CN115958319A - Welding deformation control method for eccentric welding joint - Google Patents

Abstract

The invention discloses a welding deformation control method for an eccentric welding joint, which comprises the following steps: pre-deformation setting is carried out on a panel to be welded before welding, the pre-deformation setting position is a welding deformation generation area, and the pre-deformation setting pre-bending direction is the reverse direction of the welding deformation trend; installing a reinforcing tool on the opposite side of a welding seam of the panel to be welded; welding a welding seam and removing a reinforcing tool; and (4) stress relief after welding. According to the invention, through pre-deformation before welding, constraint of a reinforcing tool and stress relief after welding, the welding deformation can be effectively controlled, and the manufacturing precision of the steel member in the form of an eccentric welding joint is ensured.

Description

Welding deformation control method for eccentric welding joint

Technical Field

The invention relates to steel member manufacturing, in particular to a welding deformation control method for an eccentric welding joint.

Background

In a steel member, the angle joint is generally composed of steel plates with similar restraint degree and plate thickness, the filling amount of a welding seam is moderate, and the welding seam is distributed in the center compared with a web plate and a cover plate. Meanwhile, the welding filling amount is small, the web angular deformation tendency and the cover plate bending deformation tendency in the welding process are small, the web angular deformation tendency and the cover plate bending deformation tendency are restrained by the steel plate, the web angular deformation tendency and the cover plate bending deformation tendency are usually existed in the integral structural member in the internal stress form, and the welding deformation is small.

However, some steel members are specially constructed, so that there is a case that a member with stronger overall rigidity needs to be welded to a single thin plate in a penetration weld form, and the inner side of the member has no welding space and can be welded only on one side on the outer side, for example, a steel anchor beam of a certain steel tower project needs to be welded with an anchor beam block to an anchor beam bottom plate, as shown in fig. 6; still other welded joints are designed to weld a thin plate with a deep groove in an extra-thick plate, for example, in a steel tower project, a groove in an extra-thick bearing plate of 120mm needs to be welded to a thin-wall plate of 40mm, as shown in fig. 2.

In the two cases, the weld is eccentrically distributed compared to the overall or local structure of the structural member, the flatness of the welded back cover plate of such an eccentric fillet joint is severely out of tolerance, and the flatness is difficult to correct by fire at the later stage, which is particularly prominent in long welds.

Disclosure of Invention

The purpose of the invention is as follows: the invention provides a welding deformation control method for an eccentric welding joint aiming at the problems pointed out in the background technology.

The technical scheme is as follows: the invention provides a welding deformation control method for an eccentric welding joint, which comprises the following steps:

pre-deformation setting is carried out on a panel to be welded before welding, the pre-deformation setting position is a welding deformation generation area, and the pre-deformation setting pre-bending direction is the reverse direction of the welding deformation trend;

installing a reinforcing tool on the opposite side of a welding seam of a panel to be welded;

welding a welding seam;

dismantling a reinforcing tool;

and (4) stress relief after welding.

Furthermore, pre-welding pre-deformation setting is carried out in a fire bending mode, and the pre-deformation setting angle is 6-16 degrees.

Further, the reinforcing tool is of a frame structure and is made of batten ribs, and the reinforcing tool is internally provided with separated triangles for stabilizing the structure.

Further, the reinforcing tool is fixed on the panel to be welded in a spot welding mode.

Further, the welding is carried out by adopting multi-layer and multi-pass welding with small line energy.

And further, after welding is finished, a carbon arc gouging is adopted to clean the reinforcing tool for positioning welding and remove the reinforcing tool.

Furthermore, the internal stress is eliminated by adopting a flame heating mode after welding, and the heating temperature is 550-650 ℃.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: through the measures of pre-deformation before welding, reinforcement tool constraint and post-welding stress relief, the welding deformation is effectively controlled, and the manufacturing precision of the steel member in the form of the eccentric welding joint is guaranteed.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention are briefly described below, and it is obvious that the drawings described below are only embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a bearing block;

FIG. 2 is a schematic view of a weld between a pressure bearing plate and a wall plate;

fig. 3 is a schematic view of a pre-deformed panel by fire bending, wherein (a) in fig. 3 is a schematic view of a line of fire positions, and (b) in fig. 3 is a side view of the pre-deformed panel by fire bending;

FIG. 4 is a schematic structural view of a reinforcement tool;

FIG. 5 is a schematic view of a reinforcement fixture installed on the outside of a panel;

fig. 6 is a schematic structural view of the steel anchor beam.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of protection of the present invention.

