Pipeline welding inner wall anti-oxidation gas protection device and using method

Abstract

The invention provides a pipeline welding inner wall anti-oxidation gas protection device and a using method, and the pipeline welding inner wall anti-oxidation gas protection device comprises two sealing assemblies which are connected through an adjusting solenoid. Each sealing assembly comprises an outer sleeve, a jacking mechanism and a sealing gasket fixing plate. One end of the outer sleeve is closed and is connected with the screw rod, and the other end of the outer sleeve is opened and provided with a bent ring; right-hand and left-hand threads are arranged on two sides of the adjusting screw tube for adjusting the distance between the sealing assemblies. The jacking mechanism drives a jacking rod to support the inner wall of the pipeline through argon, and a piston rod controls expansion and contraction of a sealing rubber pad. The sealing performance of the protection area can be ensured, the situation that the inner wall is oxidized in the welding process is avoided, it is ensured that the inner wall of the pipeline is protected against oxidation in the welding process, and argon consumption can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of argon arc welding equipment, and in particular to an anti-oxidation gas protection device for inner wall of pipeline welding and a use method thereof. Background Art

[0002] Titanium alloy pipes are increasingly used in corrosion protection, especially in environments involving strong acids. The quality of pipe welding plays a crucial role in the service life of the pipe. During pipe welding, oxidation of the inner wall is a common problem, especially when using argon arc welding. The temperature in the weld area can rise rapidly, reaching locally over 5,000 degrees Celsius. Since welding is performed from the outside of the pipe, in addition to the gas shielding provided by the argon arc welding torch, protective devices such as drag shields are currently used to protect and cool the weld after welding. Argon gas is passed through the pipe to replace the internal air to achieve the purpose of protecting the inner wall.

[0003] Although current technology already uses argon gas for welding protection, for large-diameter pipes (e.g., DN100 and above) or long pipes (e.g., over 5 meters), the amount of argon gas introduced into the pipe is very large, and it is difficult to completely replace the internal air. This often leads to oxidation of the inner wall, reducing weld quality and pipe life. Therefore, how to effectively protect the interior of the pipe during welding, improve weld quality, reduce argon usage, and lower costs are currently unresolved issues. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti-oxidation gas protection device for the inner wall of pipeline welding and a method of use, which can improve welding quality while reducing the use of argon gas, lowering costs, and effectively preventing oxidation of the inner wall.

[0005] According to one object of the present invention, the present invention provides an anti-oxidation gas protection device for the inner wall of a pipeline weld, comprising two sealing assemblies of identical structure, the two sealing assemblies being connected by an adjusting spiral tube;

[0006] Each of the sealing assemblies comprises an outer sleeve, a tightening mechanism and a sealing gasket fixing plate; one end of the outer sleeve is closed and fixedly connected to the screw, the other end of the outer sleeve is open and provided with a bent ring, a perforated partition plate, a piston and a piston spring are provided inside the outer sleeve, the piston is connected to the hollow piston rod, and the piston spring is sleeved on the hollow piston rod;

[0007] The adjusting solenoid is provided with positive and negative threads on both sides, which are respectively connected to the connecting screws on the two sealing assemblies through threads, and are used to adjust the distance between the two sealing assemblies to set the protection area range;

[0008] The tightening mechanism includes a plurality of push rods arranged along the circumference of the outer sleeve, and the push rods are driven by argon gas to tighten the inner wall of the pipe;

[0009] The hollow piston rod passes through the curved ring and is connected to the sealing gasket fixing plate. A sealing rubber gasket is fixed on the sealing gasket fixing plate. The hollow piston rod is connected to an argon hose, and the expansion and contraction of the sealing rubber gasket is controlled by the argon pressure.

[0010] Furthermore, the number of the tightening mechanisms is three, and the three tightening mechanisms are evenly distributed in the circumferential direction of the outer sleeve.

[0011] Furthermore, the tightening mechanism includes a push rod sleeve and a push rod spring. The push rod is sleeved on the side wall of the outer sleeve and connected to the interior; the push rod moves through the push rod sleeve, and a push rod piston is provided at the bottom of the push rod. The push rod spring is located in the push rod sleeve and sleeved on the outside of the push rod. The push rod is driven out by argon pressure to tighten the inner wall of the pipe, and is reset under the action of the spring.

