special-shaped F-shaped steel, the first asymmetric deep cut hole, the second asymmetric deep cut hole, the first asymmetric control hole and the second asymmetric control hole all adopt asymmetric hole profiles (that is, the hole profiles are different up and down and left and right), so as to ensure that the elongation rates on both sides of the special-shaped F-shaped steel are different. The hole profile of the reversible blanking machine is designed as an asymmetric hole profile, and the elongation rates of its various parts are also different, that is, the elongation rates of the hole profiles are different up and down and left and right. The purpose of such a setting is to obtain an asymmetric special-shaped F-shaped steel structure to prevent the metal from not being able to fill the hole profile, resulting in the scrapping of the product. For example, if the elongation rates of a certain hole profile are the same on the left and right, the hole profile relative to the left end of the outer flange 3 of the special-shaped F-shaped steel will be full, while the hole profile relative to the right end of the outer flange 3 and the inner flange 2 will not be full. The box-shaped hole 6 is used to roll the blank into an asymmetric blank that meets the size specifications; the first asymmetric deep cut hole 7 is a closed hole type, and its main function is to extrude the waist of the asymmetric blank after the box-shaped hole 6 is rolled into an F shape; the second asymmetric deep cut hole 8 is a closed hole type, and its main function is to further extrude the waist of the asymmetric blank and extend the length of the inner flange 2 and the outer flange 3. The first asymmetric control hole 9 is a closed hole type, and its main function is to expand the vertical distance between the inner flange 2 and the outer flange 3 (i.e., the height in the groove 5), and at the same time prevent the inner flange 2 and the outer flange 3 from being too long; the second asymmetric control hole 10 is an open hole type, and its main function is to further extrude the thickness of the web 1 and expand the vertical distance between the inner flange 2 and the outer flange 3 (the height of the inner stop of the groove 5).

[0046] Furthermore, if Figure 4 and Figure 5As shown, each mill in the universal finishing mill group U1, E1, U2, and E2 uses different roll gap values ​​on both sides (roll gap refers to the roll gap of the rolls), different reductions (reduction refers to the amount of deformation of the F-type asymmetric rolled piece after being thinned through the pass), and different elongations (elongation refers to the deformation ratio of the F-type asymmetric rolled piece after being rolled). Each mill in the universal finishing mill group uses an asymmetric pass, and the edge rolling mill is a control pass.

[0047] Furthermore, if Figure 5 As shown, the two edge rolling mills E1 and E2 are both open-pass type to compress the width of the outer flange 3 and the thickness of the web 1 of the F-type asymmetric rolled piece.

[0048] The present invention also discloses a method for producing special-shaped F-shaped steel. The method is used to produce the special-shaped F-shaped steel on the production line, and comprises the following steps:

[0049] Step 1: rolling the billet using a reversible billet opening machine to produce an F-shaped asymmetric rolled piece required for entering a finishing mill;

[0050] Step 2: rolling the F-shaped asymmetric rolled piece obtained in step 1 by rolling mills U1, E1, U2 and E2 in sequence to obtain a special-shaped F-shaped steel for a forklift gantry;

[0051] In step 2, the horizontal reduction of the U1 horizontal roller is 1mm-2mm (for example, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm), the reduction of the U1 vertical roller is 4mm-7mm (for example, 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5.0mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6.0mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm); the reduction of E1 is 5mm-10mm (for example, 5mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9. The horizontal reduction of U2 horizontal roller is 1mm~4mm (for example, 1mm, 1.4mm, 1.8mm, 2.0mm, 2.4mm, 2.8mm, 3.0mm, 3.4mm, 3.8mm, 4mm), and the reduction of U2 vertical roller is 3mm~6mm (for example, 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm, 4.0mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5.0mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm); the reduction of E2 is 5mm~8mm (for example, 5mm, 5.4mm, 5.8mm, 6.0mm, 6.4mm, 6.8mm, 7.0mm, 7.4mm, 7.8mm, 8mm).

[0052] Further, in step one, the temperature of the billet when entering the reversible billet opening machine is 1180°C to 1260°C, which can be a range between any two temperatures of 1180°C, 1185°C, 1190°C, 1195°C, 1200°C, 1205°C, 1210°C, 1215°C, 1220°C, 1225°C, 1230°C, 1235°C, 1240°C, 1245°C, 1250°C, 1255°C, and 1260°C. Because the rolling of special-shaped steel is difficult, the higher the heating temperature, the better the uniformity of the billet. If the heating temperature is low, the temperature of the billet surface may be high but the temperature of the core is low, which may lead to difficulty in rolling deformation, commonly known as rolling inability. The special-shaped F-shaped steel billet of the present application has good uniformity at 1180°C to 1260°C, and rolling deformation is easier. Preferably, the temperature of the blank when entering the reversible blanking machine is 1200-1245° C. Such an arrangement can make the blank entering the reversible blanking machine have good uniformity, which is convenient for rolling.

