CN108637513B - Welding method for petroleum and natural gas long-distance conveying pipeline - Google Patents
Welding method for petroleum and natural gas long-distance conveying pipeline Download PDFInfo
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- CN108637513B CN108637513B CN201810468590.9A CN201810468590A CN108637513B CN 108637513 B CN108637513 B CN 108637513B CN 201810468590 A CN201810468590 A CN 201810468590A CN 108637513 B CN108637513 B CN 108637513B
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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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- 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
- B23K37/00—Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups
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Abstract
The invention provides a welding method of a petroleum and natural gas long-distance transmission pipeline, which comprises the following steps: constructing an air dam in the end to be welded of the long-distance conveying pipeline; forming a weld crater by pairing, sealing the weld crater by using a sealing tape to form a sealing layer, arranging an air outlet at the Y o 'clock position of the sealing layer and an air inlet at the X o' clock position according to the clock position, wherein X is more than or equal to 10 and less than 12 or more than 0 and less than or equal to 2, and the height of the Y o 'clock position is not lower than that of the X o' clock position; introducing protective gas through the gas inlet to discharge air; according to the clock point position, root welding, filling welding and cover surface welding are carried out on a welded junction between the Y clock point and the X clock point, and protective gas is continuously introduced in the step; and cooling, stopping ventilation, and then sequentially carrying out root welding, filling welding and cover surface welding on the unwelded part of the welding opening to finally finish the welding of the whole welding opening. The beneficial effects of the invention include: the argon protection filling effect in the welding process is good, the welding quality is good, and the cost is low.
Description
Technical Field
The invention relates to the field of welding of petroleum and natural gas, in particular to a method for welding a long-distance petroleum and natural gas conveying pipeline.
Background
The welding of the petroleum and natural gas long-distance transmission pipeline is mainly to prevent the weld metal and the heat affected zone from being oxidized so as to prevent the corrosion resistance of the pipeline from being reduced; when a line is connected with a head for welding, how to carry out inner argon filling protection on a welding opening of the connection head is the key of success or failure of welding. The current common process is to set an argon inlet and an exhaust port, because of the existence of two gas inlets and outlets, the protection effect of welding is not very ideal, in the welding process, air can gush into the pipe, the root of the welding seam is seriously oxidized, the unqualified welding seam and the cut rewelding are caused, the construction period is prolonged, and manpower and materials are wasted.
Disclosure of Invention
In view of the deficiencies in the prior art, it is an object of the present invention to address one or more of the problems in the prior art as set forth above.
In order to achieve the above object, the present invention provides a welding method of an oil and gas long distance transmission pipeline, which may include the steps of: constructing an air dam in the to-be-welded end of the long-distance conveying pipeline; assembling the ends to be welded of two built-in gas dams to form a weld crater, sealing the weld crater by using a sealing tape to form a sealing layer, arranging a gas outlet at a Y o 'clock position of the sealing layer and a gas inlet at an X o' clock position of the sealing layer according to the clock position, wherein X is more than or equal to 10 and less than 12 or more than 0 and less than or equal to 2, the height of the Y o 'clock position is not lower than that of the X o' clock position, and preferably, the height of the Y o 'clock position is higher than that of the X o' clock position; introducing protective gas into the space inside the weld crater through the gas inlet, so that the air in the space inside the weld crater is discharged from the gas outlet; root welding is carried out on a welded junction between the Y-6 o 'clock and the X-X o' clock according to the clock position to form a backing welding layer, and the protective gas is continuously introduced in the step; cooling the temperature of the backing welding layer to be below 100 ℃, performing filling welding, and continuously introducing the protective gas in the step, wherein a filling welding layer is formed on the backing welding layer; cooling the temperature of the filling welding layer to be below 100 ℃, performing cover surface welding, and continuously introducing the protective gas to form a cover surface layer on the filling welding layer; and reducing the temperature of the cover surface layer to be below 100 ℃ under the condition of continuously introducing protective gas, stopping introducing the protective gas, and sequentially carrying out root welding, filling welding and cover surface welding on the part of the welding opening which is not welded, thereby finally completing the welding of the whole welding opening.
According to an exemplary embodiment on which the present invention is based, the long-distance transportation pipe comprises a pipe of several hundreds to several tens of kilometers, and further comprises a pipe of several kilometers to several tens of kilometers.
