CN115948647A

CN115948647A - Heat treatment equipment for on-site butt weld of U rib of steel box girder top plate

Info

Publication number: CN115948647A
Application number: CN202310097411.6A
Authority: CN
Inventors: 王洪福; 安迪; 汪春民; 李乐
Original assignee: China Construction Industrial and Energy Engineering Group Co Ltd; China Construction Equipment and Engineering Co Ltd
Current assignee: China Construction Industrial and Energy Engineering Group Co Ltd; China Construction Equipment and Engineering Co Ltd
Priority date: 2023-02-10
Filing date: 2023-02-10
Publication date: 2023-04-11
Anticipated expiration: 2043-02-10
Also published as: CN115948647B

Abstract

The invention discloses heat treatment equipment for a U rib field butt weld of a steel box girder top plate, which comprises a U rib heating and heat preservation structure, wherein the U rib heating and heat preservation structure is positioned at the bottom of a U rib and can play a role in heat preservation when the spot butt weld of the U rib is subjected to heat treatment, the U rib heating and heat preservation structure comprises a metal shell, an electromagnet and a metal connecting plate, the front side and the rear side of the bottom of the metal shell are respectively connected with the metal connecting plate used for fixing the metal shell to the bottom of the U rib in a spot welding mode, and the left side and the right side above the metal shell are respectively provided with the electromagnet capable of temporarily fixing the metal shell to the bottom of a panel above the U rib. According to the invention, through the U-rib heating and heat-insulating structure and the electric heating sheet and the metal shell, the outer side surface of the electric heating sheet can be completely attached to the welding corners of the outer side, the left side and the right side above the U-rib by the flattest and uniform force, so that the U-rib butt welding seam is uniformly annealed, and the stress is more uniformly eliminated.

Description

Heat treatment equipment for on-site butt weld of U rib of steel box girder top plate

Technical Field

The invention relates to the technical field of steel box girder splicing welding heat treatment, in particular to heat treatment equipment for a steel box girder top plate U rib on-site butt welding seam.

Background

The orthotropic steel bridge deck structure is a main structural form of a bridge deck of a large-span steel bridge due to light dead weight and high rigidity, a large number of welding seams exist in the traditional orthotropic bridge deck structure, welding deformation is easy to generate, welding residual stress is generated in the welding seams and a heat affected zone, weak parts of metallographic structures and mechanics of materials are formed, the defects of deformation, early cracking, stress corrosion, fatigue fracture, brittle fracture and the like of the steel bridge deck during service are caused, and the service life of the structure is directly influenced;

the technology can only partially eliminate the residual stress generated by factory processing welding, in the production and processing process of the orthotropic steel bridge deck, in order to facilitate the transportation and field installation of the steel box girder, the structure is generally divided into sections with certain length, U rib embedding sections with certain length are reserved between the adjacent sections, the U rib embedding sections are respectively connected with the U ribs of the adjacent sections to realize assembly, and the butt welding seams of the U ribs still have the residual stress for eliminating the welding;

particularly for the on-site welding seam of the U rib of the top plate, because overhead welding is adopted in the on-site welding process and is influenced by the on-site welding condition, the welding quality is difficult to ensure, and during the service period of the steel bridge, fatigue cracks which are initiated from the welding seam of the longitudinal rib bottom plate and expanded to the web plate of the longitudinal rib along the welding seam often appear, so that the longitudinal rib splicing welding seam is one of the key focus details of fatigue resistance design and evaluation in the actual engineering;

aiming at an on-site post-welding heat treatment mechanism of a fillet weld of a header connecting pipe of a thermal power plant disclosed by the No. CN207176027U, a first flexible ceramic heater which covers the preset axial length of an alloy steel header cylinder and the outer surface area of the alloy steel header cylinder outside the bottom area of a taper fillet weld to be treated in the length range is arranged; the second flexible ceramic heater covers the preset axial length of the alloy steel small pipe, the area of the outer surface of the alloy steel small pipe within the length range and the whole conical outer surface of the conical fillet weld to be processed; the alloy steel header cylinder temperature thermocouple, the taper angle weld joint temperature thermocouple and the alloy steel small pipe temperature thermocouple are respectively arranged on the alloy steel header cylinder, the taper angle weld joint to be processed and the outer surface of the alloy steel small pipe; by adopting the heat treatment mechanism of the utility model, not only can the real and accurate temperature of different parts be obtained, the welding seam can be effectively heat treated, but also the phenomenon of overburning of the small pipe can be prevented;

