CN107953043A - A kind of welding procedure of last furnace shell longitudinal seam - Google Patents
A kind of welding procedure of last furnace shell longitudinal seam Download PDFInfo
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- CN107953043A CN107953043A CN201711459700.7A CN201711459700A CN107953043A CN 107953043 A CN107953043 A CN 107953043A CN 201711459700 A CN201711459700 A CN 201711459700A CN 107953043 A CN107953043 A CN 107953043A
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- welding
- weld
- furnace shell
- seam
- longitudinal seam
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K33/00—Specially-profiled edge portions of workpieces for making soldering or welding connections; Filling the seams formed thereby
- B23K33/004—Filling of continuous seams
- B23K33/006—Filling of continuous seams for cylindrical workpieces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
- B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Arc Welding In General (AREA)
Abstract
The invention discloses a kind of welding procedure of last furnace shell longitudinal seam; pass through the combination of bonding machine and the improvement of welding tooling; the welding gun of carbon dioxide gas arc welding full set function device is clamped on automatic welding machine and proposes supporting welding technique; the weld crack on high-strength steel material can be effectively eliminated; so as to the welding structure for having obtained the weld seam of high quality and having stablized; fully meet the requirement of high-strength steel in actual use; and the welding procedure is easy to operate; cost Low investment expense is relatively low to meet live actual demand, and work efficiency is high.
Description
Technical field
The present invention relates to a kind of welding procedure that weld joints of blast furnace shell uses automatic welding machine welding, especially last furnace shell
The welding procedure of longitudinal seam.
Background technology
China has become world steel big country at present.The scale of blast furnace construction becomes hugeization trend, last furnace shell
Welding plate thickness it is also increasing, the workload of welding is increasing.Traditional last furnace shell maintenance uses manual welding, welds
Heavy workload, labor intensity is big, weld interval length, far from the requirement for meeting construction speed and construction quality.
2500m3Blast furnace is responsible for important function as the main ironmaking equipments of Ma Gang in the molten iron production of Ma Gang, wherein
The last furnace shell being welded online by steel plate is the equipment that must be replaced in blast furnace overhaul, is mainly used to fix cooling and sets
It is standby, seal furnace body, bear thermal stress and internal gas pressure etc. is, it is necessary to there is enough intensity.During blast furnace overhaul, last furnace shell
Welding quality and weld interval key effect, the weldering of all weld seams of steel plate of former horse steel last furnace shell are played to blast furnace maintenance
Connect and add carbon dioxide gas arc welding to weld using artificial manual arc, since welding job amount is big, by welding space, welding
Furnace shell heat-conductive body temperature and the limitation for encountering summer weather high temperature, during welding cannot more people operate at the same time, weld interval length, weldering
Quality is connect to be had a great influence by operating personnel's technical ability and physical efficiency.
The content of the invention
To solve the above problems, the present invention provides a kind of welding procedure of last furnace shell longitudinal seam, automatic welding is utilized
Pick the automatic soldering method of combined carbon dioxide gas shielded arc welding full set function device, and speed of welding is fast, and weld is accepted rate is high.
The concrete technical scheme of the present invention is as follows, a kind of welding procedure of last furnace shell longitudinal seam, the Welder
Skill step is：
1) welding equipment prepares, and the welding gun of carbon dioxide gas arc welding full set function device is clamped in automatic welding machine
On；According to site requirement, automatic welding machine clamping welding gun supporting rod restructuring is lengthened, is thickeied, and makes auxiliary steel plate；
2) weld preparation, carries out retaining wall on slope, longitudinal joint is X-type slope by the cut deal position to be welded that thickness is 45~80mm
Mouthful；Cut deal after finished edge is bent into work by design requirement, then assembling centering docking is positioned and anti-deformation tool
Synchronous fixed weldering；
3) weld preheating, in order to ensure that preheating temperature is uniform, heating unit, optional gas are arranged along inside and outside groove center
Heating or electrical heating, heating-up temperature will reach 100 DEG C；
4) weld：
A, first carries out the collar extension weld seam that unfixed anti-deformation pressing plate is cleared up in inspection of edge preparation again；
B, welding equipment is in place, and first coarse adjustment welding gun moves on to all adjusting rods among scale, in display screen in welding process
Upper fine tuning；
C, vertical seam from bottom to top weld, if the too small exchangeable nozzle of groove, the welding of prime coat is fused with mother metal, really
After the defects of recognizing weld layer flawless, slag inclusion, stomata, then weld the second layer；
D, mouth soldering seam grinding in being carried out after the completion of continuous three~tetra- layers of welding with ancillary equipment, while cut off anti-deformation pressure
Plate frock, installation auxiliary steel plate；
E, the weld seam after back chipping are integrally polished from bottom to top using angle grinder again, are confirmed without being beaten after any defect
Back welding connects, and after continuously welding two~tri- layers, carries out the inside and outside filling of mouth weld seam and capping and is symmetrically welded at the same time；
5) postweld heat preservation, postwelding are covered on weld seam with 20~30mm asbestos immediately, cover width >=40mm, and take compression
Measure, technique flaw detection is carried out after being cooled to room temperature.
