CN115401428A - Nodular cast iron traction motor welding process for rail transit - Google Patents
Nodular cast iron traction motor welding process for rail transit Download PDFInfo
- Publication number
- CN115401428A CN115401428A CN202211250832.XA CN202211250832A CN115401428A CN 115401428 A CN115401428 A CN 115401428A CN 202211250832 A CN202211250832 A CN 202211250832A CN 115401428 A CN115401428 A CN 115401428A
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- Prior art keywords
- welding
- cast iron
- rail transit
- traction motor
- junction box
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- 238000003466 welding Methods 0.000 title claims abstract description 128
- 238000000034 method Methods 0.000 title claims abstract description 29
- 230000008569 process Effects 0.000 title claims abstract description 28
- 229910001141 Ductile iron Inorganic materials 0.000 title claims abstract description 17
- 239000000463 material Substances 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- UGKDIUIOSMUOAW-UHFFFAOYSA-N iron nickel Chemical compound [Fe].[Ni] UGKDIUIOSMUOAW-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims abstract description 5
- 239000010935 stainless steel Substances 0.000 claims abstract description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 4
- 238000004140 cleaning Methods 0.000 claims abstract description 4
- 238000002474 experimental method Methods 0.000 claims abstract description 4
- 230000008676 import Effects 0.000 claims abstract description 4
- 229910000863 Ferronickel Inorganic materials 0.000 claims abstract 2
- 238000005496 tempering Methods 0.000 claims description 9
- 238000005336 cracking Methods 0.000 claims description 6
- 238000006356 dehydrogenation reaction Methods 0.000 claims description 6
- 238000005498 polishing Methods 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 6
- 230000035882 stress Effects 0.000 claims description 6
- 230000008439 repair process Effects 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 3
- 230000032683 aging Effects 0.000 claims description 3
- 239000010953 base metal Substances 0.000 claims description 3
- 230000008859 change Effects 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 239000013078 crystal Substances 0.000 claims description 3
- 230000007547 defect Effects 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims description 3
- 239000012530 fluid Substances 0.000 claims description 3
- 238000005242 forging Methods 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 238000013021 overheating Methods 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 230000035515 penetration Effects 0.000 claims description 3
- 238000005488 sandblasting Methods 0.000 claims description 3
- 238000010583 slow cooling Methods 0.000 claims description 3
- 239000007790 solid phase Substances 0.000 claims description 3
- 238000007711 solidification Methods 0.000 claims description 3
- 230000008023 solidification Effects 0.000 claims description 3
- 238000005493 welding type Methods 0.000 claims description 3
- 229910000831 Steel Inorganic materials 0.000 claims description 2
- 238000000465 moulding Methods 0.000 claims description 2
- 239000010959 steel Substances 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 3
- 238000007689 inspection Methods 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- 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
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Power Engineering (AREA)
- Mechanical Engineering (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
Abstract
The invention discloses a welding process of a nodular cast iron traction motor for rail transit, which comprises the following steps: 1) Cleaning stainless steel at the position of the junction box welded on the traction machine shell by using alcohol before welding; 2) The air conditioner and the heating device are used for temperature control in the welding room; 3) Preheating a ferronickel welding rod in a heating furnace to 180 ℃; measuring by using a contact type temperature measuring instrument; 4) Preheating flame at the position of the traction machine shell for welding the junction box to 180 ℃; measuring by using a contact type temperature measuring instrument; 5) Fixing the junction box on a traction case by using screws and then welding, wherein the welding needs to use Isa import nickel iron welding rod OK92.58 through repeated experiments; the material has better matching property with two parent materials; the length of the riveting spot is 3 cm; according to the welding process of the nodular cast iron traction motor for rail transit, provided by the invention, through early treatment, middle-stage special process and later-stage special inspection and treatment, cracks can be well avoided in welding seams, a good welding effect is achieved, and the welding process has remarkable progress.
Description
Technical Field
The invention relates to the technical field of welding, in particular to a welding process of a nodular cast iron traction motor for rail transit.
Background
The high-speed rail traction motor is characterized in that a motor shell is made of TQ500-7 nodular cast iron, a motor junction box connecting plate is made of SUS304 stainless steel, two different materials are welded by different materials, the welding process belongs to a special welding process, the two materials are different in material characteristics such as yield strength, elongation and tensile strength, a common welding process cannot complete welding, and long weld cracks exist, so that the problem needs to be solved by the nodular cast iron traction motor welding process for rail transit.
