CN113751829A - Welding process of flange and pipe - Google Patents
Welding process of flange and pipe Download PDFInfo
- Publication number
- CN113751829A CN113751829A CN202111080125.6A CN202111080125A CN113751829A CN 113751829 A CN113751829 A CN 113751829A CN 202111080125 A CN202111080125 A CN 202111080125A CN 113751829 A CN113751829 A CN 113751829A
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- CN
- China
- Prior art keywords
- welding
- flange
- pipe
- main body
- chuck
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000003466 welding Methods 0.000 title claims abstract description 152
- 238000000034 method Methods 0.000 title claims abstract description 41
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 32
- 238000007789 sealing Methods 0.000 claims abstract description 23
- 229910052786 argon Inorganic materials 0.000 claims abstract description 16
- 210000001503 joint Anatomy 0.000 claims abstract description 16
- 230000000149 penetrating effect Effects 0.000 claims description 4
- 238000003754 machining Methods 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 5
- 230000000873 masking effect Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000005498 polishing Methods 0.000 description 2
- 238000009417 prefabrication Methods 0.000 description 2
- 239000012945 sealing adhesive Substances 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 239000002390 adhesive tape Substances 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 210000000078 claw Anatomy 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
Images
Classifications
-
- 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
- B23K9/02—Seam welding; Backing means; Inserts
- B23K9/028—Seam welding; Backing means; Inserts for curved planar seams
- B23K9/0282—Seam welding; Backing means; Inserts for curved planar seams for welding tube sections
-
- 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
-
- 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
-
- 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
- B23K9/32—Accessories
-
- 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
- B23K9/32—Accessories
- B23K9/325—Devices for supplying or evacuating shielding gas
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
Abstract
The invention provides a welding process of a flange and a pipe, and belongs to the technical field of welding processes. The welding machine solves the problems of low welding efficiency and high welding labor intensity of the existing flange and pipe. The welding process of the flange and the pipe comprises the following steps: step A: fixing the butt joint position of the flange and the inner end of the pipe by spot welding; and B: the welding seam at the butt joint position of the flange and the pipe is wrapped in a whole circle by using the figure paper, the outer ends of the flange and the pipe are blocked by sealing elements, and argon can enter the inner cavities of the flange and the pipe through the sealing elements at the outer ends of the pipe; and C: fixing a flange on a rotatable chuck, driving the flange and a pipe to rotate through the chuck and welding a welding seam, wherein the welding position is a flat welding position; step D: and (4) taking down the welded flange and the welded pipe, and storing after removing the sealing piece. The welding process of the flange and the pipe has the advantages of ensuring the welding quality and improving the welding efficiency.
Description
Technical Field
The invention belongs to the technical field of welding processes, and relates to a welding process of a flange and a pipe.
Background
The prefabrication of the pipeline is to perform the work of pipeline design, prefabrication management, pipeline cutting, pipeline groove processing, welding, logistics, anti-corrosion paint, pipeline flaw detection and the like in a fixed area.
In the prefabricated field of pipeline, flange and pipe need be organized and the welding, and current welding mode is: firstly processing and cleaning the welding part of the flange and the pipe, then flatly placing the flange on a workbench, fixing the flange and the pipe in a spot welding mode, then manually rotating the flange and the pipe by a welder when the welder aligns the welding line with a welding gun for welding, and then continuously welding, wherein the welding efficiency is low and the labor intensity of welding is high by the manual welding mode when the welder manually rotates the flange and the pipe every 2-3 cm.
Disclosure of Invention
The invention aims to provide a welding process of a flange and a pipe aiming at the problems in the prior art, and solves the technical problem of how to improve the welding efficiency while ensuring the welding quality.
The purpose of the invention can be realized by the following technical scheme: a process for welding a flange to a pipe, the process comprising the steps of:
step A: machining and polishing the butt joint position of the flange and the inner end of the pipe, and fixing the butt joint position of the flange and the inner end of the pipe through spot welding;
and B: the welding seam at the butt joint position of the flange and the pipe is wrapped in a whole circle by using the figure paper, the outer ends of the flange and the pipe are blocked by sealing elements, and argon can enter the inner cavities of the flange and the pipe through the sealing elements at the outer ends of the pipe;
and C: fixing a flange on a rotatable chuck, driving the flange and a pipe to rotate through the chuck and welding a welding seam, wherein the welding position is twelve points, and the welding position is a flat welding position;
step D: the welded flange and pipe are removed from the chuck, and the seal is removed and stored.
