Local annealing and residue eliminating equipment for welding seam of orthotropic steel bridge deck and using method of local annealing and residue eliminating equipment

Abstract

The invention relates to local annealing and residue eliminating equipment for a welding seam of an orthotropic steel bridge deck and a using method of the local annealing and residue eliminating equipment. The welding seam local annealing and residue eliminating equipment comprises a heating temperature control system, a first mounting seat and a second mounting seat, wherein the first mounting seat is used for being attached to the bottom of a top plate of the orthotropic steel bridge, and the second mounting seat is used for being propped against a longitudinal rib of the orthotropic steel bridge; the second mounting seat is mounted on the first mounting seat; the first mounting seat and the second mounting seat are connected with a first driving piece for driving the first mounting seat and the second mounting seat to move towards the orthotropic steel bridge rib plate; heating plates are fixedly arranged on the side surfaces, deviating from each other, of the first mounting seat and the second mounting seat; and the heating temperature control system is electrically connected with the heating plate. The invention further discloses a using method of the equipment. According to the equipment and the using method thereof, the heating temperature is uniform, the effect is good, use is convenient, adjustability and universality are high, the residual stress of a welding seam is reduced by 75%-80%, and the world problem that an in-service bridge is repeatedly cracked in a short time after being repaired is solved.

Description

Technical Field

[0001] The present application relates to the technical field of bridge maintenance equipment, and in particular to a device for local annealing and removing residual welds of orthotropic steel bridge decks and a method for using the device. Background Art

[0002] Orthotropic steel bridge deck is a structure that bears loads together with the bridge deck top plate, which is composed of vertical and horizontal perpendicular stiffening ribs (longitudinal ribs and transverse ribs). Orthotropic steel bridge deck is one of the important features of modern steel bridges. Orthotropic steel bridge deck structure has the advantages of light weight, high rigidity, high bearing capacity, and easy factory manufacturing. It is widely used in various large and medium span bridges.

[0003] The thickness of the top plate of the orthotropic steel bridge deck is generally 14-18mm, and the longitudinal ribs are usually U-shaped ribs or bulbous flat steel ribs or plate ribs, and the thickness of the longitudinal ribs is generally 6mm or 8mm; during manufacturing, the entire bridge is divided into several sections and assembled in the factory, and the top plate of the bridge deck is welded and fixed with the longitudinal ribs and transverse ribs. After hoisting, the connection between the sections is carried out on the bridge. Usually all longitudinal fillet welds (longitudinal ribs and longitudinal diaphragms, etc.) are through, and the intersection of the transverse ribs or transverse diaphragms with the longitudinal welds and the lower flange of the longitudinal ribs is cut into an arc-shaped notch to avoid them.

[0004] Since welding is a thermal cycle process of rapid local heating and cooling of steel, the parent metal and deposited metal on both sides of the weld will undergo changes in structure and performance during welding. The weld is constrained by the structure and cannot expand and contract freely. After cooling, a large residual stress is generated at the welding site, accompanied by hydrogen embrittlement, embrittlement, hardening or softening, which reduces the performance and strength of the structure. Welding residual stress is the initial stress that has already existed on the cross section of the structure before the structure bears the load. During the service of the structure, the working stress caused by other loads will be superimposed on each other, which will not only reduce the stiffness and stability of the structure, but also seriously affect the fatigue strength of the structure, and the ability to resist stress corrosion cracking and high-temperature creep cracking. The residual stress generated during the welding process will seriously reduce the bearing capacity and fatigue strength of the structure, and even induce cracks and cause catastrophic accidents. As the bridge deck system, the steel bridge deck directly bears the pressure, impact, vibration and shear of vehicle loads, and the bridge deck structure is subjected to complex forces. As the service time of steel bridge deck increases, fatigue cracking is common, especially in the welds between top plate and longitudinal ribs, welds between diaphragms and longitudinal ribs, and the openings of diaphragms. It seriously threatens the safety of bridge structures. Studies have shown that the fatigue life under the coupling of welding residual stress and vehicle load stress decreases by 30% to 40%, and the reduction in fatigue life increases with the increase of residual stress. The residual stress generated by welding is an important factor in inducing and accelerating fatigue cracking of welded joints.

[0005] Post-weld annealing has a good effect on eliminating welding residual stress and hydrogen embrittlement. Post-weld annealing can reduce welding residual stress and improve weld metallographic structure, thereby improving the mechanical properties, corrosion resistance and fatigue resistance of the weld. During the annealing process, with the disappearance of martensite structure, the precipitation of carbon, carbide and hydrogen, dislocation migration, a small amount of plastic deformation and uniform distribution of grains, the internal structure of the material changes, causing the deformation of internal stress to disappear, and the residual stress of the weld joint is reduced and released and presents a uniform distribution. Since the generation of welding residual stress is often accompanied by changes in material properties caused by welding thermal cycles, heat treatment can restore or partially restore the material properties while eliminating residual stress.