in the above-mentioned comparison document, the alloy steel header cylinder, the taper fillet weld and the alloy steel tubule are locally measured by the existing thermocouple, so as to improve the real and accurate temperature of different parts during heat treatment, and when the alloy steel header cylinder, the taper fillet weld and the alloy steel tubule are subjected to temperature rise heat treatment, the flexible ceramic heater is wrapped on the alloy steel header cylinder, the taper fillet weld and the alloy steel tubule by winding the iron wire, so as to complete the heat treatment of the alloy steel header cylinder, the taper fillet weld and the alloy steel tubule, and the scheme has two problems: according to the scheme, the flexible ceramic heater is only wrapped on the outer surfaces of the alloy steel header cylinder, the taper fillet weld and the alloy steel small pipe only through iron wires, after the iron wires wrap the flexible ceramic heater, on one hand, the heating dissipation speed of the flexible ceramic heater is too high, so that when the heating heat treatment is carried out on the outer sides of the alloy steel header cylinder, the taper fillet weld and the alloy steel small pipe, the efficiency is too low, meanwhile, the outer sides of the alloy steel header cylinder, the taper fillet weld and the alloy steel small pipe cannot reach the preset high temperature for heat treatment, on the other hand, if the flexible ceramic heater is wrapped through the iron wires, the tightness of the flexible ceramic heater attached to the alloy steel header cylinder, the taper fillet weld and the outer surface of the alloy steel small pipe is different, so that the uniformity of heat treatment of all parts is difficult to improve, in addition, the mode of fixing the flexible ceramic heater through the iron wires is not convenient for operators to detach the equipment, so that the workload of the operators is increased, the time is also consumed, and meanwhile, the local heat treatment operation of a longer steel header beam butt joint technology problem of a U-rib welding seam on-spot is inconveniently provided.

Disclosure of Invention

The invention aims to provide heat treatment equipment for a field butt weld of a U rib of a top plate of a steel box girder, and aims to solve the problem of poor stability of local heat treatment operation of a field splicing weld of a longer steel box girder in the background art.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a thermal treatment equipment to on-spot butt weld of steel box girder roof U rib, is located U rib bottom and can play the U rib heating insulation construction of heat preservation effect when its on-the-spot butt weld department heat treatment, U rib heating insulation construction includes metal casing, electro-magnet and metal connecting plate, both sides all are connected with the metal connecting plate that is used for rather than the fixed U rib bottom of spot welding around the metal casing bottom, the electro-magnet that can fix temporarily in U rib top panel bottom to metal casing is all installed to the both sides about the metal casing top, U rib heating insulation construction left side is connected with the temperature control box that can play the control by temperature change operation to it.

In a further embodiment, the U-rib heating and heat-insulating structure further comprises electric heating sheets attached to the outer surface of the U rib and welding corners on the left side and the right side above the outer surface of the U rib, thermocouples used for measuring the temperature of the outer surface of the U rib during heat treatment are distributed on the inner side of each electric heating sheet in an array mode, a heat-insulating layer is coated on the outer side of each electric heating sheet, and the heat-insulating layer is located on the inner side of the metal shell.

In a further embodiment, the cross-sectional shape of the electric heating sheet is the same as the cross-sectional shape of the U-rib and the metal housing.

In a further embodiment, the upper part of the electromagnet is attracted with the panel at the top of the U-shaped rib.

In a further embodiment, the metal connecting plate fixes the metal shell and the U-rib by spot welding.

In a further embodiment, the temperature control box is connected with the U-rib heating and heat preservation structure through a lead.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the invention, the U-rib heating and heat-insulating structure is arranged, and the outer side surface of the electric heating sheet can be completely attached to the outer side of the U rib and the welding corners at the left side and the right side above the U rib by the aid of the electric heating sheet and the metal shell with the flattest and uniform force;

2. the invention is provided with the heat-insulating layer and the connecting plate, temperature emission can be placed in the heat treatment process of the heated electric heating sheet and the U rib through the heat-insulating layer to achieve the effect of heat insulation and temperature locking, the problem that the U rib heating and heat insulation structure is difficult to fix on the outer side of the U rib due to magnetic failure caused by magnetic decline caused by temperature rise in the annealing process of the electromagnet through the temporary fixing mode of spot welding of the connecting plate and the bottom of the U rib is solved, the reliable stability of the equipment in the using process is realized, meanwhile, the U rib at the position can be conveniently disassembled by an operator after the heat treatment is completed, compared with the prior art, the equipment can more conveniently realize the local annealing treatment of the on-site butt welding seam of the U rib of the steel box girder bridge, and the integral stability and convenience are improved.