Further, HCD500-6 automatic welding machines are selected in the step 1) welding equipment.
Further, 3~5mm of the step 1) auxiliary steel plate thickness, width 500mm, length is actual slightly larger than scene to weld
Seam measurement length, auxiliary steel plate are arranged on any sides of Edge Distance 50mm of longitudinal seam, are welded with furnace shell body.
Further, before b welding equipments are in place in the step 4), automatic welding machine is installed on auxiliary steel plate and is led
To mechanism, the walking mechanism track for coordinating automatic welding machine is horizontally mounted along groove, orbital distance groove center line is 320mm,
The lower part of groove can also make run-on tab, all removed again after waiting completion flaw detection to be welded qualified and aid in steel plates.
Further, if c faces of weld find obvious weld defect in the step 4), back chipping and use craft immediately
Electric arc welding rod is repaired.
Further, the ancillary equipment that d is selected in the step 4) is carbon arc air gouging or plasma gouge.
Further, when e welds capping in the step 4), groove face width<40mm is using individual layer capping, groove face
Width >=40mm uses multilayer capping.
Compared with prior art, beneficial effects of the present invention are：1) present invention uses HCD500-6 automatic welding machines first
The automatic soldering method of combined carbon dioxide gas shielded arc welding full set function device, and new Process is developed, applied to height
Stove furnace shell welds, and reference is provided for the thick plates of same material；
2) present invention substitutes conventional blast furnace welding to hold boilers and pressure vessel evidence obtaining welder, only needs general operative employee
Operated according to new process, simplify flow, improved work efficiency；
3) present invention substantially reduces labor intensity, and operating personnel only need on-line fine various process rules during welding, all
It can also rest when normal, change conventional welder ceaselessly armed operation；
4) the big slab level that welds of the present invention is smooth, uniform without any weld defect, especially shape beauty up to standard, compared with
The level being unable to reach toward manual welding；
5) reliable welding quality of the present invention is stablized, and has prevented various factors interference effect welding quality during manual welding, very
To the situation for large area occur and doing over again.
Figure of description
Fig. 1：Longitudinal seam groove front view in the present invention；
Fig. 2：Longitudinal seam groove top view in the present invention；
Fig. 3：Longitudinal seam groove graphics in the present invention；
Fig. 4：The two-sided vertical position welding schematic diagram of unit in the present invention；
Embodiment
With reference to Figure of description, the present invention is further described through.
Embodiment 1
A kind of welding procedure of last furnace shell longitudinal seam, welding procedure step are：
1) preparation of welding equipment
The various welding parameters of orbit adjusting (0~1100mm/min) vehicle with walking machine is passed through using HCD500-6 automatic welding machines
Structure, the welding gun of carbon dioxide gas arc welding full set function device is clamped on automatic welding machine, then is matched：L stops on a left side/R
The right side stops/C delays, swing speed, swing angle (0~10 ° of adjustable range), the speed of travel (0~1100mm/min), receive arc/non-
Welding/welding, adjust in, direction of travel, startup/stopping.Various positions speed of welding, each welding is adjusted in normal weld again
Data, the technique for comparing all welding acceptable qualities, the automatic welding machine after combination are finally reached the weldering of big slab last furnace shell
Connect requirement.
Original HCD500-6 automatic welding machines clamping welding gun supporting rod is shorter, and when welding cannot meet live longitudinal joint 200mm
Weld below, demand is welded according to actual field, now not only all restructuring adds by all automatic welding machines clamping welding gun supporting rod
Long and thickening.Bottom but also the welding gun stable operation clamping can be soldered to when so welding.
Original HCD500-6 automatic welding machines guiding mechanism, it is impossible to meet that live longitudinal joint clamping welding gun is welded to top, therefore
Steel plate is aided in using 3~5mm of thickness, width 500mm, auxiliary steel plate length goes out greatly 300mm than live actual welds measurement length, will
Auxiliary steel plate is arranged on any sides of Edge Distance 50mm of longitudinal seam, is welded with bottom furnace shell body.So both preferably solve
Weld seam both sides cold-water wall hole of having determined influences welding automatic vehicle and cannot climb Welding Problems, and can allow the steady mistake of automatic welding carriage
Cross and be welded in place.