[0006] For a long time, there has been insufficient research and attention paid to the post-weld annealing heat treatment of residual stress at home and abroad, especially the lack of relevant equipment for residual stress of orthotropic steel bridge deck welds and post-weld heat treatment. As a result, in-service orthotropic steel bridge decks only use simple repair welding after weld cracking occurs, but do not take necessary post-weld residual stress detection and dehydrogenation measures. As a result, cracks quickly occur at the repair position after repair welding, which directly causes the deterioration of structural strength and reduces the service life of the bridge. It has become a world headache for bridge repair projects at home and abroad.

[0007] In the related art, an oxyacetylene flame generated by a flame gun is used to heat the welding deformation area of ​​the orthotropic steel bridge deck in a targeted manner to eliminate the residual welding deformation. The heat treatment equipment is relatively simple, the heating temperature is difficult to control, and the heating temperature of the local area is not uniform enough. The heating temperature is difficult to control, and the annealing and residual elimination heat treatment effect is not good; especially for the orthotropic steel bridge deck in service, it is difficult to achieve the purpose of annealing and residual elimination. Summary of the invention

[0008] In order to improve the effect and reliability of local annealing and residual removal of welds of in-service orthotropic steel bridge decks, the present application provides a local annealing and residual removal device for welds of orthotropic steel bridge decks and a method for using the same.

[0009] In the first aspect, the present application provides a local annealing and residual removal device for welds of orthotropic steel bridge decks, which adopts the following technical solution: A device for local annealing and removing residual seams of orthotropic steel bridge decks, comprising a first mounting seat for abutting against the bottom of the orthotropic steel bridge top plate and a second mounting seat for abutting against the longitudinal ribs of the orthotropic steel bridge; one end of the second mounting seat is mounted and connected to the first mounting seat; The first mounting seat and the second mounting seat are connected with a first driving member for driving the two to move toward the longitudinal rib direction of the orthotropic steel bridge; A heating plate is fixedly disposed on the side surfaces of the first mounting seat and the second mounting seat which are away from each other; The weld local annealing and residual removal equipment also includes a heating temperature control system, which is electrically connected to the heating plate and is used to control the heating temperature and time of the heating plate.

[0010] The equipment in this application is used to repair fatigue cracking of the longitudinal rib and top plate welds, which are the most common defects in orthotropic steel bridge decks in service. When in use, the equipment is installed at the bottom of the top plate, and the first driving member pushes the first mounting seat and the second mounting seat to move toward the orthotropic steel bridge rib plate and hold it; the heating plate on the first mounting seat abuts against the bottom of the orthotropic steel bridge top plate, and the heating plate on the first mounting seat abuts against the orthotropic steel bridge rib plate; the heating temperature and heating time of the heating plate are controlled by the heating temperature control system, so as to heat treat the weld to eliminate the residual stress of welding, and improve the metallographic structure of the weld, thereby improving the mechanical properties, corrosion resistance and fatigue resistance of the weld.

[0011] By adopting the above technical solution, the heating plate can heat the local area stably and reliably with good controllability and uniform heating temperature, which greatly improves the effect of heat treatment. In addition, the whole equipment is easy to use, stable and reliable.

[0012] The heating temperature control system in this application includes a controller, which can automatically and accurately control the heating time and heating temperature through a pre-set software control program, with a high degree of automation and high work efficiency. It can also be remotely controlled, saving manpower and being safer; at the same time, according to the characteristics of different steel materials, the corresponding selection of the software program can easily realize the application of various materials, meeting the needs of multi-function and diversification.

[0013] Optionally, the first mounting seat and the second mounting seat are both in the form of plates, and one end of the second mounting seat is rotatably connected to one end of the first mounting seat via a rotating shaft; there are at least two first driving members installed on the first mounting seat and the second mounting seat, and the first driving member is a hydraulic rod or an electric push rod; an ear plate corresponding to the first driving member is fixed on the side surface close to the first mounting seat and the second mounting seat, and one end of the first driving member is pinned to the corresponding ear plate, and the other end of the first driving member is provided with a magnetic attraction structure.

[0014] By adopting the above technical solution, multiple first driving members can stably and reliably push the first mounting seat and the second mounting seat to move, and at the same time, the magnetic attraction structure at the end of the first driving member is used to assist in clamping the first mounting seat and the second mounting seat between two adjacent longitudinal ribs, thereby ensuring the stable and reliable installation of the first mounting seat and the second mounting seat, and also enabling the heating plate to fit more closely with the orthogonal anisotropic steel bridge top plate and the longitudinal ribs, thereby improving the heat conduction efficiency, reducing heat loss, and ensuring the heat treatment effect.

[0015] Optionally, a second driving member for pushing the second mounting seat to swing on the first mounting seat is provided between the first mounting seat and the second mounting seat.

