A protective gas support device for high alloy pipeline welding root

Abstract

The present invention relates to the technical field of high-alloy large-diameter pipeline welding, and in particular to a high-alloy pipeline welding root shielding gas support device, comprising: a positioning pin is fixed on a central support rod; a support structure is arranged on the central support rod, and the support structure includes a shaping ring, a directional movable support rod and a hydraulic support rod, the shaping ring is sleeved on the central support rod, and a plurality of directional movable support rods are distributed along the circumference of the shaping ring, and the two ends of each directional movable support rod are respectively movably connected with the shaping ring and the arc-shaped support belt; one end of the hydraulic support rod is movably connected with the arc-shaped support belt, and the other end of the hydraulic support rod is movably connected with the other end of the hydraulic support rod of the adjacent directional movable support rod; the two sides of the V-shaped air chamber are respectively arranged on the arc-shaped support belts on the first support structure and the second support structure. The device can effectively solve the problem that a special air chamber needs to be made for the back-shielding gas welding of large-diameter pipelines GTAW, and the valve is easily blocked during the operation of the unit.

Description

Technical Field

[0001] The invention relates to the technical field of high-alloy large-diameter pipeline welding, and in particular to a high-alloy pipeline welding root protection gas filling support device. Background Art

[0002] The information disclosed in the background of the invention is only intended to enhance the understanding of the overall background of the invention and should not be necessarily regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] In the welding process of some pipelines with high alloy content, it is necessary to adopt the method of filling the back with protective gas to ensure that the back of the root weld is not oxidized and thus ensure the welding quality. Usually, water-soluble paper or cardboard is used to form a closed air chamber at about 200mm on both sides of the welding part. Since the manufactured closed air chamber has no supporting force and sufficient rigidity, and is affected by the preheating of the pipeline welding, the air chamber filled with protective gas is easily destroyed, thus affecting the overall welding quality. Therefore, the existing high-alloy large-diameter pipeline welding technology still has the following deficiencies: a) The operation is complicated, time-consuming and labor-intensive. b) The tightness of the air chamber cannot be guaranteed, and there is a risk of leakage. c) The waste of argon gas is very serious. d) The manufactured air chamber cannot be recycled, which is easy to cause valve blockage during the unit trial operation, requiring the unit to be shut down for maintenance, which consumes a lot of manpower and material resources. Summary of the invention

[0004] In view of the above-mentioned shortcomings, the present invention provides a high-alloy pipeline welding root shielding gas support device, which can effectively solve the problems of large-diameter pipeline GTAW back shielding gas welding requiring the production of a special gas chamber and the continuous supply of argon gas, which is easy to block the valve during the operation of the unit, and is not conducive to saving construction costs, energy conservation and environmental protection, and low construction efficiency. To achieve the above-mentioned invention purpose, the technical means adopted by the present invention are as follows.

[0005] A high alloy pipe welding root protection gas support device comprises: a central support rod, a positioning pin, a first support structure, a second support structure, an arc-shaped support belt, a V-shaped air chamber, a first pulling rope and a second pulling rope. The central support rod is a circular straight rod, the positioning pin is a right triangle, one end of the acute angle is fixed on the central support rod, and the two right-angled sides of the positioning pin are parallel and perpendicular to the central axis of the central support rod. The first support structure and the second support structure are the same, and both are respectively arranged at the two ends of the central support rod. The first support structure and the second support structure both include a shaping ring, a directional movable support rod and a hydraulic support rod. The shaping ring is sleeved on the central support rod, and a plurality of directional movable support rods are distributed along the circumference of the shaping ring. The two ends of each directional movable support rod are respectively movably connected with the shaping ring and the arc-shaped support belt, and a plurality of arc-shaped support belts form a circular ring structure. One end of the hydraulic support rod is movably connected with the arc-shaped support belt, and the other end of the hydraulic support rod is movably connected with the other end of the hydraulic support rod of the adjacent directional movable support rod. The two sides of the flexible V-shaped air chamber are respectively arranged on the arc-shaped support belts on the first support structure and the second support structure, and the V-shaped air chamber as a whole is an arc-shaped structure matching the pipe to be welded. The first support structure and the second support structure are both connected to a first pulling rope, and the second pulling rope is connected to the central support rod.

