Turnover method of large steel box girder

Abstract

The invention discloses a turning method of a large steel box girder, which is realized through an auxiliary tool, the outer side of the auxiliary tool is provided with an arc surface, the inner side of the auxiliary tool is provided with a mounting cavity, the auxiliary tool is provided with a first contact surface connected with a flange plate, a second contact surface connected with a web and a clamping groove connected with the first contact surface and the second contact surface, and the clamping groove is matched with an extension section of the flange plate; the turnover method comprises the following steps: (1) mounting the auxiliary tool at the top and the bottom of the steel box girder; (2) hoisting the steel box girder through hoisting equipment, and enabling the arc surface of the auxiliary tool at the bottom of the steel box girder to be connected with a bearing surface; (3) applying turnover boosting force to the steel box girder through the hoisting equipment; and (4) the hoisting point of the hoisting equipment on the steel box girder is adjusted, the top auxiliary tool of the steel box girder continues to roll 90 degrees along the bearing face, and turning over of the steel box girder is completed. According to the invention, the transport capacity can be saved, and the turnover operation can be realized by using the hoisting equipment with the hoisting tonnage greater than half of the dead weight of the steel box girder.

Description

Technical Field

[0001] The invention relates to the technical field of steel box girder processing, in particular to a method for turning over a large steel box girder. Background Art

[0002] Large steel box girders are widely used in bridge engineering, water conservancy engineering, construction, shipping, etc. As a load-bearing component of steel structure, large steel box girders have the characteristics of strong bearing capacity, good seismic performance and corrosion resistance.

[0003] The steel box girder is a box-shaped structure formed by welding the upper flange plate, the web plate and the lower flange plate. The upper flange plate and the web plate need to be welded, the lower flange plate and the web plate need to be welded, and the joints of the plates need to be welded; because the main welds are not allowed to be welded vertically or vertically, the box girder needs to be turned over as a whole during the welding process to complete the welding of the box girder. The traditional method of turning over a box girder is to lift the box girder with a lifting device to turn it over; the lifting tonnage of the lifting device must be greater than the weight of the box girder to achieve the turning operation in the air. This method is only suitable for small box girder structures with low height and light weight.

[0004] Large steel box girders are characterized by high height, long length and heavy weight. The beam is more than 3 meters high and weighs 100-150 tons. It is difficult to complete the turning and welding of steel box girders without large-tonnage lifting equipment. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for turning over a large steel box girder, which can specifically adopt the following technical solutions: The turning method of the large steel box girder of the present invention is realized by auxiliary tooling. The auxiliary tooling is provided with an arc surface on the outside, and a mounting cavity is provided on the inside of the auxiliary tooling, wherein the mounting cavity has a first contact surface connected to the flange plate, a second contact surface connected to the web plate, and a slot connecting the first contact surface and the second contact surface, wherein the slot is adapted to the extended section of the flange plate; The turning method comprises: The first step is to select a suitable number of auxiliary toolings according to the length of the steel box girder, and install the auxiliary toolings on the top and bottom of the steel box girder, wherein the arc surface of the auxiliary toolings is located above the upper flange plate and below the lower flange plate; The second step is to hoist the steel box girder by means of lifting equipment, and make the arc surface of the auxiliary tooling at the bottom of the steel box girder connect with the supporting surface; The third step is to use the lifting equipment to give the steel box girder a turning boost, so that the steel box girder rolls 90° along the supporting surface under the action of the bottom auxiliary tooling. At this time, the side of the auxiliary tooling is connected to the supporting surface, and the web of the steel box girder is located above the supporting surface; The fourth step is to adjust the lifting point of the lifting equipment on the steel box girder so that the top auxiliary tooling of the steel box girder continues to roll 90° along the supporting surface. At this time, the upper flange plate is at the bottom and the lower flange plate is at the top, completing the turning over of the steel box girder.

[0006] The web plates of the steel box girder are arranged symmetrically to the central axis of the flange plates, and the web plate spacing is smaller than the width of the flange plates.

[0007] The arc surface is symmetrically arranged along the central axis of the flange plate, and the ends of the arc surface are arranged on both sides of the web plate.

[0008] The end of the arc surface is connected with a straight section, and the straight section is arranged parallel to the web.