[0016] By adopting the above technical solution, the second driving member drives the second mounting seat to swing to adapt to longitudinal ribs of different shapes and ensure that the heating plate on the second mounting seat is more closely fitted to the side of the longitudinal ribs, thereby ensuring the stability and reliability of local heating and improving the annealing and residual removal effect.

[0017] Optionally, the swing amplitude of the second mounting base is in the angle range of 90° to 105° between the second mounting base and the first mounting base.

[0018] By adopting the above technical solution, the heating plate on the second mounting seat swings with the second mounting seat to meet the different welding angle change requirements for connecting different stiffening ribs such as U ribs, I ribs, L ribs, etc., with high overall versatility and easy adjustment.

[0019] Optionally, the second driving member is also a hydraulic rod or an electric push rod; both ends of the second driving member are respectively connected to the side surfaces of the first mounting seat and the second mounting seat that are close to each other.

[0020] By adopting the above technical solution, the second driving member can automatically adjust the swing angle of the second mounting seat according to pre-set programs and parameters, and lock itself after being adjusted into place, thereby meeting the requirements of different longitudinal rib shapes and ensuring its stability and reliability in use.

[0021] Optionally, a first auxiliary mounting seat is fixedly provided at the end of the first mounting seat for abutting against the orthogonal anisotropic steel bridge cross-plate, and a second auxiliary mounting seat is fixedly provided at the end of the second mounting seat for abutting against the orthogonal anisotropic steel bridge cross-plate; the heating plate is also fixedly provided on the sides of the first auxiliary mounting seat and the second auxiliary mounting seat facing away from the first mounting seat and the second mounting seat.

[0022] By adopting the above technical solution, the heating plates on the first auxiliary mounting seat and the second auxiliary mounting seat are abutted against the orthogonal anisotropic steel bridge diaphragm to heat the relevant defective areas, thereby meeting the diversified needs of the equipment of the present application, making it more widely used, and being able to perform heat treatment on multiple locations at the same time, with higher work efficiency.

[0023] Optionally, the first auxiliary mounting seat and the second auxiliary mounting seat are both triangular plates, and the first auxiliary mounting seat and the second auxiliary mounting seat are both perpendicular to the first mounting seat and the second mounting seat; when the first mounting seat is perpendicular to the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat are relatively connected to form a rectangular plate structure; an insulation board is also installed on one side of the first auxiliary mounting seat or the second auxiliary mounting seat; when the angle between the first mounting seat and the second mounting seat is an obtuse angle, the insulation board can block the gap between the first auxiliary mounting seat and the second auxiliary mounting seat.

[0024] By adopting the above technical solution, the use effect of the first auxiliary mounting seat and the second auxiliary mounting seat is guaranteed, while the interference between the two is minimized. The heat preservation plate is used to improve the heat preservation effect when heating the diaphragm.

[0025] Optionally, the heating plate is made of a ceramic electronic heating plate; the first mounting seat, the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat all include a protective shell and a steel frame, the protective shell is a sandwich structure and is filled with thermal insulation cotton, the steel frame is located in the protective shell, the heating plate is connected to the steel frame through a fastener and an insulating asbestos board is fixed between the heating plate and the protective shell.

[0026] By adopting the above technical solution, the heating stability and reliability of the heating plate can be effectively improved, heat loss can be reduced, and the annealing and residual elimination effect can be ensured.

[0027] Optionally, the weld local annealing and residual removal equipment also includes a mobile power station, which is used to supply energy and heat the heating plate and is electrically connected to the heating temperature control system.

[0028] By adopting the above technical solution, the mobile power station supplies energy to the heating plate without the need to set up additional wires, meeting the requirements for use in outdoor environments without electricity and reducing the limitations of the entire equipment.

[0029] In a second aspect, the present application further discloses a method for using a device for local annealing and residual removal of welds of an orthotropic steel bridge deck, wherein the device for local annealing and residual removal of welds of an orthotropic steel bridge deck is used to perform local annealing and residual removal of welds of an orthotropic steel bridge deck; the method for using the device for local annealing and residual removal of welds of an orthotropic steel bridge deck comprises the following steps: S1: Smooth surface: Mill or grind the defective welds of the top plate, diaphragm and rib plate of the orthotropic steel bridge to make the surface smooth; S2: Install and adjust the equipment: install the weld local annealing and residual removal equipment on the bottom of the top plate, the first driving member pushes the first mounting seat and the second mounting seat to move toward the orthotropic steel bridge rib plate and hold it; the heating plate on the first mounting seat abuts against the bottom of the orthotropic steel bridge top plate, and the heating plate on the first mounting seat abuts against the orthotropic steel bridge rib plate; S3: Heat treatment: Select appropriate temperature control program and parameters, preset heating temperature and time, and perform heating annealing, residual dehydrogenation treatment on the weld; S4: Inspection: After the heat treatment is completed, the equipment is dismantled and then residual stress detection and acceptance are carried out.