Disclosure of Invention
The invention aims to provide a welding process of a ductile cast iron traction motor for rail transit, which aims to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a nodular cast iron traction motor welding process for rail transit comprises the following steps:
1) Cleaning stainless steel at the position of the junction box welded on the tractor shell by using alcohol before welding;
2) The air conditioner and the heating device are used for temperature control in the welding room;
3) Preheating a nickel-iron welding rod in a heating furnace to 180 ℃; measuring by using a contact type temperature measuring instrument;
4) Preheating flame at the position of the traction machine shell for welding the junction box to 180 ℃; measuring by using a contact type temperature measuring instrument;
5) Fixing the junction box on a traction case by using screws and then welding, wherein the welding needs to use Isa import nickel iron welding rod OK92.58 through repeated experiments; the material has better matching property with two parent materials; the length of the riveting spot is 3 cm;
6) Polishing the welding seam with the height of 2/3 of the rivet welding seam after welding; the forming of appearance welding seams is facilitated;
7) After polishing, measuring the temperature of a welding position and the temperature of a base metal, wherein the temperature cannot be lower than 180 ℃; measuring by using a contact type temperature measuring instrument;
8) Formal welding, wherein a welding rod with a welding angle A4 and a diameter of 2.5 can only be used for 1/3 of the length, and the welding rod is burnt due to overheating, so that the welding type is reduced; controlling the length of a welding seam;
9) The arc welding is stopped, and the arc crater must be filled to prevent the arc crater from cracking; after welding one section, immediately knocking the steel bar by using a welding seam knocking air hammer, wherein the end part of the knocking hammer is required to be hemispherical, knocking the semi-molten welding seam to be equal to secondary forging, so that stress can be removed, and a solidification crystalline structure and a solid phase change structure can be improved; the toughness and the fatigue resistance of the welding seam are improved, so that the risk of cracking of the welding seam is eliminated;
10 Heat welding and heat affected zone with flame after knocking is completed, the temperature is more than or equal to 300 ℃; the quick dehydrogenation treatment is realized; preventing the generation of hydrogen induced cracks;
11 Carrying out heat preservation treatment immediately after dehydrogenation treatment, and carrying out heat preservation and slow cooling by using an industrial heat blanket until welding is finished;
12 Putting the shell into a tempering furnace for tempering treatment, and naturally cooling the furnace body with the temperature of the furnace to be below 100 ℃ for opening the furnace after the tempering treatment is finished;
13 The shell is subjected to aging vibration after being taken out of the furnace, so that stress is eliminated, crystal grains are refined, and the strength is improved;
14 Sand blasting treatment after discharging to remove surface impurities;
15 PT penetration detection is carried out on the welding position of the machine shell; defects are found and welding repair is carried out, preheating is needed before repair, positions where PT penetrating fluid leaks must be ground off, and then welding is carried out.
Preferably, in the step 2), the temperature is controlled to be more than 15 ℃, and the humidity is less than or equal to 30%.
Preferably, in the step 8), the length of the weldable welding seam is 2.5-3 cm.
Preferably, in the step 15), the welding is repaired, and the welding process repeats the steps 1 to 15.
Preferably, the parent metal is a traction machine shell and a junction box.
Has the advantages that: the beneficial effects of the invention are: according to the welding process of the ductile cast iron traction motor for rail transit, cracks can be well avoided during welding through early treatment, middle-stage special process and later-stage special inspection and treatment, a good welding effect is achieved, and the welding process has remarkable progress.
Detailed Description
The technical solution of the present patent will be described in further detail with reference to the following embodiments.