The invention provides a welding deformation control method for an eccentric welding joint, which is mainly characterized in that a panel is pre-deformed before welding, and reinforcing tools are used for performing forced constraint on the back of the panel to enhance the rigidity of a corner joint panel, so that the welding deformation of a component is reduced, and the acceptance requirement of a steel component is met. The welding deformation control method specifically comprises the following steps:

(1) Pre-weld set pre-deformation

Pre-welding pre-deformation setting is carried out in a fire bending mode, the pre-deformation setting position is a welding deformation generation area, the pre-deformation setting pre-bending direction is the reverse direction of the welding deformation trend of the steel member, and the pre-deformation setting angle is 6-16 degrees.

(2) Manufacturing and reinforcing tool

The maximum hot bending amount of 16 degrees can be realized by the fire-baking process, so that the structural form and the characteristics of the steel member to be manufactured are combined when the reinforcing tool is manufactured. The outline size of the reinforcing tool is designed by fully combining the structural characteristics of the steel member and the welding deformation coverage area. The reinforcing tool is preferably made into a frame structure with a triangular inner part, so that the reinforcing tool can play a role in self-stabilization under the condition of minimum material consumption.

(3) Assembly reinforcing tool

And (4) installing a reinforcing tool to the side with weaker rigidity of the eccentric welding joint so as to achieve the purpose of balancing the rigidity of the welding joint. Particularly, the side with weaker rigidity of the eccentric welding joint is the different side of a panel of a welding seam to be welded, the reinforcing tool is fixed with the panel through spot welding, and the difficulty in dismounting the reinforcing tool after welding is reduced as much as possible on the basis of achieving the purpose of controlling deformation.

(4) Welding of welded seams

And welding is carried out by adopting small-line energy multi-layer and multi-pass welding so as to reduce welding deformation in the welding process.

(5) Reinforcement tool dismantling

And after the welding is finished, cleaning the reinforcing tool by using a carbon arc gouging and welding in a positioning way and removing the reinforcing tool. And after the base material and the reinforcing tool are removed, repair welding and polishing are carried out on the careless damaged part of the base material and the reinforcing tool. The reinforcing tool can be used repeatedly.

(6) Post weld destressing

Because of the forced constraint deformation, the internal stress in the component is large, and the internal stress is eliminated by heating to 550-650 ℃ with flame after welding.

The welding deformation control method for the eccentric welding joint provided by the invention is further described with reference to specific examples.

Example one

As shown in figure 1, the bearing block structure for a large-scale bridge steel tower is characterized in that a groove fillet weld is formed between an ultra-thick bearing plate and a steel tower wall plate, the ultra-thick bearing plate is of an octagonal structure, the plate thickness is 120mm, the maximum outline dimension is 15790mm multiplied by 15790mm, the specification plate thickness of the steel tower wall plate is 40mm, the plate width is 1000mm, and the periphery of the bearing plate and the wall plate are required to be welded according to the fusion depth and not less than 80 mm. As shown in fig. 2, which is a schematic view of a weld joint between the pressure bearing plate and the wall plate, the weld joint is in an eccentric structure, and such a large weld filling amount will inevitably cause an out-of-flatness of the wall plate. In order to ensure the manufacturing precision of the member, the pressure-bearing block is manufactured by adopting the welding deformation control method.

(1) Pre-weld set pre-deformation

After the wall plate and the bearing plate are assembled and positioned, the wall plate and the bearing plate are subjected to fire bending, specifically, a bearing plate assembly position line is marked on the non-welding-seam side of the wall plate, the fire position is the outer side of the wall plate, the fire position is 20mm away from the bearing plate position line, and the fire direction is the welding seam length direction, as shown in (a) in fig. 3. The firing temperature was 700 ℃, the pre-bending direction was outward bending of the panel, and the pre-deformation setting angle was 10 °, as shown in fig. 3 (b).