[0030] The present application is used to carry out local annealing heat treatment on the welding seams of orthogonal anisotropic steel bridge decks. Through the heating plate in the relevant equipment, the outer side of the heating plate is completely fitted to the outer side of the rib plate and the welding corners on the left and right sides of the upper side with the most flat and uniform force. Compared with the existing technology, this achieves uniform annealing heat treatment of the rib plate butt welds, thereby more uniformly eliminating welding residual stress; the relevant equipment in the present application is easy to install and disassemble, has a high degree of automation, and has good heating and heat preservation effects; the entire equipment is easy to carry and can be reused, reducing production costs; the method in the present application is conducive to completing the post-weld annealing of orthogonal anisotropic steel bridge decks, can shorten the construction period, save construction costs, effectively connect the construction processes, conform to the concept of green construction, and has strong practicality. The key technology of the annealing process has the advantages of high stress elimination rate and simple operation.

[0031] In summary, the present application includes at least one of the following beneficial technical effects: 1. In this application, the outer side of the heating plate is completely attached to the outer side of the rib plate and the welding corners on the left and right sides of the upper side with the most flat and uniform force, which can evenly anneal the rib plate butt weld, thereby more evenly eliminating the welding residual stress.

[0032] 2. In this application, the structures of the first mounting seat, the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat are optimized and designed. The insulation structure design can insulate the heating during the temperature increase. During the heat treatment process, the heat loss is delayed, the uneven temperature gradient is reduced, and the predetermined annealing process is ensured to be carried out accurately, which saves costs and improves the heat treatment effect.

[0033] 3. The heating plate in this application adopts a ceramic electronic heating plate, which heats evenly, stably and reliably.

[0034] 4. The relevant equipment in this application is easy to install and disassemble, and realizes local annealing treatment on site of the bridge in service, with good heating and heat preservation effects; the entire equipment is easy to carry and can be reused, which reduces production costs; the construction period in its process method is short, saving construction costs; in particular, local annealing heat treatment is performed on the welds of the orthotropic steel bridge deck in service, the residual stress of the welds is reduced by 75%-80%, the hydrogen embrittlement phenomenon is basically eliminated, the residual elimination effect is obvious, the fatigue performance of the welded joint is improved, and the world's difficult problem of repeated cracking of the bridge in service after short-term repair is solved, which has extremely high practical significance and economic value.

[0035] 5. The heating temperature control system in this application includes a controller, which realizes automatic and precise control of heating time and heating temperature through a pre-set software control program, with a high degree of automation and high work efficiency.

[0036] 6. The heating temperature control system is used in this application for automatic control, which can be remotely controlled, saving manpower and being safer; at the same time, according to the characteristics of different steel materials, the corresponding selection of the software program can easily achieve the applicability of a variety of materials to meet multi-functional and diversified needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the structure of the use status of the local annealing and residual removal equipment of the weld in this application.

[0038] Figure 2 It is a schematic diagram of a partial installation structure of the local annealing and residual removal equipment of the weld in this application.

[0039] Figure 3 It is a three-dimensional structural schematic diagram of the first mounting seat, the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat in the present application.

[0040] Figure 4 It is a three-dimensional structural schematic diagram of the first mounting seat, the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat in the present application from another perspective.

[0041] Figure 5 It is a schematic diagram of the structure of the device in this application when used for U-shaped ribs.

[0042] Figure 6 It is a schematic diagram of the structure of the device in this application when used for bulb flat steel ribs.

[0043] Figure 7 It is a schematic diagram of the internal structure of the first mounting seat, the second mounting seat, the first auxiliary mounting seat and the second auxiliary mounting seat in this application.

[0044] Figure 8 It is a graph showing the change in longitudinal residual stress before and after annealing in this application.

[0045] Fig. 9 It is a diagram of the change of transverse residual stress before and after annealing in this application.

[0046] In the figure: 10. Mobile power station; 20. Heating temperature control system; 30. First mounting seat; 31. Ear plate; 32. First auxiliary mounting seat; 33. Protective shell; 34. Steel frame; 35. Heat insulation cotton; 36. Fastener; 37. Heat insulation asbestos board; 40. Second mounting seat; 41. Second auxiliary mounting seat; 50. Heating plate; 60. A first driving member; 70. A second driving member; 80. Top plate; 90, longitudinal ribs; 100, rotating shaft; 101. Insulation board. DETAILED DESCRIPTION

[0047] The following is combined with Figure 1 -Attached Fig. 9 , further details of this application are given.

[0048] In this application, in order to solve the problem that a large number of cracks appear in the orthotropic steel bridge decks in service but are difficult to repair, the welds of the orthotropic steel bridge decks are heated and insulated after welding to ultimately achieve the effect of reducing residual stress and dehydrogenation.

