Welding method for box-type steel structural component

Abstract

The invention discloses a box-type steel structural component welding method which comprises the following steps: S1, determining a welding seam form and a welding sequence of a box-type steel structural component according to a structural form of the box-type steel structural component; s2, welding is carried out according to the determined welding sequence, and the inner partition plate of the box-type structure is welded by adopting a fusion nozzle electroslag welding matched compensation heating method; wherein the box-type steel structural member is welded in a back-and-forth reverse face and segmented welding mode, and the transverse partition plates of the box-type steel structural member are welded according to the multi-layer and multi-pass welding sequence. According to the component structure, the reasonable welding seam form and the welding sequence are determined, welding is carried out according to the determined welding sequence, the inner partition plate of the box type structure is welded through nozzle electroslag welding, meanwhile, a compensation heating method is adopted, deformation such as distortion and sidewise bending of the component and residual stress are reduced, the correction time after welding is saved, and the welding seam repair rate is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of welding of steel structure members, and particularly relates to a welding method for box-shaped steel structure members. Background Art

[0002] At present, the steel plates commonly used for box-shaped members often have a large thickness and a high strength grade. When welding, the amount of deposited metal of the filler welding material is large, the welding time is long, and the total heat input is high. Therefore, the post-weld stress and deformation of the structure are large, and the aspect ratio of the cross-section of the member is large, making it difficult for personnel to enter, which affects the manual welding of the internal partition plates. Moreover, layered tearing defects are likely to occur at the "cross-corner joints and T-shaped corner joints" of the box-shaped members in the thickness direction of the steel plates. Summary of the Invention

[0003] The purpose of the present invention is to provide a welding method for box-shaped steel structure members to overcome the defects of the prior art, reduce deformations such as member distortion and side bending, as well as residual stress, save the time for post-weld correction, and reduce the weld repair rate.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A welding method for box-shaped steel structure members includes the following steps:

[0006] Step S1: Determine the weld form and welding sequence of the box-shaped steel structure member according to the structural form of the box-shaped steel structure member;

[0007] Step S2: Weld according to the determined welding sequence, and use consumable guide electro-slag welding combined with the compensation heating method to weld the internal partition plate of the box-shaped structure;

[0008] Among them, the box-shaped steel structure member is welded by the method of back and forth on the reverse side and segmented welding, and the welding sequence of the transverse partition plates of the box-shaped steel structure member is carried out according to the sequence of multi-layer and multi-pass welding.

[0009] In one embodiment, step S1 includes:

[0010] Obtain the structural form of the member. If the structural form of the box-shaped steel structure member is a square shape;

[0011] Then spot weld and assemble to form a box-shaped structure on the U-shaped assembly machine and the box-shaped assembly machine in sequence.

[0012] In one embodiment, step S1 includes:

[0013] Obtain the structural form of the member. If the structural form of the box-shaped steel structure member is a rectangular shape;

[0014] First, assemble it into an H-shaped structure on an H-shaped assembly machine, then perform cross-diaphragm resistance welding, then assemble it into a U-shaped structure on a U-shaped assembly machine, and finally assemble it into a Japanese-character-shaped box-shaped member on the U-shaped assembly machine.

[0015] In one embodiment, step S1 includes:

[0016] Obtain the structural form of the member. If the structural form of the box-shaped steel structure member is a field character shape;

[0017] First, assemble it into an H-shaped structure on an H-shaped assembly machine, install cover plates on both sides of the H-shaped structure, then perform cross-diaphragm resistance welding, then assemble it into a U-shaped structure on a U-shaped assembly machine, and finally assemble it into a field character-shaped box-shaped structure on the U-shaped assembly machine.

[0018] In one embodiment, step S1 further includes:

[0019] If the structural form of the box-shaped steel structure member is a Japanese-character shape, its welding sequence is:

[0020] First, assemble to form an H-shaped structure, weld two passes on the weld below the connection point of one end of the cross plate and the vertical plate, then gouge the root of the weld above the connection point with carbon arc air gouging and weld two passes, and then perform the same welding operation on the weld of the connection point of the other end of the cross plate and the vertical plate;

[0021] After the H-shaped steel beam is welded and corrected, install the top and bottom webs on the H-shaped steel beam with backing plates and weld, weld two passes on the welds at both ends of the bottom web and the vertical plate, and then weld two passes on the welds at both ends of the top web and the vertical plate on the reverse side.