(2) Manufacturing and reinforcing tool

And (4) combining the distribution of the welding seams and the welding deformation area, and manufacturing a reinforcing tool by using the lath ribs. As shown in FIG. 4, the reinforcing tool is of a frame structure, the length of the reinforcing tool is 3000mm, the width of the reinforcing tool is 400mm, the height of the reinforcing tool is 200mm, and the reinforcing tool is divided into a plurality of triangular areas to play a role in stabilizing the structure. The plate rib material is Q235B, and thickness is 40mm, and the board width is 200mm, and the length is worth according to the drawing size. The plate ribs are connected according to shallow grooves or fillet welds.

(3) Assembly reinforcing tool

As shown in fig. 5, the reinforcing tool is assembled to the outer side of the wall plate to enhance the rigidity of the wall plate, the assembling position of the reinforcing tool is aligned with the center of the welding joint, the reinforcing tool and the wall plate of the steel tower are fixed by spot welding, the spot welding length is 50mm, and the spot welding interval is 100mm.

(4) Welding of welded seams

The groove of the welding joint is designed into a double-sided J-shaped groove to reduce welding filling amount, the lower limit of welding line energy in welding process specifications is adopted during welding, and in the embodiment, the welding line energy is 15KJ/cm to reduce welding deformation.

(5) Reinforcement tool dismantling

And after welding, cleaning the reinforcement tool by a carbon arc gouging and welding in a positioning way and dismantling the reinforcement tool. And after the base material and the reinforcing tool are removed, repair welding and polishing are carried out on the carelessly damaged part of the base material and the reinforcing tool. The reinforcing tool can be used repeatedly.

(6) Post weld destressing

Because of the forced constraint deformation, the internal stress in the component is larger, and the stress is removed by heating to 600 ℃ with flame after welding.

Example two

As shown in FIG. 6, the steel anchor beam structure of a large bridge steel tower is provided, the anchor beam block of the upper anchoring structure is a rigid member and needs to be welded with an anchor beam bottom plate in a single-sided penetration welding line mode, and the flatness required by the anchor beam bottom plate reaches the precision requirement of 1 mm/m. The welding seam with large filling amount will cause the flatness of the anchor beam bottom plate to be out of tolerance. In order to guarantee the manufacturing precision of the components, the steel anchor beam is manufactured by adopting the welding deformation control method. Similar to the embodiment, the manufacturing method is to note that the size of the reinforcing tool needs to be designed additionally according to the actual length and distribution of the welding seam of the component, and the assembling position of the reinforcing tool is the lower side of the anchor beam bottom plate.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any modifications or alternatives that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (7)

1. A welding deformation control method for an eccentric welding joint is characterized by comprising the following steps:

pre-deformation setting is carried out on a panel to be welded before welding, the pre-deformation setting position is a welding deformation generation area, and the pre-deformation setting pre-bending direction is the reverse direction of the welding deformation trend;

installing a reinforcing tool on the opposite side of a welding seam of a panel to be welded;

welding the welding seam;

dismantling a reinforcing tool;

and (4) stress relief after welding.

2. The method of claim 1, wherein the pre-welding pre-deformation setting is performed by a fire bending method, and the pre-deformation setting angle is 6-16 °.

3. A method according to claim 1, characterised in that the reinforcement means is a frame structure made of lath ribs with spaced triangles in the interior for stabilising the structure.

4. The method according to claim 1, characterized in that the reinforcement tool is fixed to the panel to be welded by spot welding.

5. The method of claim 4, wherein the applying is performed using a low line energy multi-layer multi-pass weld.

6. The method according to claim 4 or 5, characterized in that after welding is completed, the reinforcement tool is cleaned by a carbon arc gouging and tack welded and removed.

7. The method as claimed in claim 1, wherein the internal stress is removed by flame heating at 550-650 ℃ after welding.

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