[0049] This application is based on the residual stress detection of the corner welds of orthotropic steel bridge decks, and conducts a large number of modeling and real bridge tests on the causes of fatigue cracking of the top plate and longitudinal rib welds, the diaphragm and longitudinal rib welds, and the diaphragm openings. Through analysis, research, and testing, it is finally confirmed that the transverse residual stress of up to 200 MPa after welding induces cracks in the initial defects of the welds under the side effect of vehicle operation stress; at the same time, the longitudinal welding residual stress of up to 400 MPa (which has exceeded the yield strength of the parent material) is the main reason for the rapid expansion of cracks.

[0050] After clarifying that welding residual stress is the main cause of weld fatigue cracking, a large number of research and development of various residual elimination technologies were carried out, and it was finally confirmed that post-weld heat treatment of welds is the best method for residual elimination and dehydrogenation. On this basis, the relevant equipment for residual elimination and dehydrogenation for local heating and annealing of orthotropic steel bridge deck welds to reduce weld residual stress was developed, filling the gap in technical equipment for post-weld heat treatment of orthotropic steel bridge deck defects in service at home and abroad. After the relevant equipment and methods in this application were used to repair cracks in actual bridges, the effect was good. The post-weld residual longitudinal stress detection was reduced from an average of 400 MPa to about 120 MPa, and the transverse residual stress was reduced from 150 MPa to less than 100 MPa. No delayed cracks caused by hydrogen embrittlement occurred, and good social and economic benefits were achieved.

[0051] Specifically, refer to Figure 1 and Figure 2 As shown, the local annealing and residual removal equipment for the weld of the orthotropic steel bridge deck in this embodiment includes a mobile power station 10, a heating temperature control system 20, a first mounting seat 30 for abutting against the bottom of the orthotropic steel bridge top plate 80, and a second mounting seat 40 for abutting against the longitudinal rib 90 of the orthotropic steel bridge; one end of the second mounting seat 40 is mounted and connected to the first mounting seat 30, and a heating plate 50 is fixed on the side of the first mounting seat 30 and the second mounting seat 40 that are away from each other; the heating temperature control system 20 is electrically connected to the heating plate 50 and is used to control the heating temperature and time of the heating plate 50. The heating temperature control system 20 controls the heating temperature and time of the heating plate 50 by voltage, current size and power-on time. A temperature sensor can be set on the heating plate 50 to feedback the real temperature of the heating plate 50 in real time. The mobile power station 10 is used to provide energy and heating for the heating plate 50 and is electrically connected to the heating temperature control system 20. In this way, when the entire equipment is operated in a field environment, there is no need to set up additional wires, thereby meeting the use requirements of complex working conditions and reducing the use limitations of the entire equipment.

[0052] Reference Figure 3 and Figure 4As shown, the first mounting seat 30 and the second mounting seat 40 are both plate-shaped, and one end of the second mounting seat 40 is rotatably connected to one end of the first mounting seat 30 through a rotating shaft 100; the first mounting seat 30 and the second mounting seat 40 are connected with a first driving member 60 for driving both to move toward the direction of the orthogonal anisotropic steel bridge longitudinal rib 90; the first driving members 60 installed on the first mounting seat 30 and the second mounting seat 40 are at least two, and in this embodiment, as a preference, the first driving members 60 installed on the first mounting seat 30 and the second mounting seat 40 are both two, and the four first driving members 60 are distributed in a rectangular array; the first driving member 60 is a hydraulic rod or an electric push rod; an ear plate 31 corresponding to the first driving member 60 is fixed on the side surface close to the first mounting seat 30 and the second mounting seat 40, one end of the first driving member 60 is pinned to the corresponding ear plate 31, and the other end of the first driving member 60 is provided with a magnetic attraction structure, which can be an electromagnet or a permanent magnet. The above-mentioned multiple first driving members 60 can stably and reliably push the first mounting seat 30 and the second mounting seat 40 to move, and at the same time, the magnetic attraction structure at the end of the first driving member 60 is used to assist in clamping the first mounting seat 30 and the second mounting seat 40 between two adjacent longitudinal ribs 90, thereby ensuring the stable and reliable installation of the first mounting seat 30 and the second mounting seat 40, and also enabling the heating plate 50 to fit more closely with the orthogonal anisotropic steel bridge top plate 80 and the longitudinal ribs 90, thereby improving the heat conduction efficiency, reducing heat loss, and ensuring the heat treatment effect.

[0053] Reference Figure 3 and Figure 4 As shown, a second driving member 70 is provided between the first mounting seat 30 and the second mounting seat 40 for driving the second mounting seat 40 to swing on the first mounting seat 30, and the swing amplitude of the second mounting seat 40 is within the angle range of 90° to 105° between the second mounting seat 40 and the first mounting seat 30. Figure 5 and Figure 6 As shown, the second driving member 70 drives the second mounting seat 40 to swing, adapting to different shapes of longitudinal ribs 90, and ensuring that the heating plate 50 on the second mounting seat 40 is more closely attached to the side of the longitudinal rib 90, thereby ensuring the stability and reliability of local heating and improving the heat treatment effect. The heating plate 50 on the second mounting seat 40 swings within the above-mentioned angle range with the second mounting seat 40, which can meet the different welding angle change requirements for connecting different stiffening ribs such as U ribs, I ribs, L ribs, etc., with high overall versatility and convenient adjustment.