According to an exemplary embodiment of the invention, after the ends to be welded of two built-in air dams are assembled, the distance between the air dams and the weld craters is 30-120 mm.
According to an exemplary embodiment on which the present invention is based, the material of which the air dam is constructed may comprise a readily excludable material.
According to an exemplary embodiment on which the present invention is based, the sealing tape may comprise an adhesive tape or an aluminum foil tape.
According to an exemplary embodiment on which the present invention is based, the easily removable material comprises a rubber disc having a diameter equal to or slightly greater than the inner diameter of the long-distance transportation pipe, the rubber disc having a thickness of 2mm to 5 mm.
According to an exemplary embodiment of the present invention, the step of root-welding the crater between Y o ' clock-6 o ' clock-X o ' clock according to the clock position comprises: root welding is carried out on the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions, wherein Z is more than or equal to 5 and less than or equal to 7.
According to an exemplary embodiment on which the present invention is based, the step of performing the fill welding comprises: and filling and welding the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions.
According to an exemplary embodiment on which the present invention is based, the step of performing a facing weld comprises: according to the clock point position, weld joints between the Z o 'clock and the X o' clock are subjected to surface covering welding, and weld joints between the Z o 'clock and the Y o' clock are subjected to surface covering welding.
According to an exemplary embodiment of the present invention, the step of introducing the shielding gas into the space inside the crater through the gas inlet comprises: through the air inlet will be able to carry protective gas's return bend inserts welded junction inner space's bottom lets in through the return bend protective gas, wherein, the end of giving vent to anger of return bend is the platykurtic and includes two flats, respectively is provided with a venthole on two flats, and two ventholes can face each other.
According to an exemplary embodiment of the present invention, before the step of constructing the air dam, the welding method further comprises: and accumulating starch food in the long-distance conveying pipeline at a position close to the air dam to be constructed and far away from the welded junction.
According to an exemplary embodiment on which the invention is based, the welding method further comprises, before root welding, the steps of: and detecting the oxygen content in the space inside the welding opening.
Compared with the prior art, the welding method of the petroleum and natural gas long-distance transmission pipeline has the advantages of good welding quality, low cost and good protective effect of protective gas (such as argon) in the welding process.
Drawings
The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:
fig. 1 shows a schematic radial cross-sectional view of a crater according to another exemplary embodiment of the present invention.
Fig. 2 shows a schematic axial cross-sectional view of the inner space of a crater according to another exemplary embodiment of the invention.
Detailed Description
Hereinafter, the welding method of the oil and gas long distance transmission pipeline of the present invention will be described in detail with reference to the accompanying drawings and exemplary embodiments.
The method for welding the oil and gas long distance transmission pipeline according to the exemplary embodiment of the present invention may include the steps of:
constructing an air dam in the to-be-welded end of the long-distance conveying pipeline; the distance between the air dam and the port to be welded can be 30-120 mm, the specific distance can be determined according to the size of the pipe diameter, the material for constructing the air dam can comprise a material which is easy to remove, for example, a material which is dissolved in water or a material which is easy to remove in a ball passing test, the material which is easy to remove in the ball passing test can comprise a rubber wafer with the diameter equal to or slightly larger than the inner diameter of the long-distance conveying pipeline, and the thickness of the rubber wafer can be 2-5 mm, preferably 3 mm.
Assembling the ends to be welded of two built-in gas dams to form a weld crater, sealing the weld crater by using a sealing tape to form a sealing layer, wherein the inside of the sealing layer is a sealing space, an air outlet (also called an exhaust outlet) is arranged at a Y o 'clock position of the sealing layer according to a clock position, an air inlet is arranged at an X o' clock position of the sealing layer, wherein X is more than or equal to 10 and less than 12 or more than 0 and less than or equal to 2, and the height of the Y o 'clock position is not lower than that of the X o' clock position; preferably, X is 11 or 1 and Y is 12, so that air can be sufficiently discharged when the air outlet is disposed at the 12 o' clock position. The width of the crater can be 1.5-80 mm, further, can be 1.5-50 mm, for example 30 ± 10mm, although the width of the crater is not limited to these ranges, and can be determined according to the thickness of the welded pipe and the form of the groove. The sealing tape may comprise an adhesive tape or an aluminum foil tape.
Since the protection air density is usually higher than the air density, the air outlet or the air outlet is required to be higher than the air inlet to ensure the air in the pipeline to be completely replaced, for example, the air outlet is arranged at the highest point.