2) weld preparation, as shown in Figure 1, Figure 2, shown in Fig. 3, groove is carried out by the cut deal position to be welded that thickness is 45~80mm
Processing, longitudinal joint is X-type groove；Cut deal after finished edge is bent into work by design requirement, assembling centering docking, then carries out
Positioning and anti-deformation tool synchronously fixed weldering.
3) weld preheating, in order to ensure that preheating temperature is uniform, heating unit, optional gas are arranged along inside and outside groove center
Heating or electrical heating, heating-up temperature will reach 100 DEG C.
Preheated in the present embodiment using heated by gas method, making bend pipe burner along groove is distributed in inside and outside groove
The heart, starts to weld when temperature reaches 100 DEG C or so, has to ensure that temperature is uniform, when site environment temperature can more than 30 DEG C
Without preheated weld.
4) weld：Vertical position welding X-type groove (longitudinal joint for referring to furnace shell) cylindrical tube, each section welds on platform for making to be completed
Transport the group docking that furnace body carries out circumferential weld again afterwards.
A, first carries out the collar extension weld seam that unfixed anti-deformation pressing plate is cleared up in inspection of edge preparation again, includes the surface of tack weld
Grinding；
B, HCD500-6 automatic welding machines and carriage walking track are installed on auxiliary steel plate includes the guiding of trolley technological transformation
Mechanism, the lower part of groove, which is such as had ready conditions, makes run-on tab, is all removed again after waiting completion flaw detection to be welded qualified and aids in steel plate；Weldering
It is in place to connect equipment, first coarse adjustment welding gun moves on to all adjusting rods among scale, fine tuning on a display screen in welding process.
C, vertical seam from bottom to top welds, if the too small exchangeable nozzle of groove, nozzle 6~20mm of specification, the welding of prime coat
It is fused with mother metal, after the defects of confirming weld layer flawless, slag inclusion, stomata, then weld the second layer.If face of weld is sent out
Now obvious weld defect back chipping and use manual electric arc welding E5015 welding rod repairings immediately.
Continuously welded because of multilayer and have to ensure interlayer temperature in the range of 150 ° or so, and using temperature measurer per hour
Survey once, make a record.
D, mouth soldering seam grinding in being carried out after the completion of continuous three~tetra- layers of welding with ancillary equipment, while cut off anti-deformation pressure
Plate frock, installation auxiliary steel plate；Ancillary equipment is carbon arc air gouging or plasma gouge, selects carbon arc air gouging in the present embodiment
ZX5-630。
E, the weld seam after back chipping are integrally polished from bottom to top using angle grinder again, are confirmed without being beaten after any defect
Back welding connects, and after continuously welding two~tri- layers, carries out the inside and outside filling of mouth weld seam and capping and is symmetrically welded at the same time.Capping layer will not only be protected
Demonstrate,prove enough thickness and be higher by furnace body mother metal, and ensure overall weld seam without any weld defect.In addition regulation groove face is wide without exception
Degree<40mm uses multilayer capping using individual layer capping, groove face width >=40mm, as shown in Figure 4.
5) postweld heat preservation, postwelding are covered on weld seam with 20~30mm asbestos immediately, cover width >=40mm, and take compression
Measure, technique flaw detection is carried out after being cooled to room temperature.
Mainly welded in the present embodiment using HCD500-6 automatic welding machines welding method, connect welding machine Nb-500P numbers
(back root cleaning uses carbon arc air gouging ZX5-630 and plasma gouge LGK- for the pulse gas-shielded weldering of wordization and other ancillary equipments
100MA).In addition HT400D Digital Control contravariant craft DC welder is selected to be used for soldering and local route repair end to end；This reality
Apply the welding material in example：Flux-cored wire SWE71.1 ￠ 1.2mm.
The welding process items technical parameter of the present embodiment is as follows：
Using the welding procedure of the present invention, the weld crack on high-strength steel material can be effectively eliminated, so as to obtain height
The weld seam of quality and the welding structure stablized, fully meet the requirement of high-strength steel in actual use, and the welding procedure is grasped
Make simplicity, cost Low investment expense is relatively low to meet live actual demand, and work efficiency is high.
More than, it is only presently preferred embodiments of the present invention, but protection scope of the present invention is not limited thereto, and it is any to be familiar with sheet
Those skilled in the art the invention discloses technical scope in, the change or replacement that can readily occur in should all be covered
Within protection scope of the present invention.Therefore, protection scope of the present invention should be subject to the protection domain that claim is defined.
