Arc striking device of longitudinal submerged arc welding steel pipe

Abstract

The invention discloses an arc striking device for longitudinal submerged arc welding of a steel pipe, and belongs to the field of steel pipe welding processes, the arc striking device comprises a pipe to be welded and an arc striking pipe, the pipe to be welded and the arc striking pipe are jointly and movably provided with an installation block, and the installation block is provided with a fixing assembly; the fixing assembly comprises a threaded rod rotationally installed on the installation block, and a linkage block is installed on the threaded rod in a threaded mode. According to the scheme, a fixing plate is arranged, a to-be-welded pipe and an arc striking pipe can be fixed through the fixing plate before arc striking, meanwhile, a spring telescopic rod is driven to move through a push rod in the moving process of an extrusion plate, and after the fixing plate is attached to the inner wall of the arc striking pipe, the output end of the spring telescopic rod makes contact with a fixing groove; at the moment, the output end of the spring telescopic rod extends and is inserted into the fixing groove, the piston plate is fixed, namely, the fixing plate is fixed and cannot move, so that the situation that the fixing plate moves in the arc striking process, the arc striking tube deviates, and the arc striking effect is affected is avoided, and the effect of improving the arc striking effect is achieved.

Description

Technical Field

[0001] The invention relates to the field of steel pipe welding technology, and more specifically to an arc starting device for straight seam submerged arc welding of steel pipes. Background Art

[0002] During the submerged arc welding process, many weld quality problems are caused by unstable current in the arc starting stage. Therefore, in order to ensure the welding quality, it is hoped that the weld will not be on the workpiece before the welding arc is stable. A weld arc starting plate should be set at the beginning of the welding joint before welding.

[0003] The existing arc-starting device for straight seam submerged arc welding generally spot-welds two metal plates to one end of the weld to be welded before welding, and then starts to start the arc from the two metal plates. When the welding arc moves to the weld to be processed, the welding current, voltage and welding arc are relatively stable. At this time, the weld quality is relatively good. After the welding is completed, the arc-starting plate is cut off. However, since the surface of the steel pipe is arc-shaped and difficult to fix, and the traditional arc-starting plate does not have a special positioning device to position it at both ends of the steel pipe, it cannot be completely level with the steel pipe, causing the worker to use the welding gun to cause a certain angle between the arc-starting plate and the steel pipe. During submerged arc welding, the slag will flow in front of the arc to cause slag inclusion, which seriously affects the weld quality at both ends of the steel pipe.

[0004] In view of the above problems, some solutions are also provided in the prior art. For example, the Chinese utility model patent with announcement number CN216227464U discloses a device for effectively extending the length of the weld at the end of a steel pipe. The device is provided with a level sensor at both the end of the steel pipe and the end of the arc-starting plate clamp, and a signal light is provided on the device. By means of bolt fine-tuning, the signal light automatically lights up after the arc-starting plate and the steel pipe are kept level, thereby reducing the measurement time, improving work efficiency, and ensuring the quality of the weld. Although the prior art can improve the quality of the weld to a certain extent, the prior art is relatively cumbersome and requires rotating the bolts back and forth for adjustment, thereby reducing the work efficiency to a certain extent. In addition, the prior art is simply fixed by threads. When the bolts are not fully rotated into place, the arc-starting plate is easily offset, thereby seriously affecting the arc-starting effect. Summary of the invention

[0005] In view of the problems existing in the prior art, the object of the present invention is to provide an arc striking device for a straight seam submerged arc welded steel pipe, which can achieve the purpose of improving the arc striking effect.

[0006] To solve the above problems, the present invention adopts the following technical solutions.

