CN115507247A - Fully automatic welding method and equipment for pressure repair of in-service oil and gas pipelines - Google Patents

Abstract

The invention relates to the technical field of welding, in particular to a full-automatic welding method and full-automatic welding equipment for repairing an in-service oil and gas pipeline under pressure, and aims to solve the technical problem that the existing manual arc welding and automatic welding processes cannot completely meet the welding requirement for repairing and welding a steel pipeline under pressure. The method comprises the following steps of welding transverse welding channels: one automatic welding machine welds from a first starting point of the first transverse bead along a first direction, and the other automatic welding machine welds from a second starting point of the second transverse bead along a second direction; wherein the first direction is opposite to the second direction, the first starting point is an upstream end point of the first transverse bead, and the second starting point is a downstream end point of the second transverse bead. This scheme can realize pressing in labour oil gas pipeline and repair the welding.

Description

Fully automatic welding method and equipment for pressure repair of in-service oil and gas pipelines

technical field

The invention relates to the field of welding technology, in particular to a fully automatic welding method and equipment for pressure repair of in-service oil and gas pipelines.

Background technique

With the continuous construction and development of long-distance oil and gas pipelines and urban pipeline networks, the workload of pipeline maintenance and welding construction continues to increase.

At present, the method of hot-press repair welding for steel oil and gas pipelines is manual arc welding. However, the existing manual arc welding has the following problems: the welding efficiency is low, and the welding quality is greatly influenced by the subjective factors of the welding operators. Especially for high-grade and large-diameter pipelines, the welding workload under pressure repair is heavy, and the welding quality of manual welding is difficult to guarantee for long-term high-strength welding operations.

At the same time, the existing automatic welding process mainly for non-pressure pipelines cannot be used for the repair of steel oil and gas pipelines under pressure. On the one hand, due to the presence of the medium in the oil and gas pipelines under pressure, the conventional preheating temperature cannot achieve the expected effect; on the other hand On the one hand, the conventional automatic welding process is to weld from the upstream end of the two horizontal welds to the downstream end at the same time. This method will cause the downstream ends of the two horizontal welds to be stretched by force, making it difficult to weld the horizontal welds at the downstream end. Increase, and it is very easy to cause problems such as cracks and burn-through of pores on the pressurized oil and gas pipeline.

In summary, neither manual arc welding nor the existing automatic welding process can fully meet the welding requirements for the repair and welding of steel pipelines under pressure.

Contents of the invention

The purpose of the present invention is to provide a fully automatic welding method and equipment for repairing oil and gas pipelines under pressure to solve the technical problem that the existing manual arc welding and automatic welding processes cannot fully meet the welding requirements for repairing steel pipelines under pressure.

In order to solve the problems of the technologies described above, the technical solution provided by the invention is:

A fully automatic welding method for in-service oil and gas pipeline under pressure repair, which is used to weld the sleeve to the defect position of the pipeline under pressure. The adjacent parts of the sleeve form the first transverse bead and the second transverse bead respectively, and the method comprises the steps of welding the transverse bead:

One of the automatic welding machines welds along the first direction from the first starting point of the first horizontal welding run, and at the same time, the other automatic welding machine welds along the second direction from the second starting point of the second horizontal welding run;

Wherein, the first direction is opposite to the second direction, the first starting point is the upstream end point of the first horizontal welding bead, and the second starting point is the downstream end point of the second horizontal welding bead.

go a step further,

It also includes cleaning steps: clean and peel off the anticorrosion layer of the pipeline at the place where the in-service steel pipeline needs to be repaired. Flame or cold removal method is used for the stripping. The scope of removing the anticorrosion layer is 500mm outward and 50mm inward along the girth weld position.

go a step further,

It also includes a re-measurement step of the pipe wall thickness: use an ultrasonic thickness gauge to determine the true wall thickness of the pipe.

go a step further,

It also includes the surface cushion welding step. The welding adopts automatic welding and welding of the cushion. The width of the cushion is not less than 5, and the thickness is 1mm-2.3mm. The fully automatic welding joint is angle pendulum.

go a step further,

In the horizontal bead welding step, the sleeve installation step is also included:

The sleeve covers the defective position on the pipeline and places the defective position at the center of the sleeve;

Use U-shaped clips to fix the upper and lower sleeves, and adjust the coaxiality between the sleeve and the pipe through the wedge iron.

go a step further,

It also includes a preheating step: perform transverse alignment of the groove, sleeve position, and pipe preheating, and the preheating adopts intermediate frequency heating or flame heating.

go a step further,

Also includes fillet weld steps:

One of the annular welds formed by the sleeve and the pipe is the first annular weld, and the other annular weld formed by the sleeve and the pipe is the second annular weld;

The first annular weld is divided into 12 positioning points by clock points, and the second circular weld is divided into 12 positioning points by clock points;

The first annular weld is welded clockwise from the 12 o'clock position to the 6 o'clock position, the second annular weld is welded counterclockwise from the 12 o'clock position to the 6 o'clock position, and finally the two weld bead joints overlap at the 6 o'clock position .

go a step further,

Fillet weld steps are used for root sealing, filling and capping.

go a step further,

The fillet weld step also includes:

When the groove of the sleeve ring is straight and the wall thickness of the sleeve exceeds 1.4 times the wall thickness of the running pipe, the excess part is transitioned at an angle of 45 degrees.

A device adopting the above-mentioned fully automatic welding method for pressure repair of in-service oil and gas pipelines.

Since the present invention provides a fully automatic welding method for pressure repair of in-service oil and gas pipelines, the method is used to weld the sleeve to the defect position of the pipeline under pressure, and the sleeve is formed by joining the upper sleeve and the lower sleeve , the adjacent parts of the upper sleeve and the lower sleeve respectively form a first transverse weld bead and a second transverse weld bead, the method includes a transverse bead welding step, specifically:

One of the automatic welding machines welds along the first direction from the first starting point of the first horizontal welding run, and at the same time, the other automatic welding machine welds along the second direction from the second starting point of the second horizontal welding run;

Wherein, the first direction is opposite to the second direction, the first starting point is the upstream end point of the first horizontal welding bead, and the second starting point is the downstream end point of the second horizontal welding bead.

The core scheme of this scheme is the fully automatic opposite welding, so that, on the one hand, various problems caused by manual welding can be avoided; on the other hand, a completely different process method from the existing automatic welding is adopted. The simultaneous welding in opposite directions can avoid the problem of opening of the downstream end in the existing welding in the same direction, so it also solves the problems of cracks on the pipeline and burn-through of pores.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

Fig. 1 is a schematic diagram of sleeve repair weld arrangement in an embodiment of the present invention;

Figure 2 is a schematic diagram of the distribution of wall thickness measurement points at the position of the horizontal weld bead of the pipeline in an embodiment of the present invention (K and H are lateral wall thickness measurement points);

Fig. 3 is the schematic diagram of the welding direction of the transverse weld bead in the embodiment of the present invention;

Fig. 4 is the point distribution diagram of the annular weld bead provided by the embodiment of the present invention;

Fig. 5 is the schematic diagram of the welding direction of the synchronous welding of two annular welds provided by the embodiment of the present invention;

Fig. 6 is a schematic diagram of a fillet weld of a transverse bead provided by an embodiment of the present invention;

Fig. 7 is the welding shaping rendering of existing manual welding;

Fig. 8 is an effect drawing of the automatic welding method provided in this embodiment.

Icons: 100-sleeve; 200-pipe;

310-the first transverse weld bead; 320-the second transverse weld bead;

410—the first circular weld; 420—the second circular weld.

detailed description

At present, the method of welding under pressure for the steel oil and gas pipeline 200 is manual arc welding. However, the existing manual arc welding has the following problems: the welding efficiency is low, and the welding quality is greatly influenced by the subjective factors of the welding operators. Especially for the high-grade large-diameter pipeline 200, the welding workload under pressure repair is heavy, and the long-term high-strength welding operation makes it difficult to guarantee the welding quality of manual welding. At the same time, the repair of the steel oil and gas pipeline 200 under pressure cannot use the existing automatic welding process mainly for the non-pressure pipeline 200. On the one hand, due to the presence of the medium in the oil and gas pipeline 200 under pressure, the conventional preheating temperature cannot reach expectations effect; on the other hand, the conventional automatic welding process is to weld from the upstream end to the downstream end of the two transverse welds at the same time, which will cause the downstream ends of the two transverse welds to open under stress, resulting in the downstream end It is more difficult to weld the horizontal bead, and it is very easy to cause problems such as cracks and burn-through of pores on the pressurized oil and gas pipeline 200 .