[0022] In one embodiment, step S1 further includes:

[0023] If the structural form of the box-shaped steel structure member is a field character shape, its welding sequence is:

[0024] First, assemble to form an H-shaped structure, weld two passes on the weld below the connection point of one end of the cross plate and the vertical plate, then gouge the root of the weld above the connection point with carbon arc air gouging and weld two passes, and then perform the same welding operation on the weld of the connection point of the other end of the cross plate and the vertical plate;

[0025] After the H-shaped steel is welded and corrected, install the web perpendicular to the cross plate between the vertical plates, first weld two passes on the weld on one side below the cross plate, then weld two passes on the other side, and then weld the welds on one side above the cross plate in the same welding manner;

[0026] After the king character shape is welded and corrected, install the top and bottom webs on the king character-shaped steel beam with backing plates and weld, weld two passes on the welds at both ends of the bottom web and the vertical plate, and then weld two passes on the welds at both ends of the top web and the vertical plate on the reverse side.

[0027] In one embodiment, the diaphragm includes a thick plate and a thin plate;

[0028] When the diaphragm is a thin plate, welding is carried out in sequence according to the multi-layer and multi-pass welding sequence on the front side of the diaphragm;

[0029] When the diaphragm is a thick plate, first weld two layers on the front side of the diaphragm, then gouge the root on the back side and complete the welding on the back side, and then return to the front side until the welding is completed.

[0030] In one embodiment, step S2 further includes:

[0031] For the longitudinal seams of the box-shaped steel structure members, two submerged arc automatic welding machines are used to weld two welds simultaneously, and multiple welds are carried out from one end to the other end of the box-shaped steel structure member at the same time.

[0032] In one embodiment, step S2 further includes:

[0033] During the welding of the longitudinal seams of the box-shaped steel structure member, first weld the welds between the middle web and the flange and assemble and weld the diaphragm, and then weld the four longitudinal seams of the outer web.

[0034] In one embodiment, step S2 further includes:

[0035] On the upper surface longitudinal seam of the box-shaped steel structure member and the lower openings of the two side plates, infrared electric heating preheating plates are pasted at the same time. Multiple electric heating preheating plates are energized for preheating at the same time, and the arc striking plates are installed. Welding is carried out in the same direction simultaneously by two submerged arc welding machines. During the welding process, the temperature of the weld center and both sides of the weld is measured.

[0036] The beneficial effects of the present invention are as follows:

[0037] According to the structure of the member, a reasonable weld form and welding sequence are determined, welding is carried out according to the determined welding sequence, the inner diaphragm of the box-shaped structure is welded by using consumable nozzle electro-slag welding, and at the same time, the compensation heating method is adopted to reduce the deformation such as member distortion and side bending and the residual stress, save the time for post-weld correction, and reduce the weld repair rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In the following, the present invention will be described in more detail based on embodiments and with reference to the drawings. Among them:

[0039] Figure 1 Shows the erection schematic diagram of the mouth-shaped box-shaped member of the present invention;

[0040] Figure 2 Shows the erection schematic diagram of the day-shaped box-shaped member of the present invention;

[0041] Figure 3 Shows the erection schematic diagram of the field-shaped box-shaped member of the present invention;

[0042] Figure 4 Shows the schematic diagram of the assembly sequence of the "Ri"-shaped box girder of the present invention;

[0043] Figure 5 Shows the schematic diagram of the assembly sequence of the "Tian"-shaped box girder of the present invention;

[0044] Figure 6 Shows the schematic diagram of the welding sequence of the "Tian"-shaped box girder of the present invention;

[0045] Figure 7 Shows the schematic diagram of the welding sequence of the "Kou"-shaped box member of the present invention;

[0046] Figure 8 Shows the schematic diagram of the welding sequence of the "Ri"-shaped box member of the present invention;

[0047] Figure 9 Shows the schematic diagram of the welding sequence of the "Tian"-shaped box member of the present invention;

[0048] Figure 10 Shows the schematic diagram of the welding direction of the diaphragm of the present invention;

[0049] Figure 11 Shows the schematic diagram of the welding sequence of the diaphragm of the present invention;

[0050] Figure 12 Shows the schematic diagram of the welding sequence of the same weld of the diaphragm of the present invention;

[0051] Figure 13 Shows the schematic diagram of the welding direction of the longitudinal seam of the box member of the present invention;

[0052] Figure 14 Shows the schematic diagram of the welding sequence of the longitudinal seam of the box member of the present invention;

