CN111331323A - Welding process for trunnion block of converter backing ring - Google Patents
Welding process for trunnion block of converter backing ring Download PDFInfo
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- CN111331323A CN111331323A CN202010201402.3A CN202010201402A CN111331323A CN 111331323 A CN111331323 A CN 111331323A CN 202010201402 A CN202010201402 A CN 202010201402A CN 111331323 A CN111331323 A CN 111331323A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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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
- 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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Abstract
A welding process for trunnion blocks of converter trunnion rings belongs to the technical field of manufacturing methods of converter trunnion rings, and is used for welding trunnions, inner side plates and outer side plates of the trunnion blocks of the converter trunnion rings. The trunnion block is manufactured according to the process, the manufacturing period can be saved by 35 days, and the processing cost can be saved by about 8 ten thousand yuan. The invention is the pioneer of the manufacturing process of the trunnion block of the converter trunnion ring, breaks through the traditional process flow, adopts a unique welding method, effectively reduces the welding stress and controls the welding deformation, ensures the welding quality of the two trunnion blocks, and can finish the annealing after welding without entering an annealing furnace. The welding process can solve the problems of long production cycle and high manufacturing cost of the converter backing ring caused by the traditional process.
Description
Technical Field
The invention relates to a welding process of a trunnion block of a converter trunnion ring, belonging to the technical field of manufacturing methods of converter trunnion rings.
Background
The converter backing ring is an important part of a converter, the backing ring is composed of two fan-shaped sections and two trunnion blocks, the fan-shaped sections are of a welded structure, the trunnion blocks are of a forge welding structure, the fan-shaped sections and the trunnion blocks are welded into the backing ring through four interfaces, and the backing ring is composed of an upper cover plate, a lower cover plate, an inner plate and an outer plate in a welded mode. The difficulty in manufacturing the trunnion ring is to ensure the coaxiality of the two trunnions, which needs to be realized through a welding process.
During the welding process, welding deformation is prevented first. Due to the limitation of the shape and the size of the backing ring, the coaxiality of the two trunnions cannot be guaranteed by integral processing, and the coaxiality of the two trunnion blocks after the backing ring is welded can be guaranteed to be less than or equal to 1mm only by controlling the welding deformation of a plurality of welding lines of the butt joint of the sector section and the trunnion block after the two trunnion blocks are subjected to finish machining. The welding stress is secondly taken into account. The structure of the trunnion ring is complex, the thicknesses of the upper cover plate, the lower cover plate and the web plate are large, the filling amount of the butt joint is large, the welding deformation rule is difficult to determine, and the whole stress relief treatment cannot be carried out after the trunnion ring is welded. Therefore, when the backing ring and the trunnion block are welded, welding stress is effectively reduced by formulating a reasonable welding process, and the control of welding deformation is the key for manufacturing the backing ring.
At present, the structure of trunnion block in the backing ring is box type mechanism, and the production of trunnion block needs to carry out the integral welding with trunnion, inside and outside lateral plate and upper and lower apron and deep floor in the box. The traditional manufacturing process method is that after the trunnion is roughly machined, the trunnion, the inner and outer side plates, the upper and lower cover plates and the lacing wires in the cavity are integrally assembled and then integrally welded. Because this structure is the box structure, pay attention to the heat input back in the welding process, can not take place too big deformation basically, comparatively easy production. And carrying out integral annealing after welding is finished, and processing according to the processing precision requirement on the trunnion in the drawing after annealing is finished to meet the drawing requirement. The traditional process mainly aims to ensure the dimensional tolerance of a final workpiece through processing, meet the requirements of drawings, reduce the difficulty of a welding process and have a longer production period. The trunnion is transferred from a forging workshop to a machining workshop for rough machining, then transferred to a welding workshop, transferred to a heat treatment workshop after the welding workshop is finished, transferred back to the machining workshop after the heat treatment is finished, and transferred back to the welding workshop for carrying out integral trial assembly on the trunnion ring after the machining workshop is finished, so that the process is very long, the transfer times are very many, and very much time and cost are wasted. With the development of production, the current production scheme is far from meeting the market demand, and it is necessary to change the current traditional manufacturing process and adopt a new process and method to manufacture the trunnion ring.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a welding process for trunnion blocks of converter trunnion rings, which can effectively control welding stress and welding deformation, ensure the quality of the trunnion blocks, ensure that the sizes of the trunnion blocks and the tolerances of the surfaces of trunnions after final welding meet the relevant requirements on drawings, solve the problems of long production period and high manufacturing cost of the converter trunnion rings caused by the traditional process at present, meet the market requirements and improve the product competitiveness of enterprises.