Drawings

FIG. 1 is a schematic structural diagram of a heat treatment apparatus for an on-site butt weld of a U rib of a top plate of a steel box girder according to a preferred embodiment of the present invention;

FIG. 2 is a schematic view of the mounting structure of the electromagnet and the metal housing shown in FIG. 1;

fig. 3 is a schematic view of an installation structure of the insulating layer and the electric heating sheet shown in fig. 1.

In the figure: 1. a U-rib heating and heat-insulating structure; 11. an electrical heating sheet; 12. a thermocouple; 13. a heat-insulating layer; 14. a metal housing; 15. an electromagnet; 16. a metal connecting plate; 2. a temperature control box; 21. and (4) conducting wires.

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 only a part of the embodiments of the present invention, and not all of the 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 protection scope of the present invention.

Referring to fig. 1-3, an embodiment of the present invention is shown: a heat treatment device for a U-rib field butt weld of a steel box girder top plate comprises a U-rib heating and heat insulation structure 1, an electric heating piece 11, a thermocouple 12, a heat insulation layer 13, a metal shell 14, an electromagnet 15, a metal connecting plate 16, a temperature control box 2 and a lead 21, wherein the U-rib heating and heat insulation structure 1 is positioned at the bottom of a U rib and can play a heat insulation effect when the U-rib field butt weld is subjected to heat treatment, the U-rib heating and heat insulation structure 1 comprises the metal shell 14, the electromagnet 15 and the metal connecting plate 16, the metal connecting plate 16 used for fixing the metal shell 14 at the bottom of the U rib in a spot welding mode is connected to the front side and the rear side of the bottom of the metal shell 14, the electromagnet 15 capable of temporarily fixing the metal shell 14 at the bottom of a panel above the U rib is installed on the left side and the right side of the metal shell 14, and the temperature control box 2 capable of playing a temperature control operation for the U-rib heating and heat insulation structure 1 is connected to the left side.

Examples

Referring to fig. 1-3, the U-rib heating and heat insulating structure 1 further includes electrical heating sheets 11 attached to the outer surface of the U-rib and the welding corners on the left and right sides above the outer surface of the U-rib, thermocouples 12 for measuring temperature of the outer surface of the U-rib during heat treatment are distributed in an array on the inner side of the electrical heating sheets 11, an insulating layer 13 is coated on the outer side of the electrical heating sheets 11, the insulating layer 13 is located on the inner side of a metal shell 14, the cross-sectional shape of the electrical heating sheets 11 is the same as that of the U-rib and the metal shell 14, the upper side of an electromagnet 15 and a panel on the top of the U-rib are arranged in an attracting manner, a metal connecting plate 16 fixes the metal shell 14 and the U-rib by spot welding, a temperature control box 2 is connected with the U-rib heating and heat insulating structure 1 through a lead 21, heat treatment equipment with corresponding size is selected for the U-ribs of different types at first, and then the U-rib heating and heat insulating structure 1 and the metal shell 14 are installed on the outer side below the U-rib, then, under the condition that the electromagnet 15 is electrified to generate magnetism, the panel above the electromagnet 15 and the panel above the U-shaped rib are attracted to each other for temporary fixing, as the U-shaped rib heating and heat preserving structure 1 is mainly formed by assembling an electric heating sheet 11, thermocouples 12, a heat preserving layer 13, a metal shell 14, the electromagnet 15 and a metal connecting plate 16, the heat preserving layer 13 is arranged on the inner side of the metal shell 14, the electric heating sheet 11 is connected to the outer side of the heat preserving layer 13, the thermocouples 12 are distributed on the outer side of the electric heating sheet 11 in an array manner, the electric heating sheet 11 is attached to the welding corners of the outer side, the left side and the right side above the U-shaped rib, the upper ends of the two sides of the metal connecting plate 16 on the front side and the rear side of the bottom of the metal shell 14 are fixedly connected with the bottom of the U-shaped rib in a spot welding manner, then the electric heating sheet 11 is heated to a preset temperature by matching with a lead 21 through a temperature control box 2, and the heat preserving heat and insulating heat for the heated temperature by matching with the heat preserving heat layer 13, the annealing temperature is tracked and monitored through the thermocouple 12, the arrangement of the structure is compared with a comparison file in the background technology, the outer side surface of the electric heating sheet 11 can be completely attached to the outer side of the U rib and welding corners at the left side and the right side above the U rib by the flattest and uniform force, so that the annealing heat treatment on the butt welding seam of the U rib is uniformly carried out, the stress is uniformly eliminated, in addition, the heat insulation and temperature locking effects on the heated electric heating sheet 11 and the U rib can be achieved through the heat insulation layer 13, meanwhile, the local annealing treatment on the spot butt welding seam of the U rib of the steel box girder bridge can be conveniently realized, the defect that the magnetism is invalid due to the fact that the ferromagnetism of the electromagnet 15 rises due to the temperature in the annealing process is reduced is overcome through the temporary fixing mode of spot welding at the bottom of the connecting plate and the U rib, and the reliable fixing of the device in the using process is realized.