[0009] The auxiliary tooling is formed by welding steel plates, and the steel plates are provided with reinforcing ribs.

[0010] The auxiliary tooling is an integrated structural component.

[0011] The auxiliary tooling is a two-section structure connected by bolts, and the joint surfaces of the auxiliary tooling are symmetrically arranged along the flange plate.

[0012] The auxiliary tooling is arranged in pairs, and each pair of auxiliary tooling is correspondingly installed on the top and bottom of the steel box girder.

[0013] The method for turning over a large steel box girder provided by the present invention is realized by using auxiliary tooling which has a simple structure, low cost and is easy to use. After being installed on the steel box girder, the contact mode between the steel box girder and the supporting surface can be changed. Therefore, when performing a lifting operation, the previous operation of turning over in the air can be changed to an action of turning over the steel box girder as a whole by rolling on the supporting surface, thereby saving transportation capacity. The turning operation can be realized by using a lifting equipment with a lifting tonnage greater than half of the dead weight of the steel box girder, which greatly reduces the difficulty and cost of manufacturing the steel box girder. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The structure of the auxiliary tooling of the present invention is schematically shown in FIG. Figure 1 .

[0015] Figure 2 yes Figure 1 AA view.

[0016] Figure 3 The structure of the auxiliary tooling of the present invention is schematically shown in FIG. Figure 2 .

[0017] Figure 4 yes Figure 3 BB direction view.

[0018] Figure 5 It is a schematic diagram of the installation structure of the auxiliary tooling of the present invention on the steel box girder.

[0019] Figure 6 yes Figure 5 CC cross-section diagram in .

[0020] Figure 7 It is a schematic diagram of the turning-over process of the steel box girder described in the present invention. DETAILED DESCRIPTION

[0021] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific working process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0022] The turning method of the large steel box girder described in the present invention is realized by auxiliary tooling.

[0023] like Figure 1-7 As shown, the auxiliary tooling is suitable for a steel box girder P in which the web M is symmetrically arranged with respect to the central axis of the flange plate N, and the spacing between the web plates M is smaller than the width of the flange plate N. An installation cavity is arranged on the inner side of the auxiliary tooling, and the installation cavity has a first contact surface 1 connected to the flange plate N, a second contact surface 2 connected to the web plate M, and a clamping groove 3 connecting the first contact surface 1 and the second contact surface 2, and each clamping groove 3 is adapted to the flange plate extension section on the side (i.e., the flange plate N located on the outer side of the web plate M). The outer side of the auxiliary tooling is arranged as an arc surface 4, which is symmetrically arranged along the central axis of the flange plate N, and the ends of the arc surface 4 are arranged on both sides of the web plate M. After the auxiliary tooling is installed on the steel box girder P, the flange plates N at both ends of the steel box girder P are surrounded by the outer arc surface 4. Therefore, the steel box girder P installed with the auxiliary tooling is equivalent to converting the plane structure of the end into an arc surface structure, and when landing, it can roll on the spot with the help of the arc surface. Preferably, straight sections 5 are connected to both ends of the arc surface 4, and the straight sections 5 are arranged parallel to the web M. When the straight sections 5 touch the ground, the steel box girder P can be stopped from rolling, which is beneficial for operations such as adjusting the lifting point of the lifting equipment.

[0024] The auxiliary tooling is welded from steel plates, and reinforcing ribs 6 are welded on both sides of the steel plates to improve the structural strength. Usually, the auxiliary tooling is an integrated structural part. When installing, align the installation cavity with the steel box girder P, and move from the end of the girder body to the center to the desired position; when the web of the steel box girder P adopts a variable cross-section structure, its lower flange plate N usually has an arc, so the auxiliary tooling of the integrated structure cannot be installed through the sleeve. At this time, the auxiliary tooling is made into a two-section structure, that is, the auxiliary tooling is divided into two along the center line of the flange plate N. When in use, the above two parts are buckled to the specified position of the lower flange plate N, and high-strength bolts 7 are installed on the joint surface of the two to connect and fix.