[0007] An arc-starting device for a straight seam submerged arc welded steel pipe comprises a pipe to be welded and an arc-starting pipe, wherein a mounting block is movably mounted on the pipe to be welded and the arc-starting pipe, and a fixing component is arranged on the mounting block;

[0008] The fixing assembly includes a threaded rod rotatably mounted on a mounting block, a linkage block is threadedly mounted on the threaded rod, a telescopic tube is commonly mounted between the linkage block and the mounting block, a sleeve is fixedly mounted on both the linkage block and the mounting block, a piston plate is slidably mounted in the sleeve, a first spring is commonly fixedly mounted between the piston plate and the sleeve, a mounting rod is fixedly mounted on the piston plate, a fixing plate is fixedly mounted on one end of the mounting rod away from the piston plate, an electromagnet is embedded in the mounting block, a second spring is fixedly mounted on the side wall of the sleeve, an extrusion plate is fixedly mounted on one end of the second spring away from the sleeve, a magnet block is embedded in the extrusion plate, and a locking assembly cooperating with the extrusion plate is provided on the piston plate.

[0009] Furthermore, the locking assembly includes an installation groove provided on the piston plate, a spring telescopic rod is slidably installed in the installation groove, a third spring is fixedly installed between the spring telescopic rod and the installation groove, a fixing groove matching with the output end of the spring telescopic rod is provided on the side wall of the sleeve, and the end of the spring telescopic rod away from the fixing groove is an inclined surface, a sliding groove is provided on the piston plate, a push rod is slidably installed in the sliding groove, and a return spring is fixedly installed between the push rod and the sliding groove.

[0010] Furthermore, a fixed cavity is provided on the fixed plate, air holes are evenly provided on the fixed cavity, a first air pipe is inserted on the fixed cavity, a sealing rod is slidably installed on the piston plate, a fourth spring is commonly installed between the sealing rod and the piston plate, and a connecting groove connected to the first air pipe is provided on the sealing rod.

[0011] Furthermore, a second air pipe communicating with the fixing cavity is inserted on the mounting rod.

[0012] Furthermore, an arc-striking groove is provided on the arc-striking tube, a vertical groove is provided on the mounting block, a limit plate cooperating with the arc-striking groove is slidably installed in the vertical groove, and a third air pipe connected with the telescopic tube is inserted in the vertical groove.

[0013] Furthermore, an exhaust valve whose output end is connected to the outside is fixedly mounted on the sleeve.

[0014] Furthermore, the output end of the spring telescopic rod is a conical surface.

[0015] Furthermore, the bottom wall of the push rod is a smooth mirror surface.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) In this scheme, by setting a fixing plate, the welding pipe and the arc-starting tube can be fixed by the fixing plate before arc-starting. At the same time, during the movement of the extrusion plate, the spring telescopic rod is driven to move by the push rod and after the fixing plate and the inner wall of the arc-starting tube are fitted, the output end of the spring telescopic rod contacts the fixing groove. At this time, the output end of the spring telescopic rod is extended and inserted into the fixing groove. At this time, the piston plate is fixed, that is, the fixing plate is fixed and cannot move, thereby avoiding the movement of the fixing plate during the arc-starting process, causing the arc-starting tube to deviate and affect the arc-starting effect, thereby improving the arc-starting effect;

[0018] (2) This scheme opens a fixed cavity. During the process of the piston plate moving and compressing the first spring, the pressure in the space on the side of the piston plate near the extrusion plate in the sleeve is reduced. Then, the piston plate drives the sealing rod to move during the movement, and the sealing rod gradually contacts the sleeve during the movement. Then, the sleeve drives the sealing rod to squeeze the fourth spring. After the fixed plate fits the inner wall of the arc-starting tube, the sealing rod drives the connecting groove to connect with the first air pipe. At this time, under the action of pressure, the space on the side of the piston plate near the extrusion plate in the sleeve sucks air from the fixed cavity through the connecting groove and the first air pipe, and makes the fixed cavity negatively pressurized. At this time, the fixed cavity tends to suck air through the air holes. Since the fixed plate fits the inner wall of the arc-starting tube at this time, the fixed plate and the arc-starting tube are tightly sucked together under the action of pressure, thereby preventing the arc-starting tube from rotating, causing the arc-starting tube and the pipe to be welded to deviate, and further improving the arc-starting effect.

[0019] (3) In this scheme, a second air pipe is provided. When the piston plate drives the fixed plate to clamp the arc-striking tube through the mounting rod, the piston plate drives the air flow in the space on the side of the piston plate in the sleeve away from the extrusion plate to flow into the fixed cavity through the second air pipe, and blows toward the inner wall of the arc-striking tube through the air holes on the fixed cavity, thereby preventing dust from forming on the inner wall of the arc-striking tube and affecting the fitting effect between the arc-striking tube and the fixed plate.