The working principle is as follows: as shown in figures 1-3, firstly, heat treatment equipment with corresponding size is selected for U ribs of different types, then a U rib heating and heat preservation structure 1 and a metal shell 14 are installed on the outer side below the U ribs, then under the condition that the electromagnet 15 is electrified to generate magnetism, the upper side of the electromagnet 15 and a panel above the U ribs are attracted to each other for temporary fixation, because the U rib heating and heat preservation structure 1 is mainly formed by assembling an electric heating sheet 11, a thermocouple 12, a heat preservation layer 13, the metal shell 14, the electromagnet 15 and a metal connecting plate 16, the inner side of the metal shell 14 is provided with the heat preservation layer 13, the outer side of the heat preservation layer 13 is connected with the electric heating sheet 11, the thermocouples 12 are distributed on the outer side of the electric heating sheet 11 in an array manner, the electric heating sheet 11 is attached to the outer side of the U ribs and the welding corners on the left side and the right side above, in addition, the upper ends on two sides of the metal connecting plates 16 on the front side and the back side of the bottom of the metal shell 14 are fixedly connected with the bottom of the U ribs in a spot welding manner, then, the temperature control box 2 is matched with the lead 21 to heat the electric heating sheet 11 to a preset temperature, the heat preservation layer 13 is matched to preserve heat and insulate heat of the heated temperature, the annealing temperature is tracked and monitored by the thermocouple 12, compared with a comparison document in the background technology, the structure can completely adhere to the welding corners on the outer side, the left side and the right side of the U rib and above the U rib by the outer side surface of the electric heating sheet 11 with the flattest and uniform force, so that the annealing heat treatment of the butt welding seam of the U rib can be uniformly carried out, the stress can be more uniformly eliminated, in addition, the effect of preserving heat and locking the temperature of the heated electric heating sheet 11 and the U rib can be achieved by the heat preservation layer 13, meanwhile, the equipment can conveniently realize the local annealing treatment of the butt welding seam of the U rib of the steel box girder bridge on site, and the temporary fixing mode of spot welding with the bottom of the U rib of the connecting plate, the defect that the magnetism of the electromagnet 15 is invalid due to the fact that the temperature rises and the ferromagnetism drops in the annealing process is overcome, and the device is reliably fixed in the using process, so that a series of work is completed.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. The utility model provides a thermal treatment equipment to on-spot butt weld of steel box girder roof U rib, is including being located U rib bottom can play heat preservation effect's U rib heating insulation construction (1) when its on-the-spot butt weld department thermal treatment, U rib heating insulation construction (1) includes metal casing (14), electro-magnet (15) and metal connecting plate (16), both sides all are connected with around metal casing (14) bottom and are used for metal connecting plate (16) of its fixed U rib bottom of spot welding, electro-magnet (15) that can fix temporarily in U rib top panel bottom to metal casing (14) are all installed to both sides about metal casing (14) top, U rib heating insulation construction (1) left side is connected with temperature control box (2) that can play the control by temperature change operation to it.

2. The heat treatment equipment for the on-site butt weld of the U rib of the top plate of the steel box girder according to claim 1, is characterized in that: u rib heating insulation construction (1) is still including laminating electrical heating piece (11) at U rib surface and top left and right sides fillet weld, electrical heating piece (11) medial surface array distribution has thermocouple (12) that are used for U rib surface to play the temperature measurement effect when thermal treatment, the cladding of electrical heating piece (11) outside has heat preservation (13), heat preservation (13) are located metal casing (14) medial surface.

3. The heat treatment equipment for the on-site butt weld of the U rib of the top plate of the steel box girder as claimed in claim 2, wherein: the cross-sectional shape of the electric heating sheet (11) is the same as that of the U-shaped rib and the metal shell (14).

4. The heat treatment equipment for the on-site butt weld of the U rib of the top plate of the steel box girder as claimed in claim 2, wherein: the upper part of the electromagnet (15) and the panel at the top of the U rib are arranged in an attracting mode.

5. The heat treatment equipment for the on-site butt weld of the U rib of the top plate of the steel box girder as claimed in claim 2, wherein: the metal connecting plate (16) fixes the metal shell (14) and the U rib by spot welding.

6. The heat treatment equipment for the on-site butt weld of the U rib of the top plate of the steel box girder according to claim 1, is characterized in that: and the temperature control box (2) is connected with the U-rib heating and heat-insulating structure (1) through a lead (21).