[0054] In this embodiment, the second driving member 70 is also a hydraulic rod or an electric push rod; the two ends of the second driving member 70 are respectively connected to the side surfaces close to the first mounting seat 30 and the second mounting seat 40. The second driving member 70 can automatically adjust the swing angle of the second mounting seat 40 according to pre-set programs and parameters, and lock itself after adjusting into place, thereby meeting the requirements of different longitudinal rib 90 shapes and ensuring its stability and reliability in use.

[0055] Reference Figure 3 and Figure 4 As shown, a first auxiliary mounting seat 32 for abutting against an orthogonal anisotropic steel bridge diaphragm is fixedly disposed at the end of the first mounting seat 30, and a second auxiliary mounting seat 41 for abutting against an orthogonal anisotropic steel bridge diaphragm is fixedly disposed at the end of the second mounting seat 40; a heating plate 50 is also fixedly disposed on the sides of the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 facing away from the first mounting seat 30 and the second mounting seat 40. Further, the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 are both triangular plates, and the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 are both perpendicular to the first mounting seat 30 and the second mounting seat 40 at the same time; when the first mounting seat 30 is perpendicular to the second mounting seat 40, the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 are relatively connected to form a rectangular plate structure; an insulation board 101 is also installed on one side of the first auxiliary mounting seat 32 or the second auxiliary mounting seat 41, and the insulation board 101 is fixed to one of the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 by screws, for example, the insulation board 101 1 is fixed to the first auxiliary mounting seat 32 by screws, and the other part of the insulation board 101 extends out of the first auxiliary mounting seat 32 toward the second auxiliary mounting seat 41, and there is a small gap between the side of the insulation board 101 and the side of the second auxiliary mounting seat 41; when the second auxiliary mounting seat 41 swings with the first mounting seat 30, the side of the insulation board 101 is opposite to the side of the second auxiliary mounting seat 41 and there is slight friction or no friction between the two; when the angle between the first mounting seat 30 and the second mounting seat 30 is an obtuse angle, the insulation board 101 can block the gap between the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41. The heating plate 50 on the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 rests on the orthogonal anisotropic steel bridge diaphragm to heat the relevant defective area, making it more widely used, and can heat treat multiple locations at the same time, with higher work efficiency.

[0056] The heating plate 50 in this embodiment is made of a customized ceramic electronic heating plate, and its length, width and angle are designed and customized according to the requirements of annealing and insulation of the steel bridge deck; Figure 7As shown, in the present application, the first mounting seat 30, the second mounting seat 40, the first auxiliary mounting seat 32 and the second auxiliary mounting seat 41 all include a protective shell 33 and a steel frame 34. The protective shell 33 is made of a steel plate with a thickness of 1 to 2 mm. The protective shell 33 is a sandwich structure and is filled with heat insulation cotton 35 in the protective shell 33. The thickness of the heat insulation cotton 35 is 10 to 20 mm. The steel frame 34 is located in the protective shell 33. The heating plate 50 is connected to the steel frame 34 through a fastener 36 and an insulating asbestos board 37 is fixed between the heating plate 50 and the protective shell 33. The fastener 36 can be a bolt, a rivet or a countersunk screw. Such a multi-layer insulation structure has a good insulation effect, can effectively improve the heating stability and reliability of the heating plate 50, reduce heat loss, and ensure the effect of heat treatment.

[0057] The present application also discloses a method for using a device for local annealing and removing residual welds of an orthotropic steel bridge deck, wherein the device for local annealing and removing residual welds of an orthotropic steel bridge deck is used to perform local annealing and removing residual welds of an orthotropic steel bridge deck; the method for using the device for local annealing and removing residual welds of an orthotropic steel bridge deck comprises the following steps: S1: Smooth surface: Mill or grind the top plate 80, diaphragm and rib plate defect welds of the orthotropic steel bridge to make the surface smooth; S2: Install and adjust the equipment: install the weld local annealing and residual removal equipment at the bottom of the top plate 80, the first driving member 60 pushes the first mounting seat 30 and the second mounting seat 40 to move toward the orthotropic steel bridge rib plate and hold it; the heating plate 50 on the first mounting seat 30 abuts against the bottom of the orthotropic steel bridge top plate 80, and the heating plate 50 on the first mounting seat 30 abuts against the orthotropic steel bridge rib plate; S3: Heat treatment: Select appropriate temperature control program and parameters, preset heating temperature and time, and perform heating annealing, residual dehydrogenation treatment on the weld; S4: Inspection: After the heat treatment is completed, the equipment is dismantled and then residual stress detection and acceptance are carried out.