The technical scheme for solving the technical problems is as follows:
a converter trunnion ring trunnion block welding process comprises the process route of trunnion forging → fine machining → welding, wherein after a forging workshop, a trunnion is transferred to a machining workshop from the forging workshop for final machining, the requirement of tolerance on trunnion block drawing paper is directly met, after protection is performed, the trunnion is transferred to a welding workshop, the welding workshop firstly assembles and welds a trunnion and inner and outer side plates, then assembles and welds a cover plate and a box inner rib plate, finally anneals, finally performs integral trial assembly, and can be completed after two times of transfer;
the relevant steps in the welding and annealing process are:
a. when the inner side plate and the outer side plate of the trunnion block are molded, the dimensional tolerance and the flatness need to be paid attention, and the trunnion block cannot be distorted;
b. preheating temperatures of an inner side plate, an outer side plate and a trunnion of the trunnion block before welding must be strictly controlled within the range of 150 ℃ and 200 ℃, and the temperature of a workpiece is monitored in the whole welding process to prevent cold cracks;
c. when the inner side plate and the outer side plate of the trunnion block are welded with the trunnion, the welding is carried out strictly according to the process requirements, and the welding needs to be turned over for multiple times to control the welding deformation;
d. annealing by adopting a crawler heater after welding, adopting a heating tool and making heat preservation measures;
e. the heat preservation measures in the whole production process need to be strictly controlled;
f. and after the annealing is finished, carrying out flaw detection according to the requirements of a drawing.
In the welding process of the trunnion block of the converter trunnion ring, the welding and turning method in the step c is as follows:
firstly, welding an upper welding seam of an inner side plate, welding half of the depth of a groove, about 20mm, and then turning 180 degrees by two welders in a symmetrical welding mode;
secondly, welding the lower welding seam of the outer side plate, namely simultaneously and symmetrically welding by two welders, fully welding the lower welding seam of the outer side plate, turning the lower welding seam by 180 degrees again, and continuously heating the lower welding seam of the inner side plate by using a heating pipe during welding;
thirdly, welding the upper welding seam of the inner side plate, symmetrically welding and fully welding the upper welding seam of the outer side plate by two welders at the same time, then performing gouging on the upper welding seam of the outer side plate, and continuously heating the upper welding seam of the outer side plate by using a heating pipe during welding;
fourthly, after gouging back, two welders symmetrically weld the upper welding seam of the outer side plate at the same time, fully weld, turn over 180 degrees again, while welding, heat the upper welding seam of the inner side plate continuously with the heating pipe;
fifthly, after turning over, firstly, carrying out gouging back chipping on a lower welding seam of the inner side plate, then, simultaneously and symmetrically welding an upper welding seam of the outer side plate by two welders, and when welding, continuously heating the upper welding seam of the outer side plate by using a heating pipe;
in the welding process, a riveter needs to monitor the perpendicularity of the trunnion by using infrared equipment, and the riveter informs the welder of adjusting the welding position when finding that the perpendicularity deformation exceeds 2mm, and adjusts the perpendicularity.
The invention has the beneficial effects that:
the trunnion block is manufactured according to the process, the manufacturing period can be saved by 35 days, and the processing cost can be saved by about 8 ten thousand yuan.
The invention is the pioneer of the manufacturing process of the trunnion block of the converter trunnion ring, breaks through the traditional process flow, adopts a unique welding method, effectively reduces the welding stress and controls the welding deformation, ensures the welding quality of the two trunnion blocks, and can finish the annealing after welding without entering an annealing furnace. The welding process can solve the problems of long production period and high manufacturing cost of the converter backing ring caused by the traditional process, meets the market requirement and improves the product competitiveness of enterprises.
Drawings
FIG. 1 is a schematic view of a trunnion welded inboard and outboard plates of the present invention.
The figures are labeled as follows: the welding device comprises an upper welding seam 1 of an inner side plate, a lower welding seam 2 of an outer side plate, an upper welding seam 3 of the outer side plate, a lower welding seam 4 of the inner side plate, a trunnion 5, an inner side plate 6 and an outer side plate 7.