Protective gas is introduced into the space inside the welding opening through the air inlet, and the air in the space inside the welding opening is discharged from the air outlet, so that the oxidation of the welding root can be prevented or reduced, and the oxidation of the welding root can cause unqualified welding seams and re-welding cut openings. The space inside the welding opening is a gas protection chamber formed by a gas dam, the end to be welded of the pipeline and a sealing belt; the shielding gas may include inert gases (e.g., argon), carbon dioxide, nitrogen, and the like, which do not readily react to oxidation and have a density greater than air.
Root welding is carried out on a welded junction between the Y-6 o 'clock and the X-X o' clock according to the clock position to form a backing welding layer, and protective gas is continuously introduced in the step. Wherein, the welded junction between the Y o ' clock, the 6 o ' clock and the X o ' clock comprises a welded junction from the Y o ' clock, through the 6 o ' clock and to the X o ' clock, or a welded junction from the X o ' clock, through the 6 o ' clock and to the Y o ' clock; in the step, root welding can be carried out in 2-3 sections, the metal temperature of the welding seam can be reduced by the section welding, and air can be further replaced in the discontinuous welding process of the sections so as to ensure the welding quality.
And reducing the temperature of the priming welding layer to be below 100 ℃, for example 90 +/-5 ℃, performing filling welding, and continuously introducing the protective gas to the priming welding layer. In the step, filling welding can be carried out in 2-3 sections, the metal temperature of the welding seam can be reduced by the section welding, and air can be further replaced in the discontinuous welding process of the sections so as to ensure the welding quality.
And reducing the temperature of the filler welding layer to be below 100 ℃, for example 90 +/-5 ℃, performing cover welding to form a cover layer, and continuously introducing the protective gas. In this step, the cover surface welding can be carried out in 2-3 sections, the metal temperature of the welding seam can be reduced by the section welding, and air can be further replaced in the discontinuous welding process of the sections so as to guarantee the welding quality.
And reducing the temperature of the cover surface layer to be below 100 ℃ under the condition of continuously introducing protective gas, stopping introducing the protective gas, and sequentially carrying out root welding, filling welding and cover surface welding on the part of the welding opening which is not welded, thereby finally completing the welding of the whole welding opening. Wherein, each time the welding of one layer is finished, the cooling can be carried out in time so as to ensure the quality.
In the present embodiment, the oil and gas long distance transportation pipe may include an alloy pipe having corrosion resistance, such as austenitic stainless steel (e.g., 316L, 304), duplex stainless steel (e.g., SAF2205, SAF2507), or nickel-based alloy (e.g., N08825, N06625), or a composite pipe composed of at least two of the above.
In the embodiment, due to the thermal sensitization phenomenon of corrosion-resistant materials such as stainless steel, nickel-based alloy and the like at the temperature of 485-850 ℃, harmful phases can be generated, the performance of the materials is reduced, and the corrosion resistance of the materials is mainly reduced. Therefore, the temperature needs to be rapidly reduced in the welding process, the retention time of the interval of 485-850 ℃ is shortened, and the temperature between welding layers is ensured to be less than 100 ℃ in the welding process so as to accelerate the cooling of the metal of the next welding seam.
In this embodiment, the distance between the air dam and the crater is 30-120 mm, for example, 80 ± 10mm, which can be determined according to the size of the pipe diameter.
In this embodiment, the long-distance transportation pipeline may include a long transportation pipeline with several kilometers to several tens of kilometers, the long-distance transportation pipeline may be formed by welding several tens or even hundreds of short pipelines (usually, the length of a pipeline leaving a factory is about 11.5-12.5 m), and the welding process of a complete oil and gas transportation pipeline is as follows: sequentially assembling and welding each short pipeline from a starting position (namely one end of the complete conveying pipeline to be formed) to an end position (namely the other end of the complete conveying pipeline to be formed); however, due to the restriction of many factors such as construction period, welding efficiency, construction equipment, and time of arrival of materials, it is necessary to divide the construction into N small sections and simultaneously construct the small sections, and then connect the small sections (called joint welding). The invention mainly aims at the internal protection of the pipeline when the pipe is made of stainless steel, nickel-based alloy and the composite pipeline made of the materials is welded at the joint, and particularly aims at the internal protection when the long-distance conveying pipeline with the length of hundreds of meters to thousands of meters is welded.