[0006] Furthermore, the cross-sectional structure of the V-shaped air chamber includes a V-shaped portion, a first side edge, and a second side edge, wherein the first side edge and the second side edge are respectively connected to the left and right sides of the upper edge of the V-shaped portion, and the first side edge and the second side edge are both perpendicular to the vertical center axis of the V-shaped portion.

[0007] Furthermore, the V-shaped air chamber is made of refractory graphite felt, which has good high temperature resistance and is easy to adapt to the high temperature environment caused by welding.

[0008] Furthermore, there are two positioning pins, corresponding to the first supporting structure and the second supporting structure respectively.

[0009] Furthermore, the arc-shaped support belts are steel belts, and there are gaps between adjacent arc-shaped support belts.

[0010] Furthermore, the first pulling rope and the second pulling rope are both steel wire ropes.

[0011] Furthermore, the central support rod is a hollow metal tube, such as a steel tube, an aluminum alloy tube, etc.

[0012] Furthermore, the movable connection adopts a pin connection method.

[0013] Furthermore, a "V"-shaped structure is formed between adjacent directional movable support rods.

[0014] Furthermore, a "V"-shaped structure is formed between adjacent hydraulic support rods.

[0015] Compared with the prior art, the beneficial technical effects achieved by the present invention mainly include the following parts:

[0016] (1) When argon arc welding is used to prime the joints of high-alloy large-diameter pipes, the V-shaped gas chamber is small and closed, which not only helps to prevent the loss of argon gas, but also can use the back-blowing effect of the argon gas flow in the welding gun to protect the molten pool on the back of the weld. Therefore, even if direct welding is performed, it will not cause oxidation and slag on the back of the base weld, thus ensuring the welding quality, saving the amount of argon gas and improving the construction efficiency.

[0017] (2) When the protective device of the present invention is adopted, since both ends of the hydraulic support rod are movably connected, it is ensured that the supporting structure will not deviate significantly. Both ends of the directional movable support rod are movably connected. When the air chamber is used up, it is only necessary to first pull the steel wire rope to make the first supporting structure and the second supporting structure lose their fulcrums, so that the V-shaped air chamber shrinks and becomes smaller. The second steel wire rope can then be used to drive the central support rod to be pulled out of the pipeline for recovery, thereby ensuring that the supporting structure and the V-shaped air chamber are smoothly withdrawn from the pipeline. This effectively solves the problem that the traditional large-diameter pipeline GTAW back-filling shielding gas welding requires the manufacture of a special air chamber and the continuous supply of argon gas, which is prone to valve clogging during unit operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0019] Figure 1 This is a cross-sectional view of a protective gas support device for the root of a high alloy pipeline weld in an embodiment of the present invention.

[0020] Figure 2 4 is a cross-sectional view of a V-shaped air chamber in an embodiment of the present invention.

[0021] Figure 3 It is a cross-sectional view of a protective gas support device for the root of a high alloy pipeline weld in an embodiment of the present invention.

[0022] Figure 4 for Figure 3 Enlarged view of part A in the middle.

[0023] Figure 5 for Figure 3 Enlarged view of part B in the middle.

[0024] The marks in the above drawings respectively represent: 1-center support rod, 2-positioning pin, 3-first support structure, 4-second support structure, 5-arc-shaped support belt, 6-V-shaped air chamber, 7-first pulling rope, 8-second pulling rope, 9-shaped ring, 10-directional movable support rod, 11-hydraulic support rod, 12-V-shaped part, 13-first side edge, 14-second side edge, 15-pipeline. DETAILED DESCRIPTION

[0025] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0026] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element needs to have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0027] refer to Figure 1-5 , an example of a high alloy pipeline welding root protection gas support device, which mainly includes: a central support rod 1, a positioning pin 2, a first support structure 3, a second support structure 4, an arc support belt 5, a flexible V-shaped air chamber 6, a first pulling rope 7 and a second pulling rope 8. Among them:

[0028] The central support rod 1 is a hollow aluminum alloy tube, and the positioning pin 2 is a right triangle, one end of the acute angle of which is fixed on the central support rod 1, and the two right angle sides of the positioning pin 2 are respectively parallel and perpendicular to the central axis of the central support rod 1. The positioning pins 2 are in two groups, corresponding to the first support structure 3 and the second support structure 4, respectively.