[0053] Figure 15 Shows the schematic diagram of the relationship between shutdown and side bend of the present invention;

[0054] Figure 16 Shows the schematic diagram for ensuring that the completion tolerance of the box member of the present invention meets the requirements;

[0055] Figure 17 Shows the schematic diagram of the welding sequence of the longitudinal seam of the "Kou"-shaped box member of the present invention;

[0056] Figure 18 Shows the schematic diagram of the welding sequence of the longitudinal seam of the "Ri"-shaped box member of the present invention;

[0057] Figure 19 Shows the schematic diagram of the welding sequence of the longitudinal seam of the "Tian"-shaped box member of the present invention;

[0058] In the drawings, like parts are designated by like reference numerals. The drawings are not drawn to scale. Detailed Description of the Invention

[0059] The present invention will be further described below in conjunction with the drawings.

[0060] The present invention provides a welding method for box-shaped steel structure members, including:

[0061] Step S1: Determine the weld form and welding sequence of the box-shaped steel structure member according to the structural form of the box-shaped steel structure member;

[0062] Step S2: Weld according to the determined welding sequence, and use consumable nozzle electro-slag welding combined with compensation heating method to weld the inner partition of the box-shaped structure;

[0063] Among them, the box-shaped steel structure member is welded by the method of back and forth reverse and segmented welding, and the welding sequence of the transverse diaphragms of the box-shaped steel structure member is carried out according to the sequence of multi-layer and multi-pass welding;

[0064] Specifically, in step S1, the following several structural forms are included:

[0065] For the square-shaped box-shaped member, as Figure 1 shown, first assemble it into a U-shaped structure on a U-shaped assembling machine, and then assemble it into a box-shaped structure on a box-shaped assembling machine;

[0066] For the rectangular-shaped box-shaped member, as Figure 2 shown, first assemble it into an H-shaped structure on an H-shaped assembling machine, then carry out transverse diaphragm tack welding, then assemble it into a U-shaped structure on a U-shaped assembling machine, and finally assemble it into a rectangular-shaped box-shaped member on a U-shaped assembling machine;

[0067] For the cross-shaped box-shaped member, as Figure 3 shown, first assemble it into an H-shaped structure on an H-shaped assembling machine, install cover plates on both sides of the H-shaped structure, then carry out transverse diaphragm tack welding, then assemble it into a U-shaped structure on a U-shaped assembling machine, and finally assemble it into a cross-shaped box-shaped structure on a U-shaped assembling machine;

[0068] Specifically, during the assembling process of the rectangular-shaped box-shaped member, as Figure 4 shown;

[0069] First, Figure 4 assemble the No. 1 cover plate and the No. 2 web in

[0070] to form an H-shaped steel, level it with a level. The cover plate and web must be leveled before installation. After installation, reinforce the welding of the lifting arm. After welding, use a 60-type straightening machine for straightening, and then use flame straightening for the cover plate and web angle. The flame temperature should not exceed 900 °C, and avoid watering during cooling;After the angle gauge is calibrated, install the left and right inner partitions and weld three sides, and use electroslag welding for the other side. Finally, install two No. 3 plates on the welded H-shaped steel on the fixture, and then perform welding, flame straightening, general assembly, re-welding, grinding, and flame straightening. The No. 1 plate is the cover plate without groove, the No. 2 plate is the web plate with K-shaped groove, the No. 3 plate is the reinforced web plate with single-sided groove and backing plate welding, and all the welds between the cover plate and the web plate are full penetration welds;

[0071] Furthermore, as Figure 5 shown, during the assembly process of the cross-shaped box girder;

[0072] First, assemble the No. 1 cover plate and the No. 2 web plate in Figure 5 into an H-shaped steel, and use a 60-type flange straightening machine to straighten the flange after welding. Then, install the No. 3 reinforced cover plate on both sides of the H-shaped steel, and then install the upper, lower, left, and right inner partitions and perform hanging welding and flame straightening;

[0073] After welding and flame straightening, finally install four No. 4 web plates and perform welding, flame straightening, general assembly, re-welding, grinding, and flame straightening. The No. 1 cover plate has no groove, the No. 2 and No. 3 plates have K-shaped grooves, and the No. 4 web plate has a single-sided groove with backing plate welding;

[0074] It should be noted that for the K-shaped grooves of the day-shaped box girder and the cross-shaped box girder, all are single-sided welding, and the back side is gouged with carbon arc air gouging and then welded to achieve a full penetration weld of the second level, and a symmetric staggered welding sequence is adopted during welding;