In this embodiment, the step of root-welding the crater between Y o ' clock-Z o ' clock-X o ' clock according to the clock position may include: root welding is carried out on the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions, wherein Z is more than or equal to 5 and less than or equal to 7, preferably Z is 6, and the two sections of welding can be carried out in a non-sequential order. For example, root welding may be performed from the Z o 'clock position to the X o' clock position of the crater and from the Z o 'clock position to the Y o' clock position of the crater in accordance with the clock position.
The step of performing fill welding may include: and (3) filling and welding the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions, wherein Z is more than or equal to 5 and less than or equal to 7, preferably Z is 6, and the welding of the two sections can be carried out in no sequence. For example, the filling welding can be performed from the Z o 'clock position to the X o' clock position of the crater according to the clock positions, the root welding can be performed from the Z o 'clock position to the Y o' clock position of the crater, and the two sections of welding can be performed without any sequence.
The step of performing a face weld may comprise: according to the clock point position, weld joints between the Z clock and the X clock are subjected to surface covering welding, and weld joints between the Z clock and the Y clock are subjected to surface covering welding, wherein Z is more than or equal to 5 and less than or equal to 7, preferably Z is 6, and the two sections of welding can be performed in no sequence. For example, the cap welding may be performed from the crater Z o 'clock position to the X o' clock position in accordance with the clock position, and the cap welding may be performed from the crater Z o 'clock position to the Y o' clock position in accordance with the clock position. In addition, in order to control welding defects in the welding process, joints should be reduced as much as possible.
In this embodiment, the step of introducing the shielding gas into the space inside the crater through the gas inlet includes: the elbow pipe is stretched into the bottom of the pipeline, the protective gas is introduced, the protective gas is filled in the space to be protected from bottom to top, and the air is discharged from the top air outlet. After the elbow is inserted, all positions except the air inlet and the air outlet are required to be in a sealed state, and then protective gas is introduced.
As shown in FIG. 1, the elbow includes two sections connected in sequence and forming a certain angle, such as a first section and a second section, wherein the first section extends into the interior of the weld crater space, the second section is located outside the weld crater, and the angle between the two sections can be determined according to the actual ventilation condition, for example, the angle can be 60-150 degrees, 130 +/-10 degrees, and the like. The end head of the first section is an air outlet end of the bent pipe, the air outlet end is flat and comprises two flat surfaces, air outlet holes are respectively formed in the two flat surfaces, the two air outlet holes can face each other, and the direction of the protective gas sprayed out from the air outlet holes is perpendicular to the flat surfaces.
The elbow is made of stainless steel elbow, and a carbon steel pipe cannot be adopted, because the carbon steel is contacted with stainless steel or nickel-based materials, weld metal can be polluted, the width of the elbow can be 4-7 mm, preferably 6mm, and the length of the first section of the elbow is determined by the diameter of a welded pipeline, for example, the length of the first section is not easy to exceed 20 mm; the gas outlet of return bend sets up to the platykurtic, and this is because the welding clearance only has 2.5 ~ 3.5mm wide, and the platykurtic is favorable to going deep into smoothly intraductally, conveniently opens the venthole in flat department simultaneously, and two symmetrical ventholes of bent pipe air outlet end flat department more are favorable to the pipeline of discharging the air in the pipeline of welding seam both sides, ensure the welding qualification rate. The bent pipe is simple and convenient to manufacture, can be made of instrument pipe excess materials with proper sizes, and is economical and applicable.
In this embodiment, before the step of constructing the air dam, the welding method may further include: starch food such as steamed bread and the like is accumulated in the long-distance conveying pipeline at a position close to the gas dam to be constructed and far away from the weld crate, so that the pressure in the inner space of the weld crate can be prevented from being too high, the gas dam is collapsed, and the protective gas is prevented from leaking.
In this embodiment, before root welding, the welding method further includes the steps of: detecting the oxygen content in the space inside the welded junction; when the oxygen content is less than 200PPM, the subsequent welding step can be carried out, thus preventing or reducing the influence of oxygen in the internal space of the welding opening on welding. In this step, the oxygen content can be detected by providing an oxygen meter.
In this embodiment, after the welding is completed, the welding method may further include the steps of: and (5) timely carrying out appearance inspection, and inspecting according to the nondestructive testing requirement of the main line welding port after the appearance inspection is qualified.