[0058] The implementation principle is as follows: The equipment in this application is used to repair fatigue cracking of the welds between the longitudinal ribs 90 and the top plate 80, which are the most common defects in the orthotropic steel bridge decks in service. When in use, the equipment is installed at the bottom of the top plate 80, and the first driving member 60 pushes the first mounting seat 30 and the second mounting seat 40 to move toward the orthotropic steel bridge rib plate and hold it; the heating plate 50 on the first mounting seat 30 abuts against the bottom of the orthotropic steel bridge top plate 80, and the heating plate 50 on the first mounting seat 30 abuts against the orthotropic steel bridge rib plate; the heating temperature and heating time of the heating plate 50 are controlled by the heating temperature control system 20, so as to perform heat treatment on the weld to achieve the effect of eliminating welding residual stress, and at the same time improve the metallographic structure of the weld, thereby improving the mechanical properties, corrosion resistance and fatigue resistance of the weld.

[0059] As shown in Table 1, during the annealing process, since the annealing temperature peak is 600°C, the base material does not undergo austenite transformation, and martensite is a supersaturated solid solution of carbon in α-Fe. As the annealing process proceeds, element diffusion and element combination cause carbon and carbides to precipitate at the α-Fe grain boundaries, and the supersaturated state of carbon in α-Fe disappears, forming a mixed structure of α-Fe and carbides, namely bainite structure. During the annealing process, with the disappearance of martensitic structure, precipitation of carbon and carbides, dislocation migration, a small amount of plastic deformation, and uniform distribution of grains, the internal structure of the material changes, causing the deformation of internal stress to disappear, and the residual stress of the weld joint is reduced and released and presents a uniform distribution.

[0060] Serial number Annealing temperature / ℃ Insulation time / min Maximum heating rate ℃ / h Maximum cooling speed ℃ / h 1 600～620 25 220 280 2 550～570 180 220 280 3 500～520 360 220 280 Table 1 The present application is used to carry out local annealing heat treatment on the welding seams of orthotropic steel bridge decks in service. Through the heating plate in the relevant equipment, the outer side of the heating plate is completely fitted to the outer side of the rib plate and the welding corners on the left and right sides of the upper side with the most flat and uniform force. Compared with the existing technology, this achieves uniform annealing heat treatment of the rib plate butt welds, thereby more uniformly eliminating welding residual stress; the relevant equipment in the present application is easy to install and disassemble, has a high degree of automation, and has good heating and heat preservation effects; the entire equipment is easy to carry and can be reused, reducing production costs; the method in the present application is conducive to completing the post-weld annealing of orthotropic steel bridge decks, can shorten the construction period, save construction costs, effectively connect the construction processes, conform to the concept of green construction, and has strong practicality. The key technology of the annealing process has the advantages of high stress elimination rate and simple operation.

[0061] Reference Figure 8 and Fig. 9 As shown in the figure, based on the test data of residual stress changes before and after annealing obtained after thousands of actual bridge experiments, in this application, the transverse residual stress of the repaired weld is reduced by 75%, and the longitudinal residual stress is reduced by more than 80% after automatic heating, insulation, cooling and other process treatments are performed on the repaired weld. The hydrogen embrittlement phenomenon is basically eliminated, and the residual elimination effect is obvious, which solves the world's difficult problem of repeated cracking of in-service bridges in a short period of time after repair.

[0062] The heating temperature control system in this application includes a controller, which can realize automatic and precise control of heating time and heating temperature through a pre-set software control program, with high automation and high work efficiency. It can also be remotely controlled, saving manpower and being safer; at the same time, according to different steel characteristics, the software program can be easily selected to suit a variety of materials, such as orthotropic steel bridge deck materials of different yield strengths, such as 350, 370, 420, 620, etc., to set software programs corresponding to different heating temperatures and heating times, so that the corresponding automatic temperature control program can be quickly selected according to the pre-derived steel bridge material model to meet multi-functional and diversified needs.

[0063] The embodiments of this specific implementation are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. The same components are represented by the same figure marks. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A local annealing and residual removal equipment for welds of orthotropic steel bridge decks, characterized in that: It comprises a first mounting seat (30) for abutting against the bottom of an orthotropic steel bridge top plate (80) and a second mounting seat (40) for abutting against a longitudinal rib (90) of the orthotropic steel bridge; one end of the second mounting seat (40) is mounted and connected to the first mounting seat (30); The first mounting seat (30) and the second mounting seat (40) are connected to a first driving member (60) for driving the two to move toward the orthotropic steel bridge longitudinal rib (90); A heating plate (50) is fixedly provided on the side surfaces of the first mounting seat (30) and the second mounting seat (40) facing away from each other; The weld local annealing and residual removal equipment also includes a heating temperature control system (20), wherein the heating temperature control system (20) is electrically connected to the heating plate (50) and is used to control the heating temperature and time of the heating plate (50).

2. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 1 is characterized in that: The first mounting seat (30) and the second mounting seat (40) are both plate-shaped, and one end of the second mounting seat (40) is rotatably connected to one end of the first mounting seat (30) via a rotating shaft (100); at least two first driving members (60) are mounted on the first mounting seat (30) and the second mounting seat (40), and the first driving member (60) is a hydraulic rod or an electric push rod; an ear plate (31) corresponding to the first driving member (60) is fixed on the side surface of the first mounting seat (30) and the second mounting seat (40) close to each other, and one end of the first driving member (60) is pinned to the corresponding ear plate (31), and the other end of the first driving member (60) is provided with a magnetic attraction structure.

3. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 1 is characterized in that: A second driving member (70) is provided between the first mounting seat (30) and the second mounting seat (40) for driving the second mounting seat (40) to swing on the first mounting seat (30).

4. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 3 is characterized in that: The swing amplitude of the second mounting seat (40) is within the angle range of 90° to 105° between the second mounting seat (40) and the first mounting seat (30).

5. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 3 or 4, characterized in that: The first mounting seat (30) and the second mounting seat (40) are both plate-shaped, and one end of the second mounting seat (40) is rotatably connected to one end of the first mounting seat (30) via a rotating shaft (100); the second driving member (70) is a hydraulic rod or an electric push rod; and the two ends of the second driving member (70) are respectively connected to the side surfaces of the first mounting seat (30) and the second mounting seat (40) that are close to each other.

6. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 1, 2, 3 or 4, characterized in that: A first auxiliary mounting seat (32) for abutting against an orthotropic steel bridge diaphragm is fixedly provided at the end of the first mounting seat (30), and a second auxiliary mounting seat (41) for abutting against an orthotropic steel bridge diaphragm is fixedly provided at the end of the second mounting seat (40); the heating plate (50) is also fixedly provided on the side surfaces of the first auxiliary mounting seat (32) and the second auxiliary mounting seat (41) facing away from the first mounting seat (30) and the second mounting seat (40).

7. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 6 is characterized in that: The first auxiliary mounting seat (32) and the second auxiliary mounting seat (41) are both triangular plates, and the first auxiliary mounting seat (32) and the second auxiliary mounting seat (41) are both perpendicular to the first mounting seat (30) and the second mounting seat (40); when the first mounting seat (30) and the second mounting seat (40) are perpendicular, the first auxiliary mounting seat (32) and the second auxiliary mounting seat (41) are relatively connected to form a rectangular plate structure; A heat preservation plate (101) is also installed on one side of the first auxiliary mounting seat (32) or the second auxiliary mounting seat (41); when the angle between the first mounting seat (30) and the second mounting seat (40) is an obtuse angle, the heat preservation plate (101) is capable of blocking the gap between the first auxiliary mounting seat (32) and the second auxiliary mounting seat (41).

8. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 6 is characterized in that: The heating plate (50) is made of a ceramic electronic heating plate; the first mounting seat (30), the second mounting seat (40), the first auxiliary mounting seat (32) and the second auxiliary mounting seat (41) all include a protective shell (33) and a steel frame (34); the protective shell (33) is a sandwich structure and is filled with heat-insulating cotton (35); the steel frame (34) is located in the protective shell (33); the heating plate (50) is connected to the steel frame (34) via a fastening member (36) and a heat-insulating asbestos board (37) is fixed between the heating plate (50) and the protective shell (33).

9. The local annealing and residual removal equipment for welds of orthotropic steel bridge decks according to claim 1 is characterized in that: The weld local annealing and residual removal equipment also includes a mobile power station (10), wherein the mobile power station (10) is used to supply energy and heat the heating plate (50) and is electrically connected to the heating temperature control system (20).

10. A method for using a local annealing and residual removal device for welds of orthotropic steel bridge decks, characterized in that: The local annealing and residual removal equipment for welds as described in any one of claims 1 to 9 is used for local annealing and residual removal of welds; the method of use comprises the following steps: S1: Smoothing the surface: milling or grinding the top plate (80), diaphragm and rib plate defect welds of the orthotropic steel bridge to make the surface smooth; S2: Installing and adjusting the equipment: installing the weld local annealing and residual removal equipment on the bottom of the top plate (80), the first driving member (60) pushes the first mounting seat (30) and the second mounting seat (40) to move toward the orthotropic steel bridge rib plate and hold it; the heating plate (50) on the first mounting seat (30) abuts against the bottom of the orthotropic steel bridge top plate (80), and the heating plate (50) on the first mounting seat (30) abuts against the orthotropic steel bridge rib plate; S3: Heat treatment: Select appropriate temperature control program and parameters, preset heating temperature and time, and perform heating annealing, residual dehydrogenation treatment on the weld; S4: Inspection: After the heat treatment is completed, the equipment is dismantled and then residual stress detection and acceptance are carried out.

Images