[0012] Furthermore, an air hole is provided on the side wall of the outer sleeve, and the air hole is located between the perforated partition and the closed end of the outer sleeve. When the piston moves to the position of the air hole, argon gas enters the protection area through the air hole.

[0013] Furthermore, the hollow piston rod is connected to the argon hose through a thread, and the argon gas enters the interior of the outer sleeve through the hollow piston rod, passes through the perforated partition and the air hole in turn, enters the protection area, drives the hollow piston rod to move outward and discharges the air in the protection area.

[0014] Furthermore, the sealing rubber pad is fixed on the sealing pad fixing plate, and is brought into contact with or out of contact with the inner wall of the pipe through the axial movement of the hollow piston rod. An exhaust hole is provided on the sealing pad fixing plate.

[0015] According to another object of the present invention, the present invention provides a method for using the above-mentioned pipeline welding inner wall anti-oxidation gas protection device, comprising the following steps:

[0016] Select a sealing assembly that matches the diameter of the pipe to be welded, and insert the two sealing assemblies into the two sections of the pipe to be welded respectively;

[0017] Adjust the distance between the two sealing components by adjusting the screw tube so that the protection area covers the welding position;

[0018] Connect the argon hose to the hollow piston rod, open the argon bottle and adjust the pressure;

[0019] Argon gas drives the push rod to extend to form a three-point support to fix the inner wall of the pipe, and at the same time drives the sealing rubber pad to expand the sealing protection area;

[0020] During welding, argon gas is continuously introduced to replace the air in the protection area;

[0021] After welding is completed, the gas supply is stopped, the ejector rod and the sealing rubber pad are reset under the action of the spring, and the device is withdrawn.

[0022] Furthermore, the argon pressure is adjusted by a pressure reducing valve to drive the ejector rod and the piston rod to move synchronously.

[0023] Furthermore, when the argon gas enters the protection area, it is evenly diffused through the perforated partition plate and the pores, and the residual air is discharged through the exhaust holes of the sealing gasket fixing plate.

[0024] Furthermore, after welding is completed, the sealing assembly is pulled out from one end of the pipeline through the connecting hose to complete the welding and protection process.

[0025] The technical solution of the present invention can provide argon gas to the protective device through a hose that conveys argon gas. The argon gas drives the push rod and the hollow piston rod to move respectively through the hollow piston rod and the partition with holes. The push rod is driven to extend by air pressure to tightly support the inner wall of the pipeline. The movement of the hollow piston rod controls the expansion or contraction of the sealing rubber pad to ensure the sealing of the protection area, avoid the oxidation of the inner wall during welding, ensure that the inner wall of the pipeline is protected from oxidation during welding, and effectively reduce the consumption of argon gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a schematic diagram of the structure of the initial state of an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of the working state of an embodiment of the present invention;

[0029] Figure 3 This is a structural diagram of a sealing gasket fixing plate according to an embodiment of the present invention;

[0030] Figure 4 This is a schematic structural diagram of an adjusting solenoid according to an embodiment of the present invention;

[0031] Figure 5 This is a schematic structural diagram of an end cover according to an embodiment of the present invention;

[0032] Figure 6 This is a schematic structural diagram of a push rod according to an embodiment of the present invention;

[0033] Figure 7 This is a schematic structural diagram of an outer sleeve according to an embodiment of the present invention;

[0034] Figure 8 This is a schematic structural diagram of a bent ring according to an embodiment of the present invention;

[0035] Figure 9 Schematic diagram of the structure of the piston and hollow piston rod according to an embodiment of the present invention;

[0036] In the figure, 1. outer sleeve; 2. connecting screw; 3. adjusting screw; 4. perforated partition; 5. piston; 6. hollow piston rod; 7. bent ring; 8. piston spring; 9. sealing gasket fixing plate; 10. sealing rubber gasket; 11. argon hose; 12. pipe joint; 13. push rod sleeve; 14. push rod; 15. push rod piston; 16. air hole; 17. argon cylinder; 18. pressure reducing valve; 19. exhaust hole; 20. end cover. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0040] Example 1

[0041] like Figure 1-9 As shown,

[0042] A device for protecting the inner wall of a pipeline from oxidation gas is disclosed, comprising two sealing components with identical structures, namely a first component and a second component. The first component and the second component are connected by an adjusting screw 3, which is connected to the first component and the second component respectively by positive and negative threads for adjusting the range of the protection area.

