CN108544055B - Full-automatic surfacing method for 58% nickel-based alloy in groove of combustion chamber of cylinder cover - Google Patents
Full-automatic surfacing method for 58% nickel-based alloy in groove of combustion chamber of cylinder cover Download PDFInfo
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- CN108544055B CN108544055B CN201810334061.XA CN201810334061A CN108544055B CN 108544055 B CN108544055 B CN 108544055B CN 201810334061 A CN201810334061 A CN 201810334061A CN 108544055 B CN108544055 B CN 108544055B
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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
- B23K9/00—Arc welding or cutting
- B23K9/04—Welding for other purposes than joining, e.g. built-up welding
- B23K9/042—Built-up welding on planar surfaces
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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
- B23K9/00—Arc welding or cutting
- B23K9/0026—Arc welding or cutting specially adapted for particular articles or work
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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
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
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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
- B23K9/00—Arc welding or cutting
- B23K9/235—Preliminary treatment
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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
- B23K9/00—Arc welding or cutting
- B23K9/24—Features related to electrodes
- B23K9/28—Supporting devices for electrodes
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Abstract
The utility model provides a full-automatic build-up welding method that is used for 58% nickel base alloy in cylinder head combustion chamber recess, includes full-automatic build-up welding system, and this full-automatic build-up welding system includes positioner and welding robot, its characterized in that: the full-automatic surfacing method comprises the following steps: a) processing a groove in a combustion chamber of a cylinder cover; b) the welding area in the groove is always in a horizontal position through the linkage of the positioner and the welding robot; c) welding is carried out in a swinging mode in the groove according to a snake-shaped welding path track by adopting a welding robot, and no stay is carried out in each welding path; d) by using a molten drop short circuit transition welding mode, the output current of a power supply is close to zero, the thickness of a single layer of a surfacing layer reaches 4mm, and the iron content in a surfacing area of the cylinder cover is ensured to be less than 5%. The invention achieves the purposes of reducing cost, improving work efficiency, reducing labor intensity and ensuring product quality, and is particularly suitable for full-automatic surfacing operation of 58% nickel-based alloy in the cylinder cover combustion chamber groove with the surfacing layer height of 4mm and the requirement of surfacing area iron element content of less than 5%.
Description
Technical Field
The invention relates to welding processing of large diesel engine parts, in particular to a full-automatic surfacing method for 58% nickel-based alloy in a groove of a combustion chamber of a cylinder cover, and belongs to the technical field of welding processes.
Background
The cylinder cover is one of important parts of a high-power low-speed marine diesel engine. Referring to fig. 1 and 2, there is shown a schematic structural diagram of a cylinder head of a large marine diesel engine, which weighs about 5.5 tons, the diameter of an exhaust valve seat hole 2 is 638mm, the diameter of a combustion chamber hole 1 is 901mm, grooves 3 are uniformly distributed in the combustion chamber hole 1, and a mounting hole 4 and a side surface 5 on a large outer circle are processed before welding. Usually, a cylinder cover of a large diesel engine adopts 58% nickel-based alloy which is welded in a groove 3 of a combustion chamber in a surfacing mode for strengthening treatment so as to bear the impact of high temperature and high pressure and achieve the purpose of prolonging the service life.
At present, the domestic adopted 58 percent nickel-based alloy surfacing modes are manual surfacing and semi-automatic surfacing respectively. The manual surfacing has the problems of high labor intensity, poor working environment, poor process performance, low parameter curing rate, unstable quality, low surfacing efficiency, serious dependence on welders and the like. The semi-automatic surfacing welding adopts a rotary worktable and a numerical control welding machine, wherein the rotary worktable has two functions of swinging and rotating, and is positioned by adopting a modularized and standardized tool fixture, a workpiece is installed on the rotary worktable to actively rotate and swing, a numerical control program control system moves a workpiece groove into a surfacing welding area, all surfacing welding parameters can be preset in advance, and then the rotary worktable rotates the angle, moves the cross arm longitudinally in the front and back direction and manually adjusts the welding process to complete the surfacing welding.
The efficiency of semi-automatic surfacing is more than 4 times that of manual surfacing, but still has the problem of unstable surfacing quality, and usually, the defect is concentrated in the side wall of the groove 3. The reason for this is that the welding gun cannot be adjusted and continuously welded in the existing semi-automatic welding process, so that multiple arc striking and arc stopping are caused at the side wall of the groove 3; the depth drop of the arc striking and arc closing positions is large, and the welding current fluctuation is large due to the fact that the dry elongation of the welding wire is inconsistent; in addition, the 58 percent nickel-based alloy has viscous molten pool, poor fluidity, large surface tension of molten drops, difficult spreading, easy generation of defects of unfused, air holes, hot cracks and the like in the surfacing process; when the height of a surfacing layer is 4-5 mm and the iron content of a surfacing area is required to be less than 5%, the number of the surfacing layers is more than or equal to 2, so that more expensive welding materials are consumed, and more surfacing working hours are increased.