A nodular cast iron traction motor welding process for rail transit comprises the following steps:
1) Cleaning stainless steel at the position of the junction box welded on the traction machine shell by using alcohol before welding;
2) The air conditioner and the heating device are used for temperature control in the welding room;
3) Preheating a nickel-iron welding rod in a heating furnace to 180 ℃; measuring by using a contact type temperature measuring instrument;
4) Preheating flame at the position of the traction machine shell for welding the junction box to 180 ℃; measuring by using a contact type temperature measuring instrument;
5) Fixing the junction box on a traction case by using screws and then welding, wherein the welding needs to use Isa import nickel iron welding rod OK92.58 through repeated experiments; the material has better matching property with two parent materials; the length of the riveting spot is 3 cm;
6) Polishing the welding seam with the height of 2/3 of the rivet welding seam after welding; the molding of appearance welding seams is facilitated;
7) After polishing, measuring the temperature of a welding position and a base metal, wherein the temperature cannot be lower than 180 ℃; measuring by using a contact type temperature measuring instrument;
8) Formal welding, wherein a welding rod with the welding angle A4 and the diameter of 2.5 can only be used for 1/3 of the length, the welding rod is burnt due to overheating, and the welding type is reduced; controlling the length of a welding seam;
9) The arc welding is stopped, and the arc crater must be filled to prevent the arc crater from cracking; after a section is welded, immediately using a welding seam to knock an air hammer for quick knocking, wherein the end part of the knocking hammer is required to be hemispherical, knocking the welding seam in a semi-molten state is equal to secondary forging, so that the stress can be removed, and a solidification crystalline structure and a solid phase change structure can be improved; the toughness and the fatigue resistance of the welding seam are improved, so that the risk of cracking of the welding seam is eliminated;
10 Heat welding and heat affected zone with flame after knocking is finished, the temperature is more than or equal to 300 ℃; the quick dehydrogenation treatment is realized; preventing the generation of hydrogen induced cracks;
11 Performing heat preservation treatment immediately after the dehydrogenation treatment, and performing heat preservation and slow cooling by using an industrial heat blanket until the welding is finished;
12 Putting the shell into a tempering furnace for tempering treatment, and naturally cooling the furnace body with the temperature of the furnace to be below 100 ℃ for opening the furnace after the tempering treatment is finished;
13 The shell is subjected to aging vibration after being taken out of the furnace, so that stress is eliminated, crystal grains are refined, and the strength is improved;
14 Sand blasting treatment after discharging to remove surface impurities;
15 PT penetration detection is carried out on the welding position of the machine shell; defects are found to be repaired by welding, preheating is needed before repairing, the position where PT penetrating fluid leaks must be ground off, and then welding is carried out.
In the invention, in the step 2), the temperature is controlled to be more than 15 ℃, and the humidity is less than or equal to 30%.
In the invention, in the step 8), the length of the weldable weld joint is 2.5-3 cm.
In the invention, in the step 15), the welding is repaired, and the welding process repeats the steps 1-15.
In the invention, the parent metal is a traction machine shell and a junction box.
According to the welding process of the ductile cast iron traction motor for rail transit, cracks can be well avoided during welding through early treatment, middle-stage special process and later-stage special inspection and treatment, a good welding effect is achieved, and the welding process has remarkable progress.
The above embodiments are provided to further explain the objects, technical solutions and advantages of the present invention in detail, and it should be understood that the above embodiments are only examples of the present invention and should not be construed as limiting the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship and are used only for the convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.
In the present invention, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being permanently connected, detachably connected, or integral; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on which the present invention is used, or orientations or positional relationships that the present invention is usually placed when the present invention is used, and are used only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the present invention, unless otherwise expressly stated or limited, the first feature may be present on or under the second feature in direct contact with the first and second feature, or may be present in the first and second feature not in direct contact but in contact with another feature between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.
Claims (5)
1. A nodular cast iron traction motor welding process for rail transit is characterized in that: the method comprises the following steps:
1) Cleaning stainless steel at the position of the junction box welded on the traction machine shell by using alcohol before welding;
2) The air conditioner and the heating device are used for temperature control in the welding room;
3) Preheating a ferronickel welding rod in a heating furnace to 180 ℃; measuring by using a contact type temperature measuring instrument;
4) Preheating flame at the position of the traction machine shell for welding the junction box to 180 ℃; measuring by using a contact type temperature measuring instrument;
5) Fixing the junction box on the traction casing by using screws and then welding, wherein through repeated experiments, the welding needs to use an Isa import nickel-iron welding rod OK92.58; the material has better matching property with two parent materials; the length of the riveting spot is 3 cm;
6) Polishing the welding seam with the height of 2/3 of the rivet welding seam after welding; the molding of appearance welding seams is facilitated;
7) After polishing, measuring the temperature of a welding position and a base metal, wherein the temperature cannot be lower than 180 ℃; measuring by using a contact type temperature measuring instrument;
8) Formal welding, wherein a welding rod with the welding angle A4 and the diameter of 2.5 can only be used for 1/3 of the length, the welding rod is burnt due to overheating, and the welding type is reduced; controlling the length of a welding seam;
9) The arc welding is stopped, and the arc crater must be filled to prevent the arc crater from cracking; after welding one section, immediately knocking the steel bar by using a welding seam knocking air hammer, wherein the end part of the knocking hammer is required to be hemispherical, knocking the semi-molten welding seam to be equal to secondary forging, so that stress can be removed, and a solidification crystalline structure and a solid phase change structure can be improved; the toughness and the fatigue resistance of the welding seam are improved, so that the risk of cracking of the welding seam is eliminated;
10 Heat welding and heat affected zone with flame after knocking is completed, the temperature is more than or equal to 300 ℃; the quick dehydrogenation treatment is realized; preventing the generation of hydrogen induced cracks;
11 Carrying out heat preservation treatment immediately after dehydrogenation treatment, and carrying out heat preservation and slow cooling by using an industrial heat blanket until welding is finished;
12 Putting the shell into a tempering furnace for tempering treatment, and naturally cooling the furnace body with the temperature of the furnace to be below 100 ℃ for opening the furnace after the tempering treatment is finished;
13 The shell is subjected to aging vibration after being taken out of the furnace, so that stress is eliminated, crystal grains are refined, and the strength is improved;
14 Sand blasting treatment after discharging to remove surface impurities;
15 PT penetration detection is carried out on the welding position of the machine shell; defects are found and welding repair is carried out, preheating is needed before repair, positions where PT penetrating fluid leaks must be ground off, and then welding is carried out.