[0020] (3) This scheme sets a limit plate so that the arc-striking groove on the arc-striking tube can fit with the limit plate before the arc-striking tube is fixed. Then, under the action of the limit plate, the arc-striking groove and the welding groove on the pipe to be welded can be aligned, thereby further improving the arc-striking effect. In the process of the threaded rod driving the linkage block to move toward the mounting block, the telescopic tube is compressed, and then the air flow in the telescopic tube flows into the vertical groove through the third air pipe, thereby increasing the pressure in the vertical groove. Then, under the action of the pressure, the limit plate moves into the vertical groove and gradually breaks away from the arc-striking groove, thereby avoiding affecting the normal development of the arc-striking work. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2It is a combined diagram of the mounting block, linkage block, sleeve, fixing plate and threaded rod of the present invention;

[0023] Figure 3 For the present invention Figure 2 Enlarged view of point A in the middle;

[0024] Figure 4 It is a cross-sectional view of the sleeve, piston plate, extrusion plate and mounting rod of the present invention;

[0025] Figure 5 For the present invention Figure 4 Enlarged view of point B in the middle;

[0026] Figure 6 For the present invention Figure 4 Enlarged view of point C in the middle;

[0027] Figure 7 It is a top cross-sectional view of the fixing plate and the mounting rod of the present invention;

[0028] Figure 8 It is a side sectional view of the limiting plate and the mounting block of the present invention.

[0029] Description of the numbers in the figure:

[0030] 1. Pipe to be welded; 2. Arc-starting pipe;

[0031] 3. Fixing assembly; 301. Threaded rod; 302. Linking block; 303. Telescopic tube; 304. Sleeve; 305. Piston plate; 306. First spring; 307. Mounting rod; 308. Fixing plate; 309. Electromagnet; 310. Second spring; 311. Extrusion plate; 312. Magnet block; 313. Mounting block;

[0032] 4. Locking assembly; 401. Spring telescopic rod; 402. Third spring; 403. Fixing slot; 404. Push rod; 405. Return spring;

[0033] 501, fixed cavity; 502, air hole; 503, first air pipe; 504, sealing rod; 505, fourth spring; 506, connecting groove;

[0034] 6. Second air pipe; 7. Arc striking groove; 8. Vertical groove; 9. Limit plate; 10. Third air pipe; 11. Exhaust valve. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention.

[0036] See also Figures 1 to 8 , an arc-starting device for straight seam submerged arc welding steel pipe, comprising a pipe to be welded 1 and an arc-starting tube 2, a mounting block 313 is movably mounted on the pipe to be welded 1 and the arc-starting tube 2, and a fixing component 3 is provided on the mounting block 313;

[0037] The fixing assembly 3 includes a threaded rod 301 rotatably mounted on a mounting block 313, a linkage block 302 is threadedly mounted on the threaded rod 301, a telescopic tube 303 is commonly installed between the linkage block 302 and the mounting block 313, a sleeve 304 is fixedly mounted on both the linkage block 302 and the mounting block 313, a piston plate 305 is slidably mounted in the sleeve 304, a first spring 306 is commonly fixedly mounted between the piston plate 305 and the sleeve 304, and the piston plate 304 is fixedly mounted on the sleeve 304. 5, a mounting rod 307 is fixedly mounted on the mounting rod 307, a fixing plate 308 is fixedly mounted on the end of the mounting rod 307 away from the piston plate 305, an electromagnet 309 is embedded in the mounting block 313, a second spring 310 is fixedly mounted on the side wall of the sleeve 304, an extrusion plate 311 is fixedly mounted on the end of the second spring 310 away from the sleeve 304, a magnet block 312 is embedded in the extrusion plate 311, and a locking assembly 4 cooperating with the extrusion plate 311 is provided on the piston plate 305.