In view of the above problems, the present invention provides a repair welding method under pressure for an in-service oil and gas pipeline 200, please refer to Fig. 1 to Fig. 8 together.

This method is used to weld the sleeve 100 to the defect position of the pressurized pipeline 200. The sleeve 100 is formed by combining the upper sleeve 100 and the lower sleeve 100, and the upper sleeve 100 and the lower sleeve 100 are adjacent to each other. Partially form a first transverse weld bead 310 and a second transverse weld bead 320 .

The method includes the steps of cross-bead welding, specifically:

One of the automatic welding machines welds along the first direction from the first starting point of the first horizontal welding bead 310, and at the same time, the other automatic welding machine welds along the second direction from the second starting point of the second horizontal welding bead 320 ;

Wherein, the first direction is opposite to the second direction, the first starting point is the upstream end point of the first horizontal welding bead 310, and the second starting point is the downstream of the second horizontal welding bead 320 endpoint.

The core scheme of this scheme is the fully automatic opposite welding, so that, on the one hand, various problems caused by manual welding can be avoided; on the other hand, a completely different process method from the existing automatic welding is adopted. The synchronous welding in opposite directions can avoid the problem of opening of the downstream end existing in the existing same-direction welding, so it also solves the problems of cracks on the pipeline 200, burn-through of pores and the like.

Wherein, with regard to the horizontal bead welding step, specifically, the following steps are included:

S1: Cleaning steps: clean and peel off the anticorrosion layer of the pipeline 200 at the place where the in-service steel pipeline 200 needs to be repaired. Flame or cold removal is used for the stripping. The scope of removing the anticorrosion layer is 500mm outward and 50mm inward along the girth weld position .

S2: Step of re-testing the wall thickness of the pipeline 200: using an ultrasonic thickness gauge to determine the real wall thickness of the pipeline 200.

In this embodiment, the re-measurement of the wall thickness of the pipeline 200 is carried out at the welding position, and the horizontal weld bead is measured along the pipeline 2003 and 6 o'clock positions, and the measurement points are distributed as follows: 3 o'clock positions K1, K2, K3, K4, K5, K6, K7, K8, K9, K10, K11...and H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11 at 9 o'clock, horizontal bead The number of measuring points is generally an odd number and distributed evenly, the number is based on the length of the transverse weld bead, the more measured the actual pipe 200 wall thickness tends to the actual value. Regarding the above-mentioned 3 o'clock position and 9 o'clock position, it should be noted that as shown in Figure 4, the pipe wall thickness measurement points at the upstream fillet weld position are divided into A1, A2, A3, A4, A5, A6, A7, A8, A9 , A10, A11, and A12 downstream fillet weld thickness measuring points are divided into B1, B2, B3, B4, B5, B6, B7, B8, B9, B10, B11, and B12. The number of measuring points is proportional to the pipe diameter. The positions are equally divided by 360°, and there are at least 12. The above-mentioned 3 o'clock position is the connection line between A3 and B3, and the above-mentioned 9 o'clock position is the connection line between A9 and B9.

S3, the surface cushion welding step, the welding adopts automatic welding and welding cushion, the width of the cushion is not less than 5, the thickness is 1mm-2.3mm, and the fully automatic welding joint is angle pendulum. The width of the cushion is based on the height of the fillet weld leg, and the cushion is row welding.

S4. Installation steps of the sleeve 100:

The sleeve 100 wraps the defective position on the pipeline 200, and places the defective position at the center of the sleeve 100;

Fix the upper and lower sleeves 100 with a U-shaped card, and adjust the coaxiality of the sleeves 100 and the pipeline 200 through a wedge iron.

S5. Preheating steps:

Carry out horizontal group alignment of the groove, sleeve 100 position, pipe 200 preheating, preheating adopts intermediate frequency heating or flame heating.