[0053] Furthermore, in step 1, the rolling passes of the reversible blooming machine are 5 passes. The hole types of the 5 passes are box-shaped hole 6, first asymmetric deep cutting hole 7, second asymmetric deep cutting hole 8, first asymmetric control hole 9 and second asymmetric control hole 10 in sequence.

[0054] Example 1

[0055] In this embodiment, the height e of the boss 4 is 5 mm, and the width f of the boss 4 is 15 mm; each angle is used for rolling pass design, and there is no precision requirement. The transition arc radius R6 at the connection between the boss 4 and the inner flange 2 or the outer flange 3 (the transition arc radius at the connection between one vertex of the hypotenuse of the boss 4 and the inner flange 2 or the outer flange 3) is 5 mm; the transition arc radius R7 at the connection between the boss 4 and the web 1 (the transition arc radius at the connection between the other vertex of the hypotenuse of the boss 4 and the web 1) is 5 mm; the transition arc radius R5 at the intersection angle located below the right end of the outer flange 3 is 2 mm; the transition arc radius R2 at the intersection angle located above the left end of the outer flange 3 is 4 mm; the inner flange 2 and the outer flange 3 are both perpendicular to the web 1, see Figure 1 and Figure 2 , the above specifications of special-shaped F-shaped steel are convenient for assembly.

[0056] Figure 3 This is a roller diagram (hole type schematic diagram) of the reversible blanking machine of this embodiment, including a box-shaped hole 6, a first asymmetric deep cutting hole 7, a second asymmetric deep cutting hole 8, a first asymmetric control hole 9, and a second asymmetric control hole 10.

[0057] Figure 4 Schematic diagram of the pass type of the universal finishing mill of this embodiment. Each mill in the universal finishing mill group adopts an asymmetric pass type.

[0058] Figure 5 Schematic diagram of the pass type of the edge rolling machine in this embodiment. Each edge rolling machine adopts an asymmetric pass type.

[0059] The following describes the production line and production method of special-shaped F-shaped steel for forklift masts with product dimensions as shown in Table 1 and Table 2. Table 1 shows the dimension parameters of special-shaped F-shaped steel, and Table 2 shows the R angle parameters of special-shaped F-shaped steel products.

[0060] Table 1 Dimensional parameters of special-shaped F-shaped steel

[0061]

[0062] Table 2 R angle parameters of special-shaped F-shaped steel products

[0063] R angle R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 Value(mm) 2 4 4 4 2 5 5 2 4 2 4

[0064] The production line is as follows: including a reversible billet opening machine and a universal finishing mill (the universal finishing mill includes two universal finishing mills and two edge rolling mills),

[0065] The reversible blanking machine is arranged with a box-shaped hole 6, a first asymmetric deep cutting hole 7, a second asymmetric deep cutting hole 8, a first asymmetric control hole 9, and a second asymmetric control hole 10 in sequence. Each asymmetric hole type is asymmetric in the upper and lower parts and left and right parts of the rolled piece (the hole type relative to the position of the outer flange 3 is located on the upper and lower sides of the left end of each asymmetric hole type, and the hole type relative to the position of the inner flange 2 is located on the lower side of each asymmetric hole type).

[0066] The universal finishing mill group includes two universal finishing mills, U1 and U2, and two edge rolling mills, E1 and E2, and the arrangement order is U1, E1, U2, E2. Each rolling mill in the universal finishing mill group adopts an asymmetric pass type, among which the edge rolling mill is a control pass type. Since the width b1 of the outer flange 3 and the width b3 of the inner flange 2 increase greatly after passing through the U1 universal finishing mill, in order to control the change in the width of the outer flange 3 and the inner flange 2, the U1 universal finishing mill is followed by an E1 edge rolling mill to control the width of the outer flange 3 and the inner flange 2, and the E1 edge rolling mill is followed by a U2 universal finishing mill. The U2 universal finishing mill has a smaller reduction, so that the width of the outer flange 3 and the inner flange 2 changes less, in order to further control the accuracy of each size of the special-shaped F-shaped steel. The U2 is followed by an E2 edge rolling mill to control the height of the outer web.