Detailed Description
The welding process has the main effects that the final precision guarantee of the trunnion block is changed from post-welding processing to welding process control, and the aim of guaranteeing the product quality is achieved by adopting measures of adjusting the welding position, the welding sequence and the like in the welding process. Compared with the process route of trunnion forging → rough machining → welding → annealing → fine machining → welding trial assembly in the traditional process, the three times of transportation are reduced, thereby greatly reducing the production period and the manufacturing cost.
The trunnion block is formed by welding a trunnion 5, an inner side plate 6 and an outer side plate 7, beveling is performed on the joint of the trunnion 5, the inner side plate 6 and the outer side plate 7 before welding, and V-shaped bevels are respectively arranged on two sides of the joint of the trunnion 5 and the plate surfaces of the inner side plate 6 and the outer side plate 7.
The trunnion 5 of the present invention is finished before welding the inner plate 6 and the outer plate 7, and the following matters are noted before welding:
firstly, the surface of the trunnion 5 needs to be protected by a calcium plastic plate after finish machining, so that the surface is prevented from being scratched and gouged.
Secondly, the groove size is required to meet the drawing tolerance during machining of the trunnion 5, so that assembly cannot be carried out.
The relevant steps of the invention in the welding and annealing process of the trunnion 5, the inner side plate 6 and the outer side plate 7 are as follows:
a. when the inner plate 6 and the outer plate 7 are curved, dimensional tolerance and flatness are required, and no distortion occurs.
b. The preheating temperature of the inner side plate 6, the outer side plate 7 and the trunnion 5 before welding must be strictly controlled within the range of 150-200 ℃, and the temperature of the workpiece is monitored in the whole welding process to prevent cold cracks.
c. When an inner side plate (6), an outer side plate (7) and a trunnion (5) of the trunnion block are welded, the welding is executed according to strict requirements of process steps in the lower welding and overturning process, and the welding deformation is controlled by overturning for 3-5 times;
d. and (4) annealing by adopting a crawler heater after welding, and adopting a heating tool and well taking heat preservation measures.
e. The heat preservation measures in the whole production process need to be strictly controlled.
f. And after the annealing is finished, carrying out flaw detection according to the requirements of a drawing.
The welding turnover method in the step c is as follows:
firstly, welding an upper welding seam 1 of an inner side plate, welding half of the depth of a groove, about 20mm, and then turning 180 degrees by two welders in a symmetrical welding mode;
secondly, welding a lower welding seam 2 of the outer side plate, namely simultaneously and symmetrically welding by two welders, fully welding the lower welding seam 2 of the outer side plate, turning the outer side plate for 180 degrees again, and continuously heating the lower welding seam 4 of the inner side plate by using a heating pipe during welding;
thirdly, welding an upper welding seam 1 of the inner side plate, symmetrically welding and fully welding the upper welding seam 3 of the outer side plate by two welders at the same time, and then performing gouging on the upper welding seam 3 of the outer side plate by using a heating pipe during welding;
fourthly, after gouging back, two welders symmetrically weld the upper welding seam 3 of the outer side plate at the same time, fully weld, turn over 180 degrees again, while welding, heat the upper welding seam 1 of the inner side plate continuously with the heating pipe;
fifthly, after turning, firstly carrying out gouging back chipping on a lower welding seam 4 of the inner side plate, then simultaneously and symmetrically welding an upper welding seam 3 of the outer side plate by two welders, and fully welding, wherein during welding, the upper welding seam 3 of the outer side plate is continuously heated by a heating pipe;
in the welding process, the riveter needs to monitor the perpendicularity of the trunnion 5 by using infrared equipment, and the riveter informs the welder of adjusting the welding position when finding that the perpendicularity deformation exceeds 2mm, and adjusts the perpendicularity.
The invention meets the requirements of the drawing and the technical protocol of welding:
firstly, after the groove machining is finished, MT flaw detection is carried out in a 40mm area around the groove, the execution standard JB4730.4-2005 is checked, and the grade I is qualified.
Secondly, preheating before welding at 150-.
Thirdly, performing MT flaw detection on the welding seam and the areas of 40mm on two sides after welding, and checking execution standard JB4730.4-2005, wherein the grade I is qualified.
Fourthly, performing 100% UT flaw detection after welding, executing JB/T4730.3-2005 standard, detecting grade B, and judging whether the quality evaluation grade of the welding seam is not lower than grade I.