S6. Welding steps: adjust the automatic welding head, adjust the wire feeding speed of the welding wire feeder, adjust welding parameters, current, voltage, welding speed, pressure and flow of shielding gas.

In this embodiment, for horizontal bead welding, two welding operators operate the automatic welding machine at the same time. , heat welding, filling and capping welding, the welders are on both sides of the pipeline 200 axis direction, one welds from the upstream to the downstream of the pipeline 200, and the other welds from the downstream to the upstream of the pipeline 200, and the welding torch of the welding trolley adopts angle way of swinging.

直流反接，上向焊，电流200-240A，电压20-27V，焊接速度在10-11in/min，保护气体为80％Ar+20％CO2，保护气体流速为28-33L/min。In this embodiment, the position of the cushion layer is the welding position of the fillet weld, which is completed by a fully automatic welding process. The cushion layer is not less than 5 layers, and the thickness of the cushion layer is 1mm-2.3mm. The pendulum width is 26mm, and the preheating temperature before welding is not less than 40°C. Two welding operators operate two welding machines at the same time for welding. The welding starts at 6 o'clock. As shown in Figure 5, welders A1 and B1 operate respectively Fully automatic welding equipment welds from 6 o'clock to 12 o'clock. When lapping, it is necessary to grind off the ending point of the first welding, and make a smooth transition, and then carry out the lapping of the two joints. The diameter of the welding wire selected for the cushion layer is

DC reverse connection, upward welding, current 200-240A, voltage 20-27V, welding speed 10-11in/min, shielding gas 80% Ar+20% CO2, shielding gas flow rate 28-33L/min.

直流反接，焊接方向为横向，焊条摆动方式为直拉或者微摆动，电流90-115A，电压20-27V，焊接速度在3.0-4.0in/min。In this embodiment, the root welding process adopts manual arc welding, and the electrode diameter

The DC is reversed, the welding direction is horizontal, the electrode swing mode is straight pull or micro swing, the current is 90-115A, the voltage is 20-27V, and the welding speed is 3.0-4.0in/min.

直流反接，焊接方向为横向，焊条摆动方式为直拉或者微摆动，电流115-130A，电压20-27V，焊接速度在3.0-4.0in/min。In this embodiment, the heat welding process adopts manual arc welding, and the electrode diameter

The DC connection is reversed, the welding direction is horizontal, the electrode swing mode is straight pull or micro swing, the current is 115-130A, the voltage is 20-27V, and the welding speed is 3.0-4.0in/min.

直流反接，焊接方向为横向，自动焊焊接机头为角摆方式，角摆宽度26mm，电流200-250A，电压20-27V，送丝速度270-350in/min，焊接速度在8-10in/min，保护气体为80％Ar+20％CO2，保护气体流速为28-33L/min，焊道层间温度在80℃-150℃。In this embodiment, the filling process adopts an automatic welding process, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 is the filler bead, the wire diameter

DC reverse connection, welding direction is horizontal, automatic welding welding head is angular swing mode, angular swing width 26mm, current 200-250A, voltage 20-27V, wire feeding speed 270-350in/min, welding speed 8-10in/min min, the shielding gas is 80% Ar+20% CO2, the flow rate of the shielding gas is 28-33L/min, and the interpass temperature is 80°C-150°C.

直流反接，焊接方向为横向，自动焊焊接机头为角摆方式，角摆宽度26mm，电流180-235A，电压20-27V，送丝速度270-350in/min，焊接速度在15-20in/min，保护气体为80％Ar+20％CO2，保护气体流速为28-33L/min，焊道层间温度在80℃-150℃。In the present embodiment, the cover surface process adopts an automatic welding process, and 20, 21, 22, 23, and 24 in Fig. 6 are cover surface weld passes, and the diameter of the welding wire

DC reverse connection, welding direction is horizontal, automatic welding welding head is angular swing mode, angular swing width 26mm, current 180-235A, voltage 20-27V, wire feeding speed 270-350in/min, welding speed 15-20in/min min, the shielding gas is 80% Ar+20% CO2, the flow rate of the shielding gas is 28-33L/min, and the interpass temperature is 80°C-150°C.