Claims (7)
1. a kind of welding procedure of last furnace shell longitudinal seam, it is characterised in that the welding procedure step is：
1) welding equipment prepares, and the welding gun of carbon dioxide gas arc welding full set function device is clamped on automatic welding machine；
According to site requirement, automatic welding machine clamping welding gun supporting rod restructuring is lengthened, is thickeied, and makes auxiliary steel plate；
2) weld preparation, carries out retaining wall on slope, longitudinal joint is X-type groove by the cut deal position to be welded that thickness is 45~80mm；Will
Cut deal after finished edge bends work by design requirement, and assembling centering docking, then carries out positioning and anti-deformation tool is synchronous
Fixed weldering；
3) weld preheating, in order to ensure that preheating temperature is uniform, heating unit, optional gas heating are arranged along inside and outside groove center
Or electrical heating, heating-up temperature will reach 100 DEG C；
4) weld：
A, first carries out the collar extension weld seam that unfixed anti-deformation pressing plate is cleared up in inspection of edge preparation again；
B, welding equipment is in place, and first coarse adjustment welding gun moves on to all adjusting rods among scale, thin on a display screen in welding process
Adjust；
C, vertical seam from bottom to top weld, if the too small exchangeable nozzle of groove, the welding of prime coat is fused with mother metal, confirms weldering
After the defects of connecing a layer flawless, slag inclusion, stomata, then weld the second layer；
D, mouth soldering seam grinding in being carried out after the completion of continuous three~tetra- layers of welding with ancillary equipment, while cut off anti-deformation pressing plate work
Dress, installation auxiliary steel plate；
E, the weld seam after back chipping are integrally polished from bottom to top using angle grinder again, are confirmed without carrying out backing welding after any defect
Connect, after continuously welding two~tri- layers, carry out the inside and outside filling of mouth weld seam and capping and be symmetrically welded at the same time；
5) postweld heat preservation, postwelding are covered on weld seam with 20~30mm asbestos immediately, cover width >=40mm, and take compression to arrange
Apply, technique flaw detection is carried out after being cooled to room temperature.
A kind of 2. welding procedure of last furnace shell longitudinal seam according to claim 1, it is characterised in that the step
1) HCD500-6 automatic welding machines are selected in welding equipment.
3. the welding procedure of a kind of last furnace shell longitudinal seam according to claim 1 or 2, it is characterised in that described
3~5mm of step 1) auxiliary steel plate thickness, width 500mm, length are slightly larger than live actual welds and measure length, and auxiliary steel plate is set
In any sides of Edge Distance 50mm of longitudinal seam, welded with furnace shell body.
A kind of 4. welding procedure of last furnace shell longitudinal seam according to claim 1, it is characterised in that the step
4) before b welding equipments are in place in, automatic welding machine and guiding mechanism are installed on auxiliary steel plate, cooperation is horizontally mounted certainly along groove
The walking mechanism track of dynamic bonding machine, orbital distance groove center line is 320mm, and the lower part of groove can also make run-on tab, etc.
It is to be welded to complete all to remove auxiliary steel plate again after flaw detection is qualified.
A kind of 5. welding procedure of last furnace shell longitudinal seam according to claim 1, it is characterised in that the step
If 4) c faces of weld find obvious weld defect in, back chipping and use welding bar for hand electric arc-welding repairing immediately.
A kind of 6. welding procedure of last furnace shell longitudinal seam according to claim 1, it is characterised in that the step
4) ancillary equipment that d is selected in is carbon arc air gouging or plasma gouge.
A kind of 7. welding procedure of last furnace shell longitudinal seam according to claim 1, it is characterised in that the step
4) when e welds capping in, groove face width<40mm uses multilayer capping using individual layer capping, groove face width >=40mm.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201711459700.7A CN107953043A (en) | 2017-12-28 | 2017-12-28 | A kind of welding procedure of last furnace shell longitudinal seam |
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| CN201711459700.7A CN107953043A (en) | 2017-12-28 | 2017-12-28 | A kind of welding procedure of last furnace shell longitudinal seam |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112935479A (en) * | 2021-03-25 | 2021-06-11 | 安徽马钢设备检修有限公司 | Welding device and repairing process for large wheel fixing table base fracture |
| CN113070556A (en) * | 2021-03-25 | 2021-07-06 | 安徽马钢设备检修有限公司 | Rapid welding repair structure and repair process for foundation connecting screw of large hydraulic press |
| CN115365692A (en) * | 2022-08-30 | 2022-11-22 | 阜阳安固锅炉压力容器制造有限公司 | Welding method for preventing welding seam from cracking |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112935479A (en) * | 2021-03-25 | 2021-06-11 | 安徽马钢设备检修有限公司 | Welding device and repairing process for large wheel fixing table base fracture |
| CN113070556A (en) * | 2021-03-25 | 2021-07-06 | 安徽马钢设备检修有限公司 | Rapid welding repair structure and repair process for foundation connecting screw of large hydraulic press |
| CN115365692A (en) * | 2022-08-30 | 2022-11-22 | 阜阳安固锅炉压力容器制造有限公司 | Welding method for preventing welding seam from cracking |
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