[0043] Specifically, the two sealing assemblies each include an outer sleeve 1, which is closed on one side and open on the other. A connecting screw 2 is fixed to the closed end of the outer sleeve 1, and the outer side of the connecting screw 2 is provided with an external thread, and the two sides of the adjustment screw 3 are provided with internal threads with positive and negative threads. When in use, the two sealing assemblies are arranged in a direction away from each other, and the connecting screws 2 of the two sealing assemblies are respectively arranged in a corresponding manner and connected by the adjustment screw 3. The adjustment screw 3 is threadedly connected to the connecting screws 2 of the two sealing assemblies, and the distance between the two outer sleeves 1 is adjusted by the positive and negative threads.

[0044] A perforated partition 4 is fixed to the inner side of the outer sleeve 1 near the closed end, and an end cover 20 and a bent ring 7 are fixed to the open end of the outer sleeve 1. The end cover 20 is threadedly connected to the open end of the outer sleeve 1, and the bent ring 7 is fixedly connected to the end cover 20 by screws. A piston 5 and a hollow piston rod 6 are provided inside the outer sleeve 1, and a piston spring 8 is provided between the piston 5 and the bent ring 7. The piston spring 8 is sleeved on the hollow piston rod 6, and one end of the hollow piston rod 6 extending out of the bent ring 7 is threadedly connected to a sealing gasket fixing plate 9, and a sealing rubber gasket 10 is fixed on the sealing gasket fixing plate 9.

[0045] The hollow piston rod 6 is a hollow piston rod 6 , and one end of the hollow piston rod 6 located outside the bent ring 7 is provided with a pipe joint 12 for connecting to an argon hose 11 .

[0046] Three tightening mechanisms are provided on the side wall of the outer sleeve 1 near the closed end. The three tightening mechanisms are evenly distributed 120 degrees in the circumferential direction of the outer sleeve 1. The tightening mechanisms are located between the perforated partition plate 4 and the closed bottom wall of the outer sleeve 1. Specifically, the tightening mechanism includes a push rod sleeve 13 and a push rod 14 provided on the side wall of the outer sleeve 1. The bottom of the push rod sleeve 13 is connected to the interior of the outer sleeve 1. The push rod 14 passes through the push rod sleeve 13 and is movably provided within the push rod sleeve 13. A push rod piston 15 is provided at the bottom of the push rod 14 and is provided between the push rod piston 15 and the top inner wall of the push rod sleeve 13.

[0047] An air hole 16 is further provided on the side wall of the outer sleeve 1 , and the air hole 16 is arranged at a certain position between the perforated partition plate 4 and the middle position of the outer sleeve 1 .

[0048] In this embodiment, both sealing assemblies are internally equipped with a hollow piston rod 6 and a perforated partition 4. Under the action of argon gas, the hollow piston rod 6 drives a sealing gasket retaining plate 9, thereby controlling the contraction or expansion of a sealing rubber pad 10 on the sealing gasket retaining plate 9, thereby achieving internal sealing of the pipe to be welded. Furthermore, the argon gas drives the extension and contraction of ejector pins 14, which are evenly distributed across both sealing assemblies and arranged 120 degrees on their housings. Driven by gas pressure, they extend to overcome the ejector pin spring force, forming a three-point support structure that secures the inner wall of the pipe.

[0049] In this embodiment, the protective device is connected to an argon cylinder 17 via an argon hose 11, facilitating the delivery and regulation of argon gas. Argon gas originates from the argon cylinder 17, which is connected to the argon hose 11. This hose is equipped with a pressure reducing valve 18 and an on / off valve. The argon hose 11 is connected to the pipe joint 12 at the end of the hollow piston rod 6. After the argon gas passes through the pressure-regulating valve 18, it enters the first and second components and is expelled from the protected area through the perforated partition 4.

[0050] During welding, the protection device effectively prevents oxidation of the inner wall of the pipe by passing argon gas into the protection area. After welding is completed, the argon gas is stopped and the ejector rod and the hollow piston rod 6 are reset under the action of the spring force.