On the other hand, the present invention also provides a welding process for fillet welds:

One of the annular welds formed by the sleeve 100 and the pipe 200 is the first annular weld 410, and the other annular weld formed by the sleeve 100 and the pipe 200 is the second annular weld 420;

The first annular weld 410 is divided into 12 positioning points by clock points, and the second circular weld 420 is divided into 12 positioning points by clock points;

The first annular weld 410 is welded clockwise from the 12 o'clock position to the 6 o'clock position, the second annular weld 420 is welded counterclockwise from the 12 o'clock position to the 6 o'clock position, and finally the two weld bead joints at the 6 o'clock position lap.

Similar to the horizontal bead welding, the fillet weld also adopts a fully automatic welding method, and the welding directions of the first circular weld 410 and the second circular weld 420 are opposite, specifically: one of them is clockwise, The other is counterclockwise. This method of reverse synchronous welding, on the one hand, can completely avoid various problems caused by manual welding. The position) causes the problem of opening, so there will be problems such as cracks and pores burning through. However, this solution adopts reverse synchronous welding, which will not cause stress to the welding end, so there will be no problem of opening and deformation. Therefore, the problems of cracks on the pipeline 200 and burn-through of pores are well solved.

Regarding the fillet weld step, further, the fillet weld step is used for root sealing, filling and capping.

直流反接，焊接方向为上向，自动焊焊接机头为角摆方式，角摆宽度26mm，电流200-250A，电压20-27V，送丝速度250-300in/min，焊接速度在8-10in/min，保护气体为80％Ar+20％CO2，保护气体流速为25-30L/min，焊道层间温度在50℃-150℃。In this embodiment, the root sealing process adopts the above-mentioned fillet weld steps, and the diameter of the welding wire

DC reverse connection, welding direction is upward, automatic welding welding head is angular swing mode, angular swing width 26mm, current 200-250A, voltage 20-27V, wire feeding speed 250-300in/min, welding speed 8-10in /min, the shielding gas is 80% Ar+20% CO2, the flow rate of the shielding gas is 25-30L/min, and the interpass temperature is 50°C-150°C.

直流反接，焊接方向为横向，自动焊焊接机头为角摆方式，角摆宽度26mm，电流200-250A，电压20-27V，送丝速度270-350in/min，焊接速度在8-10in/min，保护气体为80％Ar+20％CO2，保护气体流速为28-33L/min，焊道层间温度在50℃-150℃。In this embodiment, the filling process adopts the above-mentioned fillet weld steps, and the diameter of the welding wire

DC reverse connection, welding direction is horizontal, automatic welding welding head is angular swing mode, angular swing width 26mm, current 200-250A, voltage 20-27V, wire feeding speed 270-350in/min, welding speed 8-10in/min min, the shielding gas is 80% Ar+20% CO2, the flow rate of the shielding gas is 28-33L/min, and the interpass temperature is 50°C-150°C.

直流反接，焊接方向为横向，自动焊焊接机头为角摆方式，角摆宽度26mm，电流180-235A，电压20-27V，送丝速度270-350in/min，焊接速度在15-20in/min，保护气体为80％Ar+20％CO2，保护气体流速为28-33L/min，焊道层间温度在50℃-150℃。In this embodiment, the capping process adopts the above-mentioned fillet weld steps, and the diameter of the welding wire

DC reverse connection, welding direction is horizontal, automatic welding welding head is angular swing mode, angular swing width 26mm, current 180-235A, voltage 20-27V, wire feeding speed 270-350in/min, welding speed 15-20in/min min, the shielding gas is 80% Ar+20% CO2, the flow rate of the shielding gas is 28-33L/min, and the interpass temperature is 50°C-150°C.

In this embodiment, the circumferential groove of the sleeve 100 is a straight opening, and when the wall thickness of the sleeve 100 exceeds 1.5 times the wall thickness of the running pipeline 200, the excess part is inverted at an angle of 45 degrees for transition. When T1<1.4T2+C, As shown in Figure 7, when T1>1.4T2+C as shown in Figure 8.