[0029] The first support structure 3 and the second support structure 4 have the same structure. They are respectively arranged at the two ends of the central support rod 1. The first support structure 3 and the second support structure 4 both include a shaping ring 9, a directional movable support rod 10 and a hydraulic support rod 11. The shaping ring 9 is sleeved on the central support rod 1. A plurality of directional movable support rods 10 are distributed along the circumference of the shaping ring 9. The two ends of each directional movable support rod 10 are respectively movably connected with the shaping ring 9 and the arc support belt 5. A plurality of arc support belts 5 form a ring structure. The arc support belt 5 is a steel belt, and there is a gap between adjacent arc support belts 5. One end of the hydraulic support rod 11 is movably connected with the arc support belt 5, and the other end of the hydraulic support rod 11 is movably connected with the other end of the hydraulic support rod 11 of the adjacent directional movable support rod 10. A "V"-shaped structure is formed between the adjacent directional movable support rods 10, and a "V"-shaped structure is formed between the adjacent hydraulic support rods 11. The movably connected adopts the pin connection method.

[0030] The cross-sectional structure of the V-shaped air chamber 6 includes a V-shaped portion 12, a first side edge 13, and a second side edge 14, wherein the first side edge 13 and the second side edge 14 are respectively connected to the left and right sides of the upper edge of the V-shaped portion 12, and the first side edge 13 and the second side edge 14 are both perpendicular to the vertical center axis of the V-shaped portion 12. Both sides of the V-shaped air chamber 6 are respectively arranged on the arc-shaped support belts 5 on the first support structure 3 and the second support structure 4, and the V-shaped air chamber 6 as a whole is an arc-shaped structure matching the pipe to be welded.

[0031] The first supporting structure 3 and the second supporting structure 4 are both connected with a first pulling rope 7 , and the second pulling rope 8 is connected to the central supporting rod 1 . Both the first pulling rope 7 and the second pulling rope 8 are steel wire ropes.

[0032] Furthermore, in another embodiment, the V-shaped air chamber 6 is made of refractory graphite felt, which has good high temperature resistance and is easy to adapt to the high temperature environment caused by welding.

[0033] When in use, the two side edges of the prepared flexible V-shaped air chamber 6 (i.e., the first side edge 13 and the second side edge 14) are respectively fixed on the arc-shaped support belts 5 of the first support structure 3 and the second support structure 4. Before the pipeline is assembled, the first support structure 3 is first pulled over the first positioning pin. Under the support of the positioning pin 3, the hydraulic support rod 11 on the first support structure 3 is fully stretched (at this time, the hydraulic support rod 11 is compressed to facilitate subsequent recovery), and then the V-shaped air chamber 6 is squeezed and tightly fixed on the inner wall on one side of the welding port of the pipeline 15.

[0034] Then, the second supporting structure 4 is placed on the other side of the welding port. The diameters of the first supporting structure 3 and the V-shaped air chamber 6 are smaller than the inner diameter of the pipe when they are not stretched and supported. Therefore, the first supporting structure 3 can be easily placed into the pipe, and then the gap between the two pipes 15 to be welded is adjusted so that there is no misalignment.

[0035] Check whether the first pulling rope 7 and the second pulling rope 8 reserved on the other side of the pipeline 15 are intact, and then use the first pulling rope 7 to pull the second supporting structure 3 over the second positioning pin. Under the support of the positioning pin 3, the hydraulic support rod 11 on the second supporting structure 3 is fully stretched, and then the V-shaped air chamber 6 is squeezed and tightly fixed on the inner wall on the other side of the welding port of the pipeline 13. At this time, the welding port is located above the V-shaped portion 12 of the V-shaped air chamber 6. Since the V-shaped air chamber is small and closed, it not only helps to prevent the loss of argon gas, but also can use the backblowing effect of the argon gas flow in the welding gun to protect the molten pool on the back of the weld. Therefore, even if direct welding is performed, it will not cause oxidation and slag on the back of the base weld, thereby ensuring the welding quality, saving argon gas consumption, and improving construction efficiency.