[0075] Specifically, the welding sequence of the cross-shaped box girder is as Figure 6 shown, Figure 6 in which the welds from weld 5 to weld 14 are the weld numbers. The groove of the No. 2 web plate is a K-shaped groove with a 45-degree angle and a 2-mm root face. The groove of the No. 4 web plate is a single-sided groove with a 45-degree angle and a 2-mm root face, and is welded with a 6*30 continuous backing plate. The No. 1 and No. 2 are assembled into an H-shaped steel and a T-shaped steel. For the H-shaped steel, first weld two passes of weld 5, then gouge the root of weld 6 with carbon arc air gouging and weld two passes. Weld weld 9 and weld 10 in the same way as weld 5 and weld 6. Finally, the capping sequence is weld 5, weld 6, weld 9, weld 10;

[0076] After the H-shaped steel is welded and straightened, install the No. 3 plate and first weld two passes of weld 8, then weld two passes of weld 11. Weld weld 7 and weld 12 in the same way as weld 8 and weld 11. Finally, the capping sequence is weld 8, weld 11, weld 7, and weld 12;

[0077] After the king-shaped welding and straightening are completed, install the No. 4 web plate on the king-shaped steel beam with a backing plate and weld. First, weld two passes of weld 13, and weld two passes of weld 14 on the back side. Adopt back-and-forth reverse and segmented welding, and finally complete the welding of the component;

[0078] Among them, during assembly, arc striking plates with a size of 80×100mm and the same thickness should be added at both ends of all welds;

[0079] Furthermore, in the specific welding construction process, determine the welding construction sequence according to the erection sequence of box-shaped steel structures with different structural forms.

[0080] For the mouth-shaped members, as Figure 7 shown, where "1, 2, 3" represent the total welding sequence determined by the erection sequence of each part. "1" represents the weld seam welded by manual arc welding or CO 2 gas shielded welding. "2" represents the weld seam welded by electroslag welding, that is, the weld seam between the diaphragm and the web that cannot be welded by manual arc welding or CO 2 gas shielded welding. "3" represents the weld seam welded by submerged arc automatic welding;

[0081] For the day-shaped members and the field-shaped members, as Figure 8 and Figure 9 shown, where "1, 2, 3, 4" represent the total welding sequence determined by the erection sequence of each part. "1" represents the weld seam welded by submerged arc automatic welding. "2" represents the weld seam welded by manual arc welding or CO 2 gas shielded welding. "3" represents the weld seam welded by electroslag welding, that is, the weld seam between the diaphragm and the web that cannot be welded by manual arc welding or CO 2 gas shielded welding. "4" represents the weld seam welded by submerged arc automatic welding;

[0082] Among them, the welding direction of the diaphragm is as Figure 10 shown:

[0083] The welding direction of the diaphragm of the mouth-shaped member is as Figure 10 (a) shown. The welding direction of the diaphragm of the day-shaped member is as Figure 10 (b) shown. The welding direction of the diaphragm of the field-shaped member is as Figure 10 (c) shown;

[0084] Furthermore, the welding sequence of the diaphragm is as Figure 11 shown:

[0085] The welding sequence of the diaphragm of the mouth-shaped member is as Figure 11 (a) shown. The welding sequence of the diaphragm of the day-shaped member is as Figure 11 (b) shown. The welding sequence of the diaphragm of the field-shaped member is as Figure 11 (c) shown;

[0086] Among them, in the welding sequence of the diaphragm of the field-shaped member, two welders weld simultaneously. In the welding sequence of the diaphragm, "5", "7", and "8" are all electroslag welding;

[0087] In one embodiment, the welding sequence of the same weld seam of the diaphragm is asFigure 12 As shown, both the thin plate and the thick plate are welded according to the principle of multi-layer and multi-pass welding. The welding sequence of the thin plate is as Figure 12 (b) shows, while when welding the thick plate, as Figure 12 (a) shows, first weld the 1st and 2nd layers on the front side, then gouge the root on the back side and weld the 3rd to 6th layers (the back side is fully welded), until the 7th to 14th layers on the front side are welded. And before welding, the welding position should be preheated according to the requirements of preheating;

[0088] In one embodiment, the welding direction of the longitudinal seam of the box-shaped member is as Figure 13 shown,