In another exemplary embodiment of the invention, the argon filling time is adjusted from the argon filling protection only in the root welding stage to the girth welding protection of more than 99% by setting the argon filling position at 11 o' clock, and meanwhile, the self-made argon filling bent pipe is adopted to easily realize the welding protection of the whole pipeline, thereby ensuring the welding quality of the pipeline. Fig. 1 is a schematic radial cross-sectional view of a weld according to an exemplary embodiment of the present invention, in which a shielding gas (e.g., argon) is introduced into an inner space of the weld through a bent pipe to exhaust air, and at the same time, an oxygen content in the inner space of the weld can be detected, and the weld is divided into 3 parts, i.e., 1 part, 2 parts, and 3 parts. Fig. 2 shows a schematic axial cross-section of the inner space of the crater according to the invention, wherein P1 is a sealing strip and P1 is an air dam, the sealing strip, the air dam and a part of the tube forming a closed chamber into which a shielding gas (e.g. argon) can be introduced via a gas inlet and outlet.
In the embodiment, the welding method of the oil and gas long-distance transmission pipeline can comprise the following steps:
(1) as shown in fig. 2, before the pipeline assembly, an air dam is constructed by using a sealing gasket P2 (for example, a rubber sheet with a thickness of 3 mm), then the assembly of the welded junctions is performed, and after the assembly is completed, the circumferential weld joint sealing is performed by using an adhesive tape or an aluminum foil tape P1.
(2) And (3) filling argon by adopting a 6mm stainless steel bent pipe, wherein the argon filling position is positioned in the range of 11-Y o 'clock of the circumferential weld (the length is not more than 20mm), exhausting at the Y o' clock position, and simultaneously detecting the oxygen concentration in the pipeline.
(3) After the oxygen concentration in the pipeline is qualified, as shown in fig. 1, firstly welding the '1 section', namely the range from 6 o 'clock to 11 o' clock, and then welding the '2 section', namely the range from 6 o 'clock to 12 o' clock anticlockwise, wherein the welding seam in the '3 section' range is temporarily not welded and is used for continuously filling argon into the pipeline.
(4) Performing filling welding after the layer temperature is within 100 ℃, and performing welding according to the sequence of 1 section and 2 sections as shown in figure 1; cooling in time after the filling welding is finished, and then finishing the cover surface welding according to the same sequence after cooling;
(5) after the metal temperature of the welding line of the 2-section and the 1-section is reduced to 100 ℃, the argon filling pipeline is pulled out, the root welding, the filling and the welding of the cover surface welding line within the range of the 3-section are completed, but the temperature is required to be reduced in time when one layer is completed, so as to ensure the quality.
In this embodiment, after the welding is completed, the appearance inspection should be performed in time, and after the appearance inspection is qualified, the inspection is performed according to the nondestructive testing requirement of the main line crater.
In this embodiment, the material used to construct the dam should be one that is soluble in water or easily removable during the ball through test.
In this embodiment, the oil and gas long distance transport pipeline may comprise a N08825 nickel-based pipeline.
The method is characterized in that the field cutting of one welded junction needs 2-3 hours (mechanical cold cutting), a short circuit with the length not shorter than 500mm is added, a groove is machined and re-welded, two pipe workers and one welder are matched in the whole process, and a generator and the like are configured. Therefore, the welding cost of the invention is low.
In summary, the welding method for the petroleum and natural gas long-distance transmission pipeline has the advantages that: the protection effect of the protective gas (such as argon) in the welding process is good, the influence of oxygen on the welding quality can be avoided or reduced, the welding quality of the welding part is good, and the cost required by the whole welding method is low.