The welding process wraps the welding seam in a whole circle through the masking paper, the masking paper plays a role in protecting the welding seam, the welding seam is prevented from being polluted, and the welding quality is guaranteed. During welding, beautiful line paper can burn out naturally, can not the adhesion in the welding seam, can not influence the welding seam quality, and beautiful line paper can cooperate the sealing member to play sealed effect to argon gas simultaneously, makes argon gas can not too much leak, and the back has argon protection all the time when making the welding, improves welding quality. The welding process has the advantages that the chuck drives the flange and the pipe to rotate and welds the welding seam, the operation that a welder manually rotates the pipe and the flange is avoided, the stability of the welding seam is ensured, the welding quality is ensured, the welding position is in a twelve-point position, the welding position is a flat welding position, namely, the welder does not need to move a welding wire and a welding gun by a large margin during welding, the labor intensity of the welder during welding is reduced, meanwhile, the instability caused in the process of moving by a large margin is avoided, and the welding quality is ensured. This welding process welds pipe and flange through semi-automatization's mode, and protects the welding seam through beautiful line paper and argon gas in welding process, improves welding efficiency when guaranteeing welding quality, reduces welder's intensity of labour, simultaneously with the flange fix on rotatable chuck can, need not extra customization equipment, with low costs.
In the welding process of the flange and the pipe, in the step A, the butt joint position of the flange and the inner end of the pipe is turned by a lathe to form an outer groove, and the gradient of the outer groove is 25-35 degrees. The butt joint position of the flange and the pipe is provided with enough welding seams, and the connecting strength of the flange and the pipe is improved.
In the welding process of the flange and the pipe, in the step A, the pairing gap of the flange and the pipe is between 2 and 3 mm. The butt joint position of the flange and the pipe is provided with enough welding seams, and the connecting strength of the flange and the pipe is improved.
In the above welding process of the flange and the pipe, in the step a, the spot welding mode is argon arc welding, and the number of the spot welding may be four points, eight points or twelve points. The flange and the pipe are accurately pre-positioned, and the connecting strength is sufficient.
In the welding process of the flange and the pipe, in the step B, the sealing element for sealing the outer end of the pipe comprises a main body and a sealing tape wound around the circumference of the main body, the main body is partially embedded into the pipe, the sealing tape seals a gap between the main body and the pipe, and an inflation tube penetrating through the main body is arranged in the main body. The main part can be made by metal material, and the gas tube is worn to establish fixedly and runs through the main part simultaneously, seals through inserting sealed mode promptly, and is sealed convenient.
In the above welding process for the flange and the pipe, in the step C, the chuck includes a turntable and a plurality of jaws which are arranged on the turntable and can move along the turntable, and the flange can be fixed between the plurality of jaws. The chuck has simple structure, does not need additional customization equipment and has low cost.
In the above welding process of the flange and the pipe, in the step C, a gap is formed between the flange and the turntable. The structure is not easy to damage the flange, and simultaneously provides enough space for sealing the sealing element at the outer end of the flange.
In the welding process of the flange and the pipe, in the step C, the welding current is 130-170A, the welding voltage is 12-18V, and the welding speed is 15-18 min/m.
In the welding process of the flange and the pipe, in the step C, the welding mode is argon arc welding, and backing welding is firstly carried out during welding, and then filling and capping are carried out. The flange and the pipe rotate for multiple circles, multiple welding seams are welded, and welding strength is improved.
In the welding process of the flange and the pipe, the flange is a WN flange, the cross section of the pipe is in a circular ring shape, and the length of the pipe is 10-50 cm. The length of the tube is relatively short and no support is required for the tube during welding.
Compared with the prior art, the welding process of the flange and the pipe provided by the invention has the following advantages:
1. the welding process has the advantages that the chuck drives the flange and the pipe to rotate and welds a welding seam, the operation that a welder manually rotates the pipe and the flange is avoided, the welder does not need to move a welding wire and a welding gun by a large margin, the labor intensity of the welder is reduced, the welding quality is guaranteed, and the welding efficiency is improved.
2. The welding process wraps the welding seam in a whole circle through the masking paper, the welding seam is prevented from being polluted, meanwhile, the masking paper can be matched with the sealing piece, so that argon cannot be excessively leaked, the back surface is always protected by the argon during welding, and the welding quality is guaranteed.
3. The welding process can fix the flange on the rotatable chuck, does not need additional customized equipment and is low in cost.
Drawings
FIG. 1 is a view showing a state in which the flange and the pipe are welded to each other.
FIG. 2 is a schematic view of the present flange and pipe weld.
In the figure, 1, a flange; 2. a tube; 3. a seal member; 31. a main body; 32. sealing the adhesive tape; 4. a chuck; 41. a turntable; 42. a claw; 5. and an inflation tube.
Detailed Description
The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.