[0089] It should be noted that for the longitudinal seam, two submerged arc automatic welding machines are used to weld the two weld seams simultaneously and according to the same specification. For the welding of the four longitudinal weld seams, welding is carried out from one end of the box-shaped member to the other end;

[0090] Furthermore, the welding sequence of the longitudinal seam of the box-shaped member is as Figure 14 shown,

[0091] Specifically, the welding sequence of the longitudinal seam of the mouth-shaped box-shaped member is as Figure 14 (a) and Figure 17 shown;

[0092] The welding sequence of the longitudinal seam of the day-shaped box-shaped member is as Figure 14 (b) and Figure 18 shown;

[0093] The welding sequence of the longitudinal seam of the field-shaped box-shaped member is as Figure 14 (c) and Figure 19 shown;

[0094] It should be noted that taking the welding sequence of the longitudinal seam of the day-shaped box-shaped member as an example, after welding the weld seam between the middle web and the flange and assembling and welding the transverse diaphragm, then weld the four longitudinal seams of the outer web. The welding requirements for the longitudinal seam of the field-shaped box-shaped member are the same as those of the day-shaped box-shaped member;

[0095] Specifically, taking the welding sequence of the longitudinal seam of the day-shaped box-shaped member as an example, first use submerged arc automatic welding to weld 2 to 3 layers of the two weld seams ①① of the middle web, then turn it over and weld 4 to 6 layers of the two weld seams ②② on the other side of the web, then turn it over and weld in sequence until the weld seams on both sides of the middle web are fully welded. Secondly, use manual arc welding or CO 2 welding to weld the transverse diaphragm with the middle web and the wing plate, then use submerged arc automatic welding to weld 2 to 3 layers of the two weld seams ③③ of the outer web, then turn it over and weld 4 to 6 layers of the two weld seams ④④ on the other side of the outer web, then turn it over and weld in sequence until the weld seams of the outer web are fully welded;

[0096] In one embodiment, infrared electric heating preheating plates are simultaneously and properly attached to the longitudinal seam on the upper surface of the box-shaped member and the lower openings of the two side plates. The four preheating plates are simultaneously powered on for preheating. The preheating personnel frequently measure the temperature. The temperature measurement points are evenly distributed at 100 mm on each side of the weldable weld and at the weld center. The arc striking plates are properly installed, and two submerged arc automatic welding machines are used to weld in the same direction simultaneously. When 2 to 3 welds are welded well, in order to prevent the intermittent weld on the reverse side of the box-shaped member from cracking due to excessive welding stress, the member should be turned over. If the intermittent weld on the reverse side cracks, the automatic welding must be immediately stopped and measures should be taken in a timely manner. When necessary, the preheating plates are removed, the member is lifted out of the automatic welding fixture, turned over, and the residual weld of the intermittent weld between the cracks is removed by carbon gouging and then reassembled for intermittent welding. If the crack is relatively large, it can be repaired directly without lifting out of the fixture, but the residual weld at the cracked part must be planed clean;

[0097] If the box-shaped member is bent sideways, when it is about 10 mm (in the hot state), one welding machine should be stopped, and the other one continues to weld to correct the sideways bend. When the sideways bend is within 10 mm, the welding machine is restarted. The relationship between stopping and sideways bend is as Figure 15 shown;

[0098] If the box-shaped member deflects downward (in the welding hot state) and the visual inspection plate is 10 mm, the heating temperature of the preheating plate at the lower part of the box-shaped member should be increased. If it arches upward and is about 10 mm visually, the heating temperature of the preheating plate at the lower part of the box-shaped member should be decreased, as Figure 16 shown;

[0099] Among them, during the entire welding process of the whole box-shaped member, by continuously adjusting the welding heat and the heat of the preheating plates, the vertical deflection and sideways bend of the box-shaped member are always controlled within about 10 mm to ensure that the completion tolerance of the box-shaped member meets the requirements;

[0100] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0101] Although the present invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments, and that other arrangements may be designed, without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the different dependent claims and the features described herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in connection with a separate embodiment may be used in other described embodiments.

Claims

1. A box-type steel structure member welding method, characterized in that: The steps include: Step S1, determining the weld form and welding sequence of the box-type steel structure component according to the structural form of the box-type steel structure component; Step S2, welding is performed according to the determined welding sequence, and the inner partition of the box-type structure is welded by using a nozzle electroslag welding combined with a compensating heating method; Among them, the box-type steel structure components are welded by back and forth reverse and segmented welding methods, and the welding sequence of the cross partitions of the box-type steel structure components is carried out in the order of multi-layer and multi-pass welding.