[0051] This embodiment of the protection device is suitable for pipes with a diameter of DN100 or greater or a length greater than 5 meters, effectively reducing argon gas usage and improving welding quality. The structural design of the protection device ensures that the device can be easily removed from the pipe after welding is completed, facilitating subsequent operation and cleaning.

[0052] Example 2

[0053] The structure of this embodiment is substantially the same as that of the above embodiment, except that, in this embodiment, the protection device, when used, includes the following steps:

[0054] Device preparation:

[0055] Select a protective device that fits the inner diameter of the pipe. The protective device includes two identical sealing components, namely a first component and a second component, which are connected by an adjustment screw 3. The adjustment screw 3 is connected to the first component and the second component respectively through positive and negative threads to adjust the range of the protection area.

[0056] Argon connection:

[0057] Passing an argon gas delivery hose through the pipe to be welded and connecting the hose to the first component and the second component respectively;

[0058] The adjusting screw 3 is adjusted, the first component and the second component are respectively inserted into two sections of the pipe to be welded, and the appropriate protection area range is set by adjusting the screw 3.

[0059] To enable protection:

[0060] After adjusting the installation positions of the first component and the second component, open the argon cylinder, and the argon gas enters the first component and the second component respectively after the pressure is adjusted by the pressure reducing valve;

[0061] Drive unit:

[0062] After the argon gas enters the first component and the second component, it passes through the hollow piston rod 6 and the perforated partition plate, driving the hollow piston rod 6 and the push rod to move.

[0063] Three evenly spaced push rods are provided on the outer shells of the first and second components, respectively. The push rods are evenly spaced at 120-degree angles on the outer shells of the first and second components. Driven by air pressure, the push rods overcome the push rod spring force and extend to form a three-point support, tightly pressing against the inner wall of the pipe, fixing the first and second components respectively, and ensuring effective protection of the sealing area.

[0064] As argon gas is continuously introduced, the piston moves outward under the driving force of air pressure, driving the hollow piston rod 6 outward to a certain extent and compressing the piston spring 8. The sealing gasket fixing plate 9 fixed at one end of the hollow piston rod 6 moves outward, and the sealing rubber gasket 10 on the sealing gasket fixing plate 9 comes out of the bent ring 7, contacts the inner wall of the pipe to be welded, and seals the protection area; at the same time, when the piston running position passes through the air hole on the outer sleeve 1, argon gas enters the protection area through the air hole, and the air in the protection area is discharged through the exhaust hole 19 on the sealing gasket fixing plate 9.

[0065] Welding and gas shielding:

[0066] During the welding process, normal argon shielded welding is used on the outside of the pipe to be welded, and argon is continuously introduced into the inside of the pipe to be welded. The argon shielding gas enters the protection area to protect the high-temperature area of ​​the inner wall of the pipe to be welded, ensuring that the inner wall of the pipe will not be oxidized during the welding process.

[0067] After welding is completed, when the pipeline temperature drops below the material oxidation temperature, the argon gas flow is stopped. At this time, the push rod and the hollow piston rod 6 are reset under the action of the spring, and the sealing gasket fixing plate 9 moves inward with the hollow piston rod 6. The sealing rubber gasket 10 returns to the bent ring 7 under the action of external force, breaks away from the contact with the inner wall of the pipeline, and releases the seal.

[0068] Device Evacuation:

[0069] After welding is completed, the protective device is pulled out from one end of the pipe through the connecting hose to complete the entire welding and protection process.