[0067] The method of using the above production line to produce the special-shaped F-shaped steel shown in Table 1 and Table 2 is as follows:

[0068] (1) A continuous casting billet with a cross-sectional specification of 180 mm × 220 mm is heated to 1215° C. to 1250° C. in a heating furnace;

[0069] (2) The heated continuous casting square billet is sent to a reversible billet opening machine for billet opening and rolling. The rolling program of the reversible billet opening machine is shown in Table 3. After the continuous casting square billet is rolled by the reversible billet opening machine for 5 passes, the F-type asymmetric rolled product required by the finishing mill is obtained.

[0070] Table 3 Billet mill rolling program

[0071] path K1 K2 K3 K4 K5 Hole Type Box hole Deep hole cutting Deep hole cutting Control hole Control hole Height of rolled product(mm) 218 216 210 206 205 Width of outer flange of rolled product (mm) 180 165 154 140 128 Rolled product web thickness (mm) 90 58 50 32 28 Width of outer web of rolled product (mm) 54 53 45 45 40 Compression ratio (%) 22.0 21.5 33.0 31.0 25.2

[0072] (3) Then, the F-shaped asymmetric rolled piece obtained in step (2) is rolled in sequence using the U1, E1, U2, and E2 rolling mills to obtain a special-shaped F-shaped steel for a forklift gantry. The rolling procedure of the universal finishing mill is shown in Table 4.

[0073] Table 4 Rolling schedule of universal finishing mill (unit: mm)

[0074]

[0075] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0076] A special-shaped F-shaped steel and a production line and a production method, the special-shaped F-shaped steel comprises a web 1, an inner flange 2 and an outer flange 3, the dimensional accuracy, strength and welding performance of the F-shaped steel can meet the requirements for making a forklift mast. Using the special-shaped F-shaped steel to make a forklift mast can effectively improve the rigidity of the mast, improve the welding quality of the mast connector and various accessories and the mast, and improve the safety of the entire mast.

[0077] Compared with the use of C-shaped steel, J-shaped steel or H-shaped steel to make forklift masts, the outer web designed by the special-shaped F-shaped steel of the present invention can effectively improve the rigidity of the mast, while ensuring the welding quality of the mast connectors and various accessories, and improving the overall safety of the forklift mast. F-shaped steel is easy to be firmly welded with various connectors and various accessories, and the use of F-shaped steel to produce forklift masts can improve the rigidity of the mast system.

[0078] Compared with the prior art, the production line and production method adopted by the technical solution of the present invention have greatly reduced tooling investment and saved production costs compared with the existing production method and production line of steel sections for forklift masts (the prior art generally includes two blanking machines, multiple universal finishing mills and multiple edge rolling mills, exemplarily including BD1, BD2, U1, E1, U2, E2, U3, etc.); at the same time, the new special-shaped F-shaped steel for forklift masts produced by this method is hot-rolled, and the designed outer web can effectively improve the rigidity of the mast, while ensuring the welding quality of the mast connectors and various accessories, thereby improving the overall safety of the forklift mast.

[0079] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A special-shaped F-shaped steel, which is used for a forklift gantry, characterized in that: The special-shaped F-shaped steel comprises a web, an inner flange and an outer flange, wherein the middle portion of the outer flange is connected to one end of the web, the two ends of the outer flange are respectively located outside the two sides of the web and extend in a direction away from the web, one end of the inner flange is connected to one side of the web, and the other end of the inner flange extends in a direction away from the web, The center line of the outer flange is perpendicular to the center line of the web, the center line of the inner flange is perpendicular to the center line of the web, and the center line of the outer flange is parallel to the center line of the inner flange; The web, the inner flange and the outer flange are an integral structure. The thickness t1 of the outer flange is 20 mm to 30 mm; the thickness t2 of the inner flange is 20 mm to 30 mm; The thickness b2 of the web is 12 mm to 20 mm, the width of the outer flange is b1, (b1-b2) / 2=48 mm to 68 mm, and the width b3 of the inner flange is 48 mm to 68 mm; The overall height h1 of the special-shaped F-shaped steel is 172mm~210mm, The thickness t1 of the outer flange is equal to the thickness t2 of the inner flange; The lengths of the two ends of the outer flange extending to the left and right sides of the web are equal to the width b3 of the inner flange. The web plate comprises an inner web plate and an outer web plate, the web plate between the inner flange and the outer flange is the inner web plate, and the web plate between the inner flange and the other end of the web plate is the outer web plate; The vertical distance h3 between the inner flange and the other end of the web is not greater than the vertical distance h2 between the inner flange and the outer flange, and the vertical distance h3 between the inner flange and the other end of the web is not greater than the width b3 of the inner flange and not less than the thickness b2 of the web; The vertical distance h3 between the inner flange and the other end of the web is 12 mm to 68 mm. The outer flange, the inner web and the inner flange together form a groove; The connection between the outer flange and the inner web located in the groove, the connection between the inner flange and the inner web located in the groove, and the connection between the inner flange and the outer web are all provided with bosses; The boss is a right-angled triangle structure, one right-angled side of the right-angled triangle coincides with the web, and the other right-angled side coincides with the inner flange or the outer flange; The vertical distance h2 between the inner flange and the outer flange is 120 mm to 125 mm.