[0038] The locking assembly 4 includes a mounting groove provided on the piston plate 305, a spring telescopic rod 401 is slidably installed in the mounting groove, a third spring 402 is fixedly installed between the spring telescopic rod 401 and the mounting groove, a fixing groove 403 cooperating with the output end of the spring telescopic rod 401 is provided on the side wall of the sleeve 304, and the end of the spring telescopic rod 401 away from the fixing groove 403 is an inclined surface, a sliding groove is provided on the piston plate 305, a push rod 404 is slidably installed in the sliding groove, and a return spring 405 is fixedly installed between the push rod 404 and the sliding groove.

[0039] When in use, the pipe to be welded 1 is aligned with the arc-starting tube 2, and then the bottom wall of the mounting plate is aligned with the pipe to be welded 1 and the arc-starting tube 2, and then the electromagnet 309 is energized, at which time the electromagnet 309 generates an electromagnetic field, and then under the action of the electromagnetic field, the magnet block 312 moves in a direction away from the electromagnet 309, and in the process of the movement of the magnet block 312, the squeezing plate 311 is driven to move and stretch the second spring 310, and in the process of the movement of the squeezing plate 311, the piston plate 305 is driven to move and compress the first spring 306, and then in the process of the movement of the piston plate 305, the fixing plate 308 is driven by the mounting rod 307 to fix the inner walls of the pipe to be welded 1 and the arc-starting tube 2 respectively, at which time the positions of the pipe to be welded 1 and the arc-starting tube 2 are fixed, and then the user The threaded rod 301 can be rotated. Since the threaded rod 301 is threadedly connected to the connecting block 302, and the connecting block 302 cannot be rotated under the action of the telescopic tube 303, the connecting block 302 is driven to approach the mounting block 313 during the rotation of the threaded rod 301. During the movement of the connecting block 302, the arc-starting tube 2 is driven to approach the pipe to be welded 1 through the sleeve 304, the mounting rod 307, and the fixing plate 308, and gradually makes the arc-starting tube 2 fit the pipe to be welded 1, so that the user does not need to spend time turning the bolts multiple times to fix the arc-starting tube 2 on the pipe to be welded 1, thereby improving work efficiency. At the same time, it can also avoid arc-starting deviation caused by the bolts not being rotated into place, thereby improving the arc-starting effect.

[0040] In the process of the squeezing plate 311 stretching the second spring 310, the squeezing plate 311 gradually contacts the push rod 404 and drives the push rod 404 to move along the slide groove. At this time, the reset spring 405 is compressed and has a tendency to recover. In the process of the push rod 404 moving, it gradually contacts the inclined surface of the spring telescopic rod 401 and applies a thrust to the inclined surface of the spring telescopic rod 401. Then, the spring telescopic rod 401 is driven to move under the action of the thrust. At this time, the third spring 402 is compressed and has a tendency to recover. At the same time, in the process of the spring telescopic rod 401 moving, the spring telescopic rod 40 1 contracts and has a tendency to recover, and then drives the spring telescopic rod 401 to move during the movement of the piston plate 305, and after the fixed plate 308 fits the inner wall of the arc-striking tube 2, the output end of the spring telescopic rod 401 contacts the fixed groove 403, and the output end of the spring telescopic rod 401 stretches and inserts into the fixed groove 403. At this time, the piston plate 305 is fixed, that is, the fixed plate 308 is fixed and cannot move, thereby avoiding the fixed plate 308 from moving during the arc-striking process, causing the arc-striking tube 2 to deviate and affect the arc-striking effect, and further improving the arc-striking effect.

[0041] like Figure 4 , Figure 5 , Figure 7As shown, a fixed cavity 501 is provided on the fixed plate 308, air holes 502 are evenly provided on the fixed cavity 501, a first air pipe 503 is inserted into the fixed cavity 501, a sealing rod 504 is slidably installed on the piston plate 305, a fourth spring 505 is installed between the sealing rod 504 and the piston plate 305, and a connecting groove 506 connected to the first air pipe 503 is provided on the sealing rod 504.

[0042] A second air pipe 6 communicating with the fixing cavity 501 is inserted on the mounting rod 307 .