2. The welding process of the ductile cast iron traction motor for rail transit according to claim 1, characterized in that: in the step 2), the temperature is controlled to be more than 15 ℃, and the humidity is less than or equal to 30%.
3. The welding process of the ductile cast iron traction motor for rail transit according to claim 1, characterized in that: in the step 8), the length of the welding seam can be welded for 2.5-3 cm.
4. The welding process of the ductile cast iron traction motor for rail transit according to claim 1, characterized in that: in the step 15), repairing welding, and repeating the steps 1-15 in the welding process.
5. The welding process of the ductile cast iron traction motor for rail transit according to claim 1, characterized in that: the parent metal is a traction machine shell and a junction box.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211250832.XA CN115401428A (en) | 2022-10-13 | 2022-10-13 | Nodular cast iron traction motor welding process for rail transit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211250832.XA CN115401428A (en) | 2022-10-13 | 2022-10-13 | Nodular cast iron traction motor welding process for rail transit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115401428A true CN115401428A (en) | 2022-11-29 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211250832.XA Pending CN115401428A (en) | 2022-10-13 | 2022-10-13 | Nodular cast iron traction motor welding process for rail transit |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4534793A (en) * | 1979-09-19 | 1985-08-13 | Research Corporation | Cast iron welding materials and method |
| JPH07214313A (en) * | 1994-01-31 | 1995-08-15 | Kuroki Kogyosho:Kk | Weld repairing method for high cr cast iron product |
| CN101357429A (en) * | 2007-08-03 | 2009-02-04 | 上海船厂船舶有限公司 | Welding repair method of iron casting |
| CN101774070A (en) * | 2009-12-30 | 2010-07-14 | 山东大学 | Micro-plasma arc welding for heat-resistant casting alloy and austenitic stainless steel |
| CN109396612A (en) * | 2018-12-10 | 2019-03-01 | 中石化第十建设有限公司 | A kind of UNS N08825 nickel-base material pipeline solid core welding wire consumable electrode pulse MIG welding procedure |
| CN112475786A (en) * | 2020-10-22 | 2021-03-12 | 陕西铁路工程职业技术学院 | Welding method of stainless steel/carbon steel laminated structure composite board |
-
2022
- 2022-10-13 CN CN202211250832.XA patent/CN115401428A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4534793A (en) * | 1979-09-19 | 1985-08-13 | Research Corporation | Cast iron welding materials and method |
| JPH07214313A (en) * | 1994-01-31 | 1995-08-15 | Kuroki Kogyosho:Kk | Weld repairing method for high cr cast iron product |
| CN101357429A (en) * | 2007-08-03 | 2009-02-04 | 上海船厂船舶有限公司 | Welding repair method of iron casting |
| CN101774070A (en) * | 2009-12-30 | 2010-07-14 | 山东大学 | Micro-plasma arc welding for heat-resistant casting alloy and austenitic stainless steel |
| CN109396612A (en) * | 2018-12-10 | 2019-03-01 | 中石化第十建设有限公司 | A kind of UNS N08825 nickel-base material pipeline solid core welding wire consumable electrode pulse MIG welding procedure |
| CN112475786A (en) * | 2020-10-22 | 2021-03-12 | 陕西铁路工程职业技术学院 | Welding method of stainless steel/carbon steel laminated structure composite board |
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