2. The special-shaped F-shaped steel according to claim 1, characterized in that: The width f of the boss is 15 mm, and the height e of the boss is 5 mm.

3. The special-shaped F-shaped steel according to claim 1, characterized in that: One vertex of the hypotenuse of the boss is connected to the inner flange or the outer flange through a transition arc R6 with a radius of 5 mm, and the center of the arc is located outside the special-shaped F-shaped steel; Another vertex of the hypotenuse of the boss is connected to the web via a transition arc R7 with a radius of 5 mm, and the center of the arc is located outside the special-shaped F-shaped steel.

4. The special-shaped F-shaped steel according to claim 1, characterized in that: The F-shaped steel adopts arc transition at each intersection angle, and the transition arc radius R1 at the intersection angle below the left end of the outer flange is 2mm, and the center of the circle is located inside the outer flange; The radius R2 of the transition arc located at the intersection angle above the left end of the outer flange is 4 mm, and the center of the circle is located inside the outer flange; The radius R3 of the transition arc at the intersection between the left end of the outer flange and the web is 4 mm, and the center of the circle is located outside the special-shaped F-shaped steel; The radius R4 of the transition arc at the intersection angle above the right end of the outer flange is 4 mm, and the center of the circle is located inside the outer flange; The radius R5 of the transition arc at the intersection angle below the right end of the outer flange is 2 mm, and the center of the circle is located inside the outer flange; The radius R8 of the transition arc at the intersection angle above the other end of the inner flange is 2 mm, and the center of the circle is located inside the inner flange; The radius R9 of the transition arc at the intersection angle below the other end of the inner flange is 4 mm, and the center of the circle is located inside the inner flange; The transition arc radius R10 at the intersection angle of the lower end of the web near the inner flange is 2 mm, and the center of the circle is located inside the web; The radius R11 of the transition arc at the angle between the lower end of the web and the inner flange is 4 mm, and the center of the circle is located inside the web.

5. A production line for special-shaped F-shaped steel, characterized in that: The production line is used to produce the special-shaped F-shaped steel according to any one of claims 1 to 4, and the production line comprises a reversible blanking machine and a universal finishing mill arranged behind the reversible blanking machine, wherein: The reversible blanking machine is used to roll the blank to roll out the F-shaped asymmetric rolled piece required to enter the universal finishing mill, and the universal finishing mill rolls the F-shaped asymmetric rolled piece to obtain the special-shaped F-shaped steel, which is used to make the forklift gantry; The reversible blanking machine includes a plurality of asymmetric hole types, wherein the asymmetric hole types are hole types that are asymmetric both vertically and horizontally; The universal finishing mill group includes two universal finishing mills U1 and U2 and two edge rolling mills E1 and E2, and the arrangement order is U1, E1, U2, and E2.

6. A method for producing special-shaped F-shaped steel, characterized in that: The production line according to claim 5 is used to produce the special-shaped F-shaped steel according to any one of claims 1 to 4, comprising the following steps: Step 1: rolling the billet using a reversible billet opening machine to produce an F-shaped asymmetric rolled piece required for entering a finishing mill; Step 2, rolling the F-shaped asymmetric rolled piece obtained in step 1 by rolling mills U1, E1, U2 and E2 in sequence to obtain the heterogeneous F-shaped steel for the forklift gantry; In the step 2, the horizontal reduction of the U1 horizontal roller is 1mm~2mm, and the reduction of the U1 vertical roller is 4mm~7mm; the reduction of the E1 is 5mm~10mm; the horizontal reduction of the U2 horizontal roller is 1mm~4mm, and the reduction of the U2 vertical roller is 3mm~6mm; the reduction of the E2 is 5mm~8mm.

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