The invention solves the problems of long construction period and high cost of processing the trunnion ring. The new process route is trunnion forging → processing (tempering) → welding (annealing), and the annealing adopts a track heater and a heating pipe. The new technical scheme completely changes the process method of the traditional process, the trunnion of the trunnion ring is directly subjected to finish machining, and the workpiece finally meets the drawing requirements and meets the requirements of customers by controlling the welding sequence and the welding process according to the characteristics of the detailed structure of the trunnion block. Meanwhile, the process can save 25-45 days of production period (related to the size of the product), and can save the processing cost by about 5-10 ten thousand yuan (related to the size of the product), thereby greatly improving the converter market competitiveness of enterprises.
Claims (2)
1. A converter trunnion ring trunnion block welding process is characterized in that: the method adopts the process route of trunnion forging → fine machining → welding, after the trunnion is in a forging shop, the forging shop transfers the trunnion to a processing shop for final processing, the requirement of tolerance on trunnion block drawing paper is directly met, after protection is done, the trunnion is transferred to a welding shop, the welding shop firstly assembles and welds the trunnion and inner and outer side plates, then assembles and welds the cover plate and the inner rib plate of the box body, finally anneals, finally carries out integral trial assembly, and finishes the process after two times of transferring;
the specific steps in the welding and annealing process are as follows:
a. when the inner side plate (6) and the outer side plate (7) of the trunnion block are bent, the dimensional tolerance and the flatness are required to be paid attention, and the trunnion block cannot be twisted;
b. preheating temperature of the trunnion block before welding the inner side plate (6), the outer side plate (7) and the trunnion (5) must be strictly controlled within the range of 150-;
c. when an inner side plate (6), an outer side plate (7) and a trunnion (5) of the trunnion block are welded, the welding is executed according to strict requirements of process steps in the lower welding and overturning process, and the welding deformation is controlled by overturning for 3-5 times;
d. annealing by adopting a crawler heater after welding, adopting a heating tool and making heat preservation measures;
e. the heat preservation measures in the whole production process need to be strictly controlled;
f. and after the annealing is finished, carrying out flaw detection according to the requirements of a drawing.
2. The process of welding the trunnion block of the converter trunnion ring according to claim 1, wherein: the welding turning method in the step c is as follows:
firstly, welding an upper welding seam (1) of an inner side plate, welding half of the depth of a groove by two welders in a symmetrical welding mode (about 20mm is shown (please give a range), and then turning for 90-180 degrees;
secondly, welding a lower welding seam (2) of the outer side plate, namely simultaneously and symmetrically welding by two welders, fully welding the lower welding seam (2) of the outer side plate, turning the lower welding seam for 90-180 degrees again, and continuously heating the lower welding seam (4) of the inner side plate by using a heating pipe during welding;
thirdly, welding an upper welding seam (1) of the inner side plate, symmetrically welding and fully welding the upper welding seam (3) of the outer side plate at the same time by two welders, gouging and back chipping the upper welding seam (3) of the outer side plate, and continuously heating the upper welding seam (3) of the outer side plate by a heating pipe during welding;
fourthly, after gouging back, two welders symmetrically weld the upper welding seam (3) of the outer side plate at the same time, fully weld, turn over 90-180 degrees again, while welding, heat the upper welding seam (1) of the inner side plate continuously with the heating pipe;
fifthly, after turning, firstly carrying out gouging back chipping on a lower welding seam (4) of the inner side plate, then simultaneously and symmetrically welding an upper welding seam (3) of the outer side plate by two welders, and continuously heating the upper welding seam (3) of the outer side plate by using a heating pipe during welding;
in the welding process, the riveting worker needs to monitor the verticality of the trunnion (5) by using infrared equipment, and informs the welding worker to adjust the welding position when discovering that the verticality deformation exceeds 2mm, so as to adjust the verticality.
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| CN202010201402.3A CN111331323B (en) | 2020-03-20 | 2020-03-20 | Welding process for trunnion block of converter backing ring |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112981037A (en) * | 2021-02-05 | 2021-06-18 | 安徽马钢设备检修有限公司 | Fixed assembly welding structure and welding process for lug seat of converter trunnion ring body |
| CN114273761A (en) * | 2021-12-31 | 2022-04-05 | 辽宁顺达机械制造(集团)有限公司 | Converter trunnion ring integrated welding method |
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| CN111331323B (en) | 2022-01-28 |
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