Although the present invention has been described above in connection with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (9)
1. A welding method for petroleum and natural gas long-distance transmission pipelines is characterized by comprising the following steps:
constructing an air dam in the to-be-welded end of the long-distance conveying pipeline;
assembling the ends to be welded of two built-in gas dams to form a weld crater, sealing the weld crater by using a sealing tape to form a sealing layer, arranging a gas outlet at a Y o 'clock position of the sealing layer and a gas inlet at an X o' clock position according to a clock position, wherein X is more than or equal to 10 and less than 12 or more than 0 and less than or equal to 2, and the height of the Y o 'clock position is not lower than that of the X o' clock position;
introducing protective gas into the space inside the weld crater through the gas inlet, so that the air in the space inside the weld crater is discharged from the gas outlet;
root welding is carried out on a welded junction between the Y-6 o 'clock and the X-X o' clock according to the clock position to form a backing welding layer, and the protective gas is continuously introduced in the step;
cooling the temperature of the backing welding layer to be below 100 ℃, performing filling welding, and continuously introducing the protective gas in the step, wherein a filling welding layer is formed on the backing welding layer;
cooling the temperature of the filling welding layer to be below 100 ℃, performing cover surface welding, and continuously introducing the protective gas to form a cover surface layer on the filling welding layer;
reducing the temperature of the cover surface layer to be below 100 ℃ under the condition of continuously introducing protective gas, stopping introducing the protective gas, and sequentially carrying out root welding, filling welding and cover surface welding on the part, which is not welded, of the welding opening to finally finish welding the whole welding opening;
the long-distance conveying pipeline comprises a pipeline with the length of hundreds of meters to tens of kilometers, and the long-distance conveying pipeline comprises an austenitic stainless steel, duplex stainless steel or nickel-based alloy pipeline or a composite pipe consisting of at least two of the austenitic stainless steel, the duplex stainless steel and the nickel-based alloy;
the step of introducing protective gas into the space inside the crater through the gas inlet comprises the following steps: through the air inlet will be able to carry protective gas's return bend inserts welded junction inner space's bottom lets in through the return bend protective gas, wherein, the end of giving vent to anger of return bend is the platykurtic and includes two flats, respectively is provided with a venthole on two flats, and two ventholes are relative.
2. The welding method for the long-distance petroleum and natural gas conveying pipeline according to claim 1, wherein after the ends to be welded of the two built-in gas dams are assembled, the distance between the gas dam and the welded junction is 30-120 mm.
3. The method for welding long distance petroleum and natural gas pipelines according to claim 1, wherein the material for constructing the dam comprises a readily removable material.
4. The method for welding the petroleum and natural gas long-distance transmission pipeline according to claim 3, wherein the easily-excluded material comprises a rubber disc with a diameter equal to or slightly larger than the inner diameter of the long-distance transmission pipeline, and the thickness of the rubber disc is 2-5 mm.
5. The method for welding the petroleum and natural gas long-distance transmission pipeline according to the claim 1, wherein the step of root-welding the welded junction between the Y-6-X o' clock according to the clock position comprises the following steps:
root welding is carried out on the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions, wherein Z is more than or equal to 5 and less than or equal to 7.
6. The method for welding long distance petroleum and natural gas pipelines according to claim 5, wherein said step of performing filling welding comprises:
and filling and welding the welded junctions between the Z o 'clock and the X o' clock and the welded junctions between the Z o 'clock and the Y o' clock according to the clock positions.
7. The method for welding long distance petroleum and natural gas pipelines according to claim 6, wherein said step of facing welding comprises:
according to the clock point position, weld joints between the Z o 'clock and the X o' clock are subjected to surface covering welding, and weld joints between the Z o 'clock and the Y o' clock are subjected to surface covering welding.
8. The method for welding long distance petroleum and natural gas pipelines according to claim 1, wherein before said step of constructing an air dam, said welding method further comprises:
and accumulating starch food in the long-distance conveying pipeline at a position close to the air dam to be constructed and far away from the welded junction.
9. The method for welding long distance petroleum and natural gas pipelines according to claim 1, wherein before root welding, the method further comprises the steps of:
and detecting the oxygen content in the space inside the welding opening.
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Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100491044C (en) * | 2007-11-23 | 2009-05-27 | 鞍钢建设集团有限公司 | Large caliber aluminium alloy pipeline non-pad tungsten electrode argon arc single face welding and double face shaping method |
| CN104475933A (en) * | 2014-11-11 | 2015-04-01 | 中国十七冶集团有限公司 | Argon-filled protection sealing welding method for argon arc welding for pipeline |
| EP3135422A1 (en) * | 2015-08-22 | 2017-03-01 | METALKO Spolka. z o.o. | Multistage backing gas nozzle |
| CN106077917A (en) * | 2016-08-06 | 2016-11-09 | 天津市滨海新区聚荣科技有限公司 | Butt welding method for pipe with small diameter |
| CN207057882U (en) * | 2017-08-04 | 2018-03-02 | 中国能源建设集团东北电力第一工程有限公司 | A kind of pipeline welding argon-filling device |
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2018
- 2018-05-16 CN CN201810468590.9A patent/CN108637513B/en active Active
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