As shown in fig. 1 and 2, the welding process of the flange 1 and the pipe 2 comprises the following steps:
step A: machining and polishing the butt joint positions of the inner ends of the flange 1 and the pipe 2, and fixing the butt joint positions of the inner ends of the flange 1 and the pipe 2 by spot welding in an argon arc welding mode. Specifically, the flange 1 is a WN flange 1, the cross section of the pipe 2 is circular, the butt joint position of the flange 1 and the inner end of the pipe 2 is turned out with a lathe to form an outer groove, and then burrs are ground. In this embodiment, the slope of the outer groove is 30 °, the pairing gap between the flange 1 and the pipe 2 is 2.5mm, the number of spot welding may be eight points, and the length of the pipe 2 is 30cm, in actual production, the slope of the outer groove may be 25 ° or 35 °, the pairing gap between the flange 1 and the pipe 2 may be 2mm or 3mm, the number of spot welding may be four points or twelve points, and the length of the pipe 2 may be 10cm or 50 cm.
And B: the welding seam at the butt joint position of the flange 1 and the pipe 2 is wrapped completely by the masking paper, the outer ends of the flange 1 and the pipe 2 are sealed and blocked by the sealing element 3, the sealing element 3 for blocking the outer end of the pipe 2 comprises a main body 31 and a sealing adhesive tape 32 wound on the circumference of the main body 31, the main body 31 is partially embedded into the pipe 2, the sealing adhesive tape 32 seals a gap between the main body 31 and the pipe 2, an inflation tube 5 penetrating through the main body 31 is fixedly arranged in the main body 31 in a penetrating mode, and argon can enter the inner cavities of the flange 1 and the pipe 2 through the inflation tube 5.
And C: the flange 1 is fixed on a rotatable chuck 4, the chuck 4 comprises a rotary table 41 and clamping jaws 42 which are arranged on the rotary table 41 and can move along the rotary table 41, in the embodiment, the number of the clamping jaws 42 is three, and in the actual production, the number of the clamping jaws 42 can be four or six. The flange 1 can be fixed between three jack catchs 42, and flange 1 is fixed the back, has the clearance between flange 1 and the carousel 41, and through driver for example motor drive chuck 4 rotatory, chuck 4 is rotatory to be driven flange 1 and pipe 2 rotatory and weld the seam through welder and welding wire, and the welded mode is argon arc welding, and the welding position is in twelve dot positions, and the welding position is the flat welding position, and backing weld is carried out earlier during the welding, fills and the capping again. In this embodiment, the welding current is 150A, the welding voltage is 15V, the welding speed is 16.5min/m, and the number of times of filling is one, in actual production, the welding current may be 130A or 170A, the welding voltage may be 12V or 18V, the welding speed is 15min/m or 18min/m, and the number of times of filling may be two or three, or may not be performed.
Step D: the welded flange 1 and pipe 2 are removed from the chuck 4, and the seal 3 is removed and stored.
And repeating the steps to complete the welding of the plurality of flanges 1 and the pipes 2.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.
Although the terms flange 1, tube 2, seal 3, body 31, sealing tape 32, chuck 4, dial 41, jaws 42, gas tube 5, etc. are used more herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.
Claims (10)
1. A process for welding a flange to a pipe, the process comprising the steps of:
step A: machining and grinding the butt joint positions of the inner ends of the flange (1) and the pipe (2), and fixing the butt joint positions of the inner ends of the flange (1) and the pipe (2) through spot welding;
and B: the welding seam at the butt joint position of the flange (1) and the pipe (2) is completely wrapped by the figure paper, the outer ends of the flange (1) and the pipe (2) are blocked by the sealing element (3), and argon can enter the inner cavities of the flange (1) and the pipe (2) through the sealing element (3) at the outer end of the pipe (2);
and C: fixing a flange (1) on a rotatable chuck (4), driving the flange (1) and a pipe (2) to rotate through the chuck (4) and welding a welding seam, wherein the welding position is at a twelve-point position, and the welding position is a flat welding position;
step D: the welded flange (1) and pipe (2) are removed from the chuck (4), and the seal (3) is removed and stored.
2. A flange and pipe welding process according to claim 1, wherein in the step A, the butt joint position of the flange (1) and the inner end of the pipe (2) is turned with a lathe to form an outer bevel, and the gradient of the outer bevel is 25-35 degrees.
3. A flange and pipe welding process according to claim 1, wherein in step a, the pairing gap between the flange (1) and the pipe (2) is between 2 and 3 mm.
4. A flange and pipe welding process according to claim 1, 2 or 3, wherein in step A, the spot welding mode is argon arc welding, and the number of the spot welding can be four points, eight points or twelve points.