[0036] When the air chamber is used up, it is only necessary to first pull the steel wire rope to make the first supporting structure 3 and the second supporting structure 4 lose their fulcrums. At this time, the compressed hydraulic support rod 11 is restored, so that the first supporting structure 3 and the second supporting structure 4 shrink and their diameters become smaller. The second steel wire rope can be used to drive the central supporting rod to be pulled out of the pipeline for recovery, thereby ensuring smooth withdrawal of the supporting structure and the V-shaped air chamber from the pipeline. This effectively solves the problem that the traditional large-diameter pipeline GTAW back-filling shielding gas welding requires the manufacture of a special air chamber and the continuous supply of argon gas, which is prone to valve clogging during unit operation.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high alloy pipeline welding root protection gas support device, characterized in that: It includes: a central support rod, a positioning pin, a first support structure, a second support structure, an arc-shaped support belt and a V-shaped air chamber; wherein: the positioning pin is fixed on the central support rod; the first support structure and the second support structure are respectively arranged at two ends of the central support rod, and the first support structure and the second support structure both include a shaping ring, a directional movable support rod and a hydraulic support rod, the shaping ring is sleeved on the central support rod, and a plurality of directional movable support rods are distributed along the circumference of the shaping ring, and the two ends of each directional movable support rod are respectively movably connected with the shaping ring and the arc-shaped support belt, and a plurality of arc-shaped support belts form a circular ring structure; one end of the hydraulic support rod is movably connected with the arc-shaped support belt, and the other end of the hydraulic support rod is movably connected with the other end of the hydraulic support rod of the adjacent directional movable support rod; the two sides of the flexible V-shaped air chamber are respectively arranged on the arc-shaped support belts on the first support structure and the second support structure.

2. The high alloy pipeline welding root shielding gas support device according to claim 1 is characterized in that: The positioning pin is a right triangle, one end of the acute angle of which is fixed on the central support rod, and two right-angled sides of the positioning pin are respectively parallel and perpendicular to the central axis of the central support rod.

3. The high alloy pipeline welding root shielding gas support device according to claim 1 is characterized in that: The V-shaped air chamber as a whole is an arc-shaped structure matching the pipe to be welded.

4. The high alloy pipeline welding root shielding gas support device according to claim 3 is characterized in that: The V-shaped air chamber is made of refractory graphite felt.

5. The high alloy pipeline welding root shielding gas support device according to claim 1 is characterized in that: It also includes a first pulling rope and a second pulling rope, wherein the first supporting structure and the second supporting structure are both connected to the first pulling rope, and the second pulling rope is connected to the central supporting rod.

6. The high alloy pipeline welding root shielding gas support device according to claim 5 is characterized in that: The first pulling rope is a steel wire rope.

7. The high alloy pipeline welding root shielding gas support device according to claim 5 is characterized in that: The second pulling rope is a steel wire rope.

8. The high alloy pipeline welding root shielding gas support device according to claim 1 is characterized in that: There are two positioning pins, corresponding to the first supporting structure and the second supporting structure respectively.

9. The high alloy pipeline welding root shielding gas support device according to claim 1 is characterized in that: The arc-shaped support belts are steel belts, and there are gaps between adjacent arc-shaped support belts.

10. The high alloy pipeline welding root shielding gas support device according to claim 1, characterized in that: The central support rod is a hollow metal tube.

11. The high alloy pipeline welding root shielding gas support device according to claim 1, characterized in that: The movable connection adopts a pin connection mode.

12. The high alloy pipeline welding root shielding gas support device according to claim 1, characterized in that: A "V"-shaped structure is formed between adjacent directional movable support rods.

13. The high alloy pipeline welding root shielding gas support device according to claim 1, characterized in that: A "V"-shaped structure is formed between adjacent hydraulic support rods.

14. The high alloy pipeline welding root shielding gas support device according to claim 1, characterized in that: The central support rod is a round straight rod.

15. The high alloy pipeline welding root shielding gas support device according to claim 14, characterized in that: The central support rod is a steel pipe or an aluminum alloy pipe.

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