In this embodiment, the distance between the edge of the sleeve 100 and the edge of the cushion layer is 3mm-0mm, and the gap between the sleeve 100 and the pipe 200 is adjusted to be uniform.

Embodiment two

This embodiment provides a device that adopts the hot-press repair welding method for the in-service oil and gas pipeline 200 mentioned in Embodiment 1.

Comprehensive effect evaluation, please refer to Fig. 7 and Fig. 8, Fig. 7 is the welding forming effect drawing of the existing manual welding; Fig. 8 is the forming effect drawing of the automatic welding method provided in this embodiment.

It can be seen from the effect diagram that the surface after welding by the existing manual welding method is uneven and has many defects, while the surface after welding by the automatic welding method provided by this embodiment is smooth and smooth.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (10)

1. A fully automatic welding method for in-service oil and gas pipeline under pressure repair, which is used to weld the sleeve to the defect position of the pipeline under pressure. The adjoining parts of the lower sleeve respectively form the first transverse bead and the second transverse bead, which is characterized in that the transverse bead welding step is included: One of the automatic welding machines welds along the first direction from the first starting point of the first horizontal welding run, and at the same time, the other automatic welding machine welds along the second direction from the second starting point of the second horizontal welding run; Wherein, the first direction is opposite to the second direction, the first starting point is the upstream end point of the first horizontal welding bead, and the second starting point is the downstream end point of the second horizontal welding bead. 2. The full-automatic welding method for pressure repair of in-service oil and gas pipelines according to claim 1, characterized in that, It also includes cleaning steps: clean and peel off the anticorrosion layer of the pipeline at the place where the in-service steel pipeline needs to be repaired. Flame or cold removal method is used for the stripping. The scope of removing the anticorrosion layer is 500mm outward and 50mm inward along the girth weld position. 3. The full-automatic welding method for under-pressure repair of in-service oil and gas pipelines according to claim 2, further comprising a step of retesting the wall thickness of the pipeline: using an ultrasonic thickness gauge to determine the true wall thickness of the pipeline. 4. The fully automatic welding method for in-service oil and gas pipeline repair under pressure according to claim 3, characterized in that it also includes a surface cushion welding step, the welding adopts fully automatic welding of the cushion, and the width of the cushion range is not less than 5 channels, the thickness is 1mm-2.3mm, and the fully automatic welding joint is angle pendulum. 5. The full-automatic welding method for in-service oil and gas pipeline repair under pressure according to claim 4, characterized in that, in the step of welding the horizontal bead, the step of installing sleeves is also included: The sleeve covers the defective position on the pipeline and places the defective position at the center of the sleeve; Use U-shaped clips to fix the upper and lower sleeves, and adjust the coaxiality between the sleeve and the pipe through the wedge iron. 6. The fully automatic welding method for in-service oil and gas pipeline under pressure repair according to claim 5, characterized in that it also includes a preheating step: preheating the groove, the position of the sleeve and the pipeline, and the preheating adopts intermediate frequency heating or Flame heating. 7. The full-automatic welding method for under-pressure repair of in-service oil and gas pipelines according to claim 6, further comprising a fillet weld step: One of the annular welds formed by the sleeve and the pipe is the first annular weld, and the other annular weld formed by the sleeve and the pipe is the second annular weld; The first annular weld is divided into 12 positioning points by clock points, and the second circular weld is divided into 12 positioning points by clock points; The first annular weld is welded clockwise from the 12 o'clock position to the 6 o'clock position, the second annular weld is welded counterclockwise from the 12 o'clock position to the 6 o'clock position, and finally the two weld bead joints overlap at the 6 o'clock position . 8. The fully automatic welding method for in-service oil and gas pipeline under pressure repair according to claim 7, characterized in that fillet weld steps are used for root sealing, filling and capping. 9. The full-automatic welding method for pressure repair of in-service oil and gas pipelines according to claim 8, characterized in that the fillet weld step further comprises: When the groove of the sleeve ring is straight and the wall thickness of the sleeve exceeds 1.4 times the wall thickness of the running pipe, the excess part is transitioned at an angle of 45 degrees. 10. A device using the full-automatic welding method for hot-press repair of in-service oil and gas pipelines according to any one of claims 1-9.

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