[0043] By adopting the above technical solution, during the process of the piston plate 305 moving and compressing the first spring 306, the pressure in the space on the side of the piston plate 305 close to the extrusion plate 311 in the sleeve 304 is reduced, and then the sealing rod 504 is driven to move during the movement of the piston plate 305, and the sealing rod 504 gradually contacts the sleeve 304 during the movement, and then the sleeve 304 drives the sealing rod 504 to squeeze the fourth spring 505, and after the fixing plate 308 is attached to the inner wall of the arc-starting tube 2, the sealing rod 504 drives the connecting groove 506 to connect with the first air pipe 503. At this time, under the action of pressure, the space on the side of the piston plate 305 close to the extrusion plate 311 in the sleeve 304 sucks air from the fixed cavity 501 through the connecting groove 506 and the first air pipe 503, and makes the fixed cavity 501 have a negative pressure. At this time, the fixed cavity 501 tends to suck air through the air hole 502. Since the fixed plate 308 fits the inner wall of the arc-striking tube 2 at this time, the fixed plate 308 and the arc-striking tube 2 are tightly sucked together under the action of pressure, thereby preventing the arc-striking tube 2 from rotating, causing the arc-striking tube 2 to deviate from the pipe 1 to be welded, and further improving the arc-striking effect.

[0044] When the piston plate 305 drives the fixed plate 308 to clamp the arc-striking tube 2 through the mounting rod 307, the piston plate 305 drives the air flow in the space on the side of the piston plate 305 in the sleeve 304 away from the extrusion plate 311 to flow into the fixed cavity 501 through the second air pipe 6, and blows toward the inner wall of the arc-striking tube 2 through the air hole 502 on the fixed cavity 501, thereby preventing dust from forming on the inner wall of the arc-striking tube 2 and affecting the fitting effect between the arc-striking tube 2 and the fixed plate 308.

[0045] like Figure 3 , Figure 8 As shown, the arc-striking groove 7 is provided on the arc-striking tube 2, the mounting block 313 is provided with a vertical groove 8, a limiting plate 9 cooperating with the arc-striking groove 7 is slidably installed in the vertical groove 8, and a third air pipe 10 connected with the telescopic tube 303 is inserted in the vertical groove 8.

[0046] By adopting the above technical scheme, before fixing the arc-striking tube 2, the arc-striking groove 7 on the arc-striking tube 2 can be fitted with the limiting plate 9, and then the arc-striking groove 7 can be aligned with the welding groove on the pipe to be welded 1 under the action of the limiting plate 9, thereby further improving the arc-striking effect, and in the process of the threaded rod 301 driving the linkage block 302 to move toward the mounting block 313, the telescopic tube 303 is compressed, and then the airflow in the telescopic tube 303 flows into the vertical groove 8 through the third air pipe 10, and the pressure in the vertical groove 8 is increased, and then the limiting plate 9 moves into the vertical groove 8 under the action of the pressure, and gradually breaks away from the arc-striking groove 7, thereby avoiding affecting the normal development of the arc-striking work.

[0047] like Figure 4 As shown, the sleeve 304 is fixedly mounted with an exhaust valve 11 whose output end is connected to the outside.

[0048] By adopting the above technical solution, after the arc is struck, the user can first turn off the power of the electromagnet 309, at which time the second spring 310 drives the extrusion plate 311 to reset, and gradually disengages from the push rod 404 during the resetting process of the extrusion plate 311, at which time the reset spring 405 drives the push rod 404 to reset and disengage from the spring telescopic rod 401, and then the third spring 402 drives the spring telescopic rod 401 to reset and disengage from the fixed groove 403, at which time the first spring 306 stretches and drives the piston plate 305 to reset, and during the resetting process of the piston plate 305, the fixing plate 308 is driven by the mounting rod 307. Reset. At this time, the user can take out the fixing component 3. At the same time, during the resetting process of the piston plate 305, the fourth spring 505 drives the sealing rod 504 to reset, and makes the connecting groove 506 disengage from the first air pipe 503. During the resetting process of the piston plate 305, the space in the sleeve 304 on the side of the piston plate 305 away from the extrusion plate 311 is inhaled through the second air pipe 6, the fixing cavity 501, and the air hole