2. A box-type steel structure member welding method according to claim 1, characterized in that: Step S1 includes: Get the structural form of the component. If the structural form of the box-type steel structure component is a square shape; The box-type structure is formed by spot welding on the U-type assembly machine and the box-type assembly machine in sequence.

3. A box-type steel structure member welding method according to claim 1, characterized in that: Step S1 includes: Get the structural form of the component. If the structural form of the box-type steel structure component is a Japanese-shaped one; First, assemble it into an H-shaped structure on an H-shaped assembly machine, then perform cross-plate resistance welding, then assemble it into a U-shaped structure on a U-shaped assembly machine, and finally assemble it into a Japanese-shaped box-shaped component on a U-shaped assembly machine.

4. A box-type steel structure member welding method according to claim 1, characterized in that: Step S1 includes: Get the structural form of the component. If the structural form of the box-type steel structure component is a field shape; First, assemble it into an H-shaped structure on an H-shaped assembly machine, install cover plates on both sides of the H-shaped structure, then perform cross-plate resistance welding, then assemble it into a U-shaped structure on a U-shaped assembly machine, and finally assemble it into a field-shaped box structure on the U-shaped assembly machine.

5. A box-type steel structure member welding method according to claim 3, characterized in that: Step S1 also includes: If the structural form of the box-type steel structure member is a Japanese-shaped one, the welding sequence is as follows: First, assemble to form an H-shaped structure, weld two passes of the weld below the connection point between one end of the horizontal plate and the vertical plate, then use carbon arc air planer to clean the root of the weld above the connection point and weld two passes, and then perform the same welding operation on the weld at the connection point between the other end of the horizontal plate and the vertical plate; After the H-shaped steel beam is welded and corrected, the top and bottom webs are installed on the H-shaped steel beam and welded with pads. Two welds are made between the two ends of the bottom web and the vertical plate, and then two welds are made between the two ends of the top web and the vertical plate on the reverse side.

6. A box-type steel structure member welding method according to claim 4, characterized in that: Step S1 also includes: If the structural form of the box-type steel structure member is a field shape, the welding sequence is: First, assemble to form an H-shaped structure, weld two passes of the weld below the connection point between one end of the horizontal plate and the vertical plate, then use carbon arc air planer to clean the root of the weld above the connection point and weld two passes, and then perform the same welding operation on the weld at the connection point between the other end of the horizontal plate and the vertical plate; After the H-beam is welded and calibrated, install the web between the vertical plates and perpendicular to the horizontal plate. First, weld two welds on the side below the horizontal plate, then weld two welds on the other side, and then weld the weld on the side above the horizontal plate in the same way. After the W-shaped welding and correction are completed, the top and bottom webs are installed on the W-shaped steel beam and welded with pads. Two welds are made between the two ends of the bottom web and the vertical plate, and then two welds are made between the two ends of the top web and the vertical plate on the reverse side.

7. A box-type steel structure member welding method according to claim 1, characterized in that: Diaphragms include thick plates and thin plates; When the diaphragm is a thin plate, welding is performed sequentially on the front side of the diaphragm in the order of multi-layer and multi-pass welding; When the diaphragm is a thick plate, first weld two layers on the front side of the diaphragm, then clean the root on the back side and weld the back side, then return to the front side until welding is completed.

8. A box-type steel structure member welding method according to claim 1, characterized in that: Step S2 also includes: The longitudinal seams of the box-type steel structure components are welded simultaneously by two submerged arc automatic welding machines, and multiple welds are welded simultaneously from one end to the other end of the box-type steel structure component.

9. A box-type steel structure member welding method according to claim 8, characterized in that: Step S2 also includes: During the longitudinal seam welding process of box-type steel structure components, the welds between the middle web and the flange are welded first and the cross partitions are welded together, and then the four longitudinal seams of the outer web are welded.

10. A box-type steel structure member welding method according to claim 8, characterized in that: Step S2 also includes: Infrared electric heating preheating plates are affixed to the longitudinal seams on the upper surface of the box-type steel structure components and the lower edges of the two side plates. Multiple electric heating preheating plates are powered on for preheating at the same time, and arc starting plates are installed. Two submerged arc automatic welding machines are used to perform welding in the same direction at the same time. During the welding process, the temperature of the weld center and both sides of the weld is measured.

Images