5. A flange and tube welding process according to claim 1, 2 or 3, wherein in step B, the sealing member (3) for sealing the outer end of the tube (2) comprises a main body (31) and a sealing tape (32) wound around the main body (31), the main body (31) is partially embedded in the tube (2), the sealing tape (32) seals the gap between the main body (31) and the tube (2), and the main body (31) is penetrated by the inflation tube (5) penetrating through the main body (31).
6. A process for welding flanges and pipes according to claim 1, 2 or 3, wherein in step C, the chuck (4) comprises a turntable (41) and a plurality of jaws (42) arranged on the turntable (41) and movable along the turntable (41), the flange (1) being fixable between the jaws (42).
7. A flange and pipe welding process according to claim 6, wherein in step C, there is a gap between the flange (1) and the turntable (41).
8. A flange and pipe welding process as claimed in claim 1, 2 or 3, wherein in step C, the welding current is 130-170A, the welding voltage is 12-18V, and the welding speed is 15-18 min/m.
9. A flange and pipe welding process according to claim 1, 2 or 3, wherein in the step C, the welding mode is argon arc welding, and backing welding is firstly carried out during welding, and then filling and facing are carried out.
10. A flange and pipe welding process according to claim 1, 2 or 3, characterized in that the flange (1) is a WN flange, the cross section of the pipe (2) is circular ring-shaped, and the length of the pipe (2) is between 10-50 cm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111080125.6A CN113751829A (en) | 2021-09-15 | 2021-09-15 | Welding process of flange and pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111080125.6A CN113751829A (en) | 2021-09-15 | 2021-09-15 | Welding process of flange and pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113751829A true CN113751829A (en) | 2021-12-07 |
Family
ID=78795778
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111080125.6A Pending CN113751829A (en) | 2021-09-15 | 2021-09-15 | Welding process of flange and pipe |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113751829A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58181482A (en) * | 1982-04-16 | 1983-10-24 | Mitsubishi Heavy Ind Ltd | Welding device of pipe and flange |
| JPH07214309A (en) * | 1994-02-03 | 1995-08-15 | Nippon Steel Corp | Method for welding steel tube |
| JPH1085987A (en) * | 1996-09-19 | 1998-04-07 | Iwai Kikai Kogyo Kk | Internal face gas shield jig for welding tube |
| CN201702498U (en) * | 2010-04-20 | 2011-01-12 | 中国十七冶集团有限公司 | Board-stopping device used for gas shielded welding of large-caliber pipeline and long pipeline |
| CN203696208U (en) * | 2014-03-06 | 2014-07-09 | 中国化学工程第十一建设有限公司 | Argon filling protection mechanism for minor-caliber pipeline welding |
| CN209850081U (en) * | 2019-03-06 | 2019-12-27 | 渤海造船厂集团有限公司 | Argon filling device for tungsten electrode argon arc welding practical operation training pipe fitting |
| CN212384958U (en) * | 2020-05-26 | 2021-01-22 | 嘉兴开天传动技术有限公司 | Flange pipe spin welding frock |
| CN213615096U (en) * | 2020-07-16 | 2021-07-06 | 江苏良工精密合金钢有限公司 | Automatic welding device for pipe fitting flange |
-
2021
- 2021-09-15 CN CN202111080125.6A patent/CN113751829A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58181482A (en) * | 1982-04-16 | 1983-10-24 | Mitsubishi Heavy Ind Ltd | Welding device of pipe and flange |
| JPH07214309A (en) * | 1994-02-03 | 1995-08-15 | Nippon Steel Corp | Method for welding steel tube |
| JPH1085987A (en) * | 1996-09-19 | 1998-04-07 | Iwai Kikai Kogyo Kk | Internal face gas shield jig for welding tube |
| CN201702498U (en) * | 2010-04-20 | 2011-01-12 | 中国十七冶集团有限公司 | Board-stopping device used for gas shielded welding of large-caliber pipeline and long pipeline |
| CN203696208U (en) * | 2014-03-06 | 2014-07-09 | 中国化学工程第十一建设有限公司 | Argon filling protection mechanism for minor-caliber pipeline welding |
| CN209850081U (en) * | 2019-03-06 | 2019-12-27 | 渤海造船厂集团有限公司 | Argon filling device for tungsten electrode argon arc welding practical operation training pipe fitting |
| CN212384958U (en) * | 2020-05-26 | 2021-01-22 | 嘉兴开天传动技术有限公司 | Flange pipe spin welding frock |
| CN213615096U (en) * | 2020-07-16 | 2021-07-06 | 江苏良工精密合金钢有限公司 | Automatic welding device for pipe fitting flange |
Non-Patent Citations (1)
| Title |
|---|
| 《职业技能鉴定教材》编审委员会: "《电焊工》", 30 November 1996, 中国劳动出版社 * |
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| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
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Application publication date: 20211207 |