[0025] The turning method of the large steel box girder of the present invention comprises the following steps: The first step is to select a suitable number of auxiliary tooling according to the length of the steel box girder P, and install them at the top and bottom of the steel box girder P according to the lifting plan. For the steel box girder P with a variable cross-section structure, half of the auxiliary tooling of the two-section structure should be selected for installation at the bottom of the steel box girder P. Normally, the auxiliary tooling is arranged in pairs, and each pair of auxiliary tooling is correspondingly installed at the top and bottom of the steel box girder P, wherein the arc surface of the auxiliary tooling is located above the upper flange plate and below the lower flange plate. For the convenience of description, in this embodiment, the auxiliary tooling installed at the upper flange plate N is referred to as the upper tooling Z1, and the auxiliary tooling installed at the lower flange plate N is referred to as the lower tooling Z2.

[0026] The second step is to hoist the steel box girder P by means of lifting equipment, and connect the arc surface of the lower tooling Z2 with the supporting surface.

[0027] The third step is to give the steel box girder P a turning boost through the lifting equipment, so that the steel box girder P rolls 90° along the supporting surface under the action of the arc surface of the lower tooling Z2. At this time, one side of the upper tooling Z1 and the lower tooling Z2 are both connected to the supporting surface, and the web M of the steel box girder P is located above the supporting surface.

[0028] The fourth step is to adjust the lifting point of the lifting equipment on the steel box girder P, and give the steel box girder P a flipping boost through the lifting equipment again, so that the steel box girder P continues to roll 90° along the supporting surface under the action of the arc surface of the upper tooling Z1. At this time, the upper flange plate N is at the bottom (connected to the supporting surface) and the lower flange plate N is at the top, completing the flipping of the steel box girder P.

[0029] It should be noted that, in the description of the present invention, terms indicating orientation or positional relationships, such as "front", "rear", "left", "right", "vertical", "horizontal", "inside", "outside", etc., are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

Claims

1. A method for turning over a large steel box girder, achieved by auxiliary tooling, characterized in that: The auxiliary tooling is provided with an arc surface on the outside, and a mounting cavity is provided on the inside of the auxiliary tooling, wherein the mounting cavity has a first contact surface connected to the flange plate, a second contact surface connected to the web plate, and a slot connecting the first contact surface and the second contact surface, wherein the slot is adapted to the extended section of the flange plate; The turning method comprises: The first step is to select a suitable number of auxiliary toolings according to the length of the steel box girder, and install the auxiliary toolings on the top and bottom of the steel box girder, wherein the arc surface of the auxiliary toolings is located above the upper flange plate and below the lower flange plate; The second step is to hoist the steel box girder by means of lifting equipment, and make the arc surface of the auxiliary tooling at the bottom of the steel box girder connect with the supporting surface; The third step is to use the lifting equipment to give the steel box girder a turning boost, so that the steel box girder rolls 90° along the supporting surface under the action of the bottom auxiliary tooling. At this time, the side of the auxiliary tooling is connected to the supporting surface, and the web of the steel box girder is located above the supporting surface; The fourth step is to adjust the lifting point of the lifting equipment on the steel box girder so that the top auxiliary tooling of the steel box girder continues to roll 90° along the supporting surface. At this time, the upper flange plate is at the bottom and the lower flange plate is at the top, completing the turning over of the steel box girder.

2. The method for turning over a large steel box girder according to claim 1, characterized in that: The web plates of the steel box girder are arranged symmetrically to the central axis of the flange plates, and the web plate spacing is smaller than the width of the flange plates.

3. The turning method of a large steel box girder according to claim 1, characterized in that: The arc surface is symmetrically arranged along the central axis of the flange plate, and the ends of the arc surface are arranged on both sides of the web plate.

4. The turning method of a large steel box girder according to claim 1, characterized in that: The end of the arc surface is connected with a straight section, and the straight section is arranged parallel to the web.

5. The method for turning over a large steel box girder according to claim 1, characterized in that: The auxiliary tooling is formed by welding steel plates, and the steel plates are provided with reinforcing ribs.

6. The turning method of a large steel box girder according to claim 1, characterized in that: The auxiliary tooling is an integrated structural component.

7. The turning method of a large steel box girder according to claim 1, characterized in that: The auxiliary tooling is a two-section structure connected by bolts, and the joint surfaces of the auxiliary tooling are symmetrically arranged along the flange plate.

8. The method for turning over a large steel box girder according to claim 1, characterized in that: The auxiliary tooling is arranged in pairs, and each pair of auxiliary tooling is correspondingly installed on the top and bottom of the steel box girder.

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