Disclosure of Invention
The invention aims to provide a full-automatic surfacing method for 58% of nickel-based alloy in a groove of a combustion chamber of a cylinder cover, which adopts a full-automatic surfacing system and scientific and reasonable process parameters to achieve the purposes of reducing cost, improving work efficiency, reducing labor intensity and ensuring product quality.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the utility model provides a full-automatic build-up welding method that is used for 58% nickel base alloy in cylinder head combustion chamber recess, includes full-automatic build-up welding system, and this full-automatic build-up welding system includes positioner and welding robot, its characterized in that: the full-automatic surfacing method comprises the following steps:
a) processing a groove in a combustion chamber of a cylinder cover;
b) the welding area in the groove is always in a horizontal position through the linkage of the positioner and the welding robot;
c) welding is carried out in a swinging mode in the groove according to a snake-shaped welding path track by adopting a welding robot, and no stay is carried out in each welding path;
d) by using a molten drop short circuit transition welding mode, the output current of a power supply is close to zero, the thickness of a single layer of a surfacing layer reaches 4-5 mm, and the iron content in a surfacing area of the cylinder cover is ensured to be less than 5%.
Further, in the step a), the depth of the processed groove is 3.5mm, a groove is processed on the periphery of the groove, and the angle range of the groove is 15-20 degrees.
Further, in the step c), the snake-shaped welding bead track is formed by connecting a plurality of linear welding beads and corner welding beads end to end, when the linear welding beads are welded, the welding current is 225-245A, the welding voltage is 16-20V, and the welding speed is 210-280 mm/min; when the corner welding bead is welded, the welding current is 135-150A, the welding voltage is 12-14V, and the welding speed is 400-450 mm/min.
Further, in the step c), a mixed gas of 97.5% of argon and 2.5% of carbon dioxide is used as a protective gas during welding, and the flow rate of the protective gas is 21-22L/min.
Further, in said step d), the welding arc point is kept away from the workpiece to be treated to limit the diffusion of workpiece temperature and workpiece components in the gas protection layer.
Further, in the step d), the number of the surfacing layers is one.
Compared with the prior art, the invention has the following remarkable advantages:
1. because each welding seam is fully penetrated, each welding bead is proper in thickness, and has no damage and mechanical property, the quality detection meets the relevant requirements, and the purpose of improving the welding quality is achieved.
2. Due to the use of the single-layer welding seam, the use amount of expensive welding materials can be reduced, and the production cost is greatly reduced.
The method is particularly suitable for surfacing of 58% nickel-based alloy of the cylinder cover groove with a surfacing layer height of 4-5 mm and a surfacing area with iron element content less than 5%.
Drawings
Fig. 1 is a schematic view of a cylinder head.
Fig. 2 is a top view of fig. 1.
FIG. 3 is a schematic view of the full-automatic bead welding system of the present invention.
FIG. 4 is a schematic diagram of a groove side groove pattern.
FIG. 5 is a schematic diagram of the welding trajectory of the welding gun according to the present invention.
In the figure:
1-combustion chamber hole, 2-exhaust valve seat hole, 3-groove, 4-mounting hole, 5-side face, 6-positioner, 7-trolley, 8-welding power supply, 9-welding robot, 10-welding gun, 11-cylinder cover, A-linear welding bead and B-corner welding bead.
Detailed Description
The invention will be described in more detail with reference to the following figures and examples, which should not be construed as limiting the invention thereto
The scope of protection of the invention.
The full-automatic surfacing method is used for surfacing 58% nickel-based alloy in the groove of the combustion chamber of the cylinder cover. Referring to fig. 2, the grooves 3 are distributed on the inner wall of the cylinder head combustion chamber hole 1 and are formed by 3 sector-shaped curved surfaces.
The full-automatic surfacing method is realized on a full-automatic surfacing system, the structure of the full-automatic surfacing system is shown in figure 3, the full-automatic surfacing system comprises a positioner 6 and a welding robot 9 installed on a trolley 7, and a welding gun 10 is arranged at the front end of the welding robot 9 and is connected with a welding power supply 8.
The following is an embodiment of the present invention.
The full-automatic surfacing method comprises the following steps:
a) a recess 3 is machined in the combustion chamber of the cylinder head 11.
Firstly, milling three grooves 3 of a combustion chamber of an air cylinder cover 11 on a numerical control machine tool, wherein the depth of each groove is 3.5mm, and a groove is machined on the periphery of each groove, wherein the angle of the groove is 16 degrees, as shown in figure 4.
Secondly, the surfacing area of the cylinder cover is cleaned, and oil stain, grease and the like are removed by using a cleaning agent.