[0070] When the protective device of the present invention is in use, argon gas can be provided to the protective device through a hose for conveying argon gas. The argon gas drives the push rod and the hollow piston rod 6 to move respectively through the hollow piston rod 6 and the perforated partition. The push rod is driven to extend by air pressure to tightly support the inner wall of the pipeline. The movement of the hollow piston rod 6 controls the expansion or contraction of the sealing rubber pad 10 to ensure the sealing of the protection area, avoid the oxidation of the inner wall during welding, ensure that the inner wall of the pipeline is protected from oxidation during welding, and can effectively reduce the consumption of argon gas.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pipeline welding inner wall anti-oxidation gas protection device, characterized in that: It comprises two sealing assemblies with the same structure, and the two sealing assemblies are connected by an adjusting spiral tube; Each of the sealing assemblies comprises an outer sleeve, a tightening mechanism and a sealing gasket fixing plate; one end of the outer sleeve is closed and fixedly connected to the screw, the other end of the outer sleeve is open and provided with a bent ring, a perforated partition plate, a piston and a piston spring are provided inside the outer sleeve, the piston is connected to the hollow piston rod, and the piston spring is sleeved on the hollow piston rod; The adjusting solenoid is provided with positive and negative threads on both sides, which are respectively connected to the connecting screws on the two sealing assemblies through threads, and are used to adjust the distance between the two sealing assemblies to set the protection area range; The tightening mechanism includes a plurality of push rods arranged along the circumference of the outer sleeve, and the push rods are driven by argon gas to tighten the inner wall of the pipe; The hollow piston rod passes through the curved ring and is connected to the sealing gasket fixing plate. A sealing rubber gasket is fixed on the sealing gasket fixing plate. The hollow piston rod is connected to an argon hose, and the expansion and contraction of the sealing rubber gasket is controlled by the argon pressure.

2. The anti-oxidation gas protection device for inner wall of pipeline welding according to claim 1 is characterized in that: There are three tightening mechanisms, and the three tightening mechanisms are evenly distributed in the circumferential direction of the outer sleeve.

3. The anti-oxidation gas protection device for inner wall of pipeline welding according to claim 1, characterized in that: The tightening mechanism includes a push rod sleeve and a push rod spring. The push rod is sleeved on the side wall of the outer sleeve and connected to the interior. The push rod moves through the push rod sleeve. A push rod piston is provided at the bottom of the push rod. The push rod spring is located in the push rod sleeve and sleeved on the outside of the push rod. The push rod is driven out by argon pressure to tighten the inner wall of the pipe and is reset under the action of the spring.

4. The anti-oxidation gas protection device for inner wall of pipeline welding according to claim 1, characterized in that: The side wall of the outer sleeve is provided with an air hole, and the air hole is located between the perforated partition and the closed end of the outer sleeve. When the piston moves to the position of the air hole, argon gas enters the protection area through the air hole.

5. The anti-oxidation gas protection device for inner wall of pipeline welding according to claim 4, characterized in that: The hollow piston rod is connected to the argon hose through a thread, and the argon gas enters the interior of the outer sleeve through the hollow piston rod, passes through the perforated partition and the air hole in sequence, enters the protection area, drives the hollow piston rod to move outward and discharges the air in the protection area.

6. The anti-oxidation gas protection device for inner wall of pipeline welding according to claim 1, characterized in that: The sealing rubber pad is fixed on the sealing pad fixing plate, and is brought into contact with or separated from the inner wall of the pipeline by the axial movement of the hollow piston rod. An exhaust hole is provided on the sealing pad fixing plate.

7. The method for using the anti-oxidation gas protection device for inner wall of pipeline welding according to any one of claims 1 to 6, characterized in that: The following steps are involved: Select a sealing assembly that matches the diameter of the pipe to be welded, and insert the two sealing assemblies into the two sections of the pipe to be welded respectively; Adjust the distance between the two sealing components by adjusting the screw tube so that the protection area covers the welding position; Connect the argon hose to the hollow piston rod, open the argon bottle and adjust the pressure; Argon gas drives the push rod to extend to form a three-point support to fix the inner wall of the pipe, and at the same time drives the sealing rubber pad to expand the sealing protection area; During welding, argon gas is continuously introduced to replace the air in the protection area; After welding is completed, the gas supply is stopped, the ejector rod and the sealing rubber pad are reset under the action of the spring, and the device is withdrawn.

8. The method for using the anti-oxidation gas protection device for the inner wall of pipeline welding according to claim 7, characterized in that: The argon pressure is adjusted by a pressure reducing valve to drive the ejector rod and the piston rod to move synchronously.

9. The method for using the anti-oxidation gas protection device for the inner wall of pipeline welding according to claim 7, characterized in that: When the argon gas enters the protection area, it is evenly diffused through the perforated partition plate and the air holes, and the residual air is discharged through the exhaust holes of the sealing gasket fixing plate.

10. The method for using the anti-oxidation gas protection device for inner wall of pipeline welding according to claim 7, characterized in that: After welding is completed, the sealing assembly is pulled out from one end of the pipe through the connecting hose to complete the welding and protection process.

Images