And then, putting the workpiece into a trolley type resistance furnace to be heated integrally, and ensuring that the temperature before welding is 150-180 ℃.
b) And the welding area in the groove 3 is always in a horizontal position through the linkage of the positioner 6 and the welding robot 9.
Referring to fig. 3, the heated cylinder head 11 is hoisted on a two-axis positioner 6 of a full-automatic surfacing system, and after clamping, a swinging mechanism and a steering mechanism are started to adjust the position of the groove 3 to a horizontal position; and moving the trolley 7 to enable the welding gun 10 to reach a preset position, and enabling the welding area to be in a horizontal position all the time through linkage of the positioner 6 and the welding robot 9.
c) The welding robot 9 is used to perform the swing welding in the groove 3 according to the 'snake' welding path track without stopping in each welding path.
The welding wire used for welding was Inconel625 with a diameter of 1.2mm and the chemical composition is given in Table 1 below:
TABLE 1 (Unit:% by mass)
| C | Mn | P | S | Fe | Si | Cu | Ni | Al | Ti | Cr | Nb+Ta | Mo |
| 0.01 | 0.01 | 0.004 | 0.001 | 0.26 | 0.07 | 0.02 | 58 | 0.15 | 0.21 | 22.55 | 3.59 | 8.90 |
And then, during welding, the dry elongation of the welding wire is kept between 17 mm and 18mm, the welding wire is positioned at the center position of each welding pass, and referring to fig. 5, the starting point and the ending point are positioned at the outer sides of the grooves 3 by 3mm to 5 mm. When the welding robot 9 is in bead welding of the side wall of the groove, in order to obtain the optimum technological attitude of the side wall transition in the continuous welding state, the attitude of the welding gun 10 is adjusted, then the welding is performed by swinging the snake-shaped track in the welding bead of the groove 3, and the stopping is not performed in each welding bead, the snake-shaped track is formed by connecting a plurality of straight welding beads A and corner welding beads B end to end, the welding of the straight welding beads A and the corner welding beads B adopts different technological parameters, and the concrete welding technological parameters are as follows in table 2:
TABLE 2
| Trace of build-up welding | Electric current | Voltage of | Amplitude of oscillation | Track spacing | Wire feed speed | Speed of welding |
| Straight bead A | 225～ |
16～20V | 14mm | 11mm | 12.1m/min | 210～280mm/min |
| Corner bead B | 135～150A | 12～14V | 14mm | 11mm | 12.1m/min | 400～450mm/min |
During welding, mixed gas of 97.5% argon and 2.5% carbon dioxide is distributed as protective gas, and the gas flow is 21-22L/min. Because carbon dioxide is a surface active element, a small amount of carbon dioxide is added into argon, the surface tension of liquid metal can be reduced, the flow of the nickel-based alloy is promoted, and the problems of irregular weld joint forming, undercut, incomplete fusion and the like can be avoided even if the thickness of a single layer reaches 4 mm.
d) And a molten drop short circuit transition welding mode is adopted, and the thickness of a single layer of the surfacing layer reaches 4 mm.
The welding mode adopts molten drop short circuit transition, the number of overlaying layers is one, the thickness of a single layer reaches 4mm, and the iron element content in an overlaying area of the cylinder cover is ensured to be less than 5%. After the welding mode uses the molten drop short circuit transition, the output current of the power supply is almost zero, the electric arc action point is not directly positioned on the workpiece to be processed, namely the welding electric arc action point avoids the workpiece to be processed, and the temperature of the workpiece and the diffusion of the components of the workpiece in the gas protection layer can be limited. The starting time of arc generation is set in a welding control system, welding current is automatically reduced until the arc is extinguished, and medium-pulse type welding wire conveying is adjusted, so that the pulse type welding wire conveying effectively improves the transition of welding wire molten drops, can effectively overcome gravity, and can improve deposition efficiency while spreading to the two sides and depth of a groove.
After welding, the cylinder head 11 is wrapped with aluminum silicate heat-insulating cotton to perform heat-insulating treatment on the whole body, and the heat-insulating time is more than 36 hours.
Then, turning the overlaying layer on the groove 3 of the combustion chamber hole 1 on the cylinder cover 11 on a machine tool, and finally ensuring that the thickness of the 58% nickel-based alloy overlaying layer is 3 mm.
And finally, inspecting a 58% nickel-based alloy surfacing area, wherein visual inspection, ultrasonic wave and dye penetrant inspection are combined for inspection, and if the defects exceeding the quality standard are found, the defects are repaired by manual grinding by a fitter and a manual argon arc welding repair welding method.
While the present invention has been described in further detail with reference to specific preferred embodiments, it is not intended that the present invention be limited to the specific embodiments described above. For those skilled in the art, without departing from the spirit of the invention, several simple deductions or equivalent substitutions can be made, which shall be considered to belong to the protection scope of the invention.
Claims (6)
1. The utility model provides a full-automatic build-up welding method that is used for 58% nickel base alloy in cylinder head combustion chamber recess, uses full-automatic build-up welding system, and this full-automatic build-up welding system includes positioner and welding robot, its characterized in that: the full-automatic surfacing method comprises the following steps:
a) processing a groove in a combustion chamber of a cylinder cover;
b) the welding area in the groove is always in a horizontal position through the linkage of the positioner and the welding robot;
c) performing swing welding in the groove according to a snake-shaped welding path track by using a welding robot, wherein the welding robot does not stop in each welding path, and the starting point and the end point are positioned at the outer side of the groove by 3-5 mm;
d) by using a molten drop short circuit transition welding mode, the output current of a power supply is close to zero, the thickness of a single layer of a surfacing layer reaches 4-5 mm, and the iron content in a surfacing area of the cylinder cover is ensured to be less than 5%.
2. The method of full-automatic weld deposit of 58% nickel-base alloy in cylinder head combustion chamber recess according to claim 1, characterized in that: in the step a), the depth of the processed groove is 3.5mm, a groove is processed on the periphery of the groove, and the angle range of the groove is 15-20 degrees.
3. The method of full-automatic weld deposit of 58% nickel-base alloy in cylinder head combustion chamber recess according to claim 1, characterized in that: in the step c), the snake-shaped welding bead track is formed by connecting a plurality of linear welding beads and corner welding beads end to end, when the linear welding beads are welded, the welding current is 225-245A, the welding voltage is 16-20V, and the welding speed is 210-280 mm/min; when the corner welding bead is welded, the welding current is 135-150A, the welding voltage is 12-14V, and the welding speed is 400-450 mm/min.
4. The method of full-automatic weld deposit of 58% nickel-base alloy in cylinder head combustion chamber recess according to claim 1, characterized in that: in the step c), a mixed gas of 97.5% of argon and 2.5% of carbon dioxide is used as a protective gas during welding, and the flow rate of the protective gas is 21-22L/min.
5. The method of full-automatic weld deposit of 58% nickel-base alloy in cylinder head combustion chamber recess according to claim 1, characterized in that: in said step d), the welding arc point is kept away from the workpiece to be treated in order to limit the diffusion of workpiece temperature and workpiece components in the gas protection layer.
6. The method of full-automatic weld deposit of 58% nickel-base alloy in cylinder head combustion chamber recess according to claim 1, characterized in that: in the step d), the number of the surfacing layers is one.
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| CN110125515B (en) * | 2019-04-24 | 2021-11-16 | 武汉船用机械有限责任公司 | Nickel alloy surfacing method |
| CN110216360B (en) * | 2019-05-13 | 2022-03-15 | 上海船舶工艺研究所(中国船舶工业集团公司第十一研究所) | Nickel-based alloy surfacing welding process for alloy tank |
| CN110434425B (en) * | 2019-07-01 | 2022-06-03 | 宜昌船舶柴油机有限公司 | Surfacing welding method for fuel injection area of cylinder head of S60MC diesel engine |
| CN111822818B (en) * | 2020-07-21 | 2022-09-13 | 福尼斯(南京)表面工程技术有限公司 | Method for automatically surfacing reducing pipe by using novel surfacing equipment |
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| US9085043B2 (en) * | 2009-07-16 | 2015-07-21 | Lincoln Global, Inc. | Submerged arc welding system with pressurized flux delivery and welding torch |
| KR100949062B1 (en) * | 2009-08-18 | 2010-03-25 | 에스피하이테크 주식회사 | Plasma automatic hardfacing welding machine for butterfly valve |
| CN101885100A (en) * | 2010-07-28 | 2010-11-17 | 上海中船三井造船柴油机有限公司 | Nickel-chromium-molybdenum alloy automatic surfacing technology for diesel engine cylinder head for ship |
| CN202900344U (en) * | 2012-10-25 | 2013-04-24 | 沈阳航天三菱汽车发动机制造有限公司 | Valve structure of gas-fueled vehicles engine cylinder cover |
| JP5858007B2 (en) * | 2013-07-01 | 2016-02-10 | トヨタ自動車株式会社 | Overlaying method for valve seat and manufacturing method of cylinder head |
| CN106112204A (en) * | 2016-07-15 | 2016-11-16 | 南京国际船舶设备配件有限公司 | A kind of marine low-speed machine air valve sealing surface build-up welding Nickel-based Alloy Welding technique |
| CN106041531B (en) * | 2016-07-26 | 2019-01-11 | 南京国际船舶设备配件有限公司 | A kind of marine low-speed machine air valve welding robot workstation |
| CN106444638B (en) * | 2016-07-26 | 2018-12-04 | 南京国际船舶设备配件有限公司 | A kind of marine low-speed machine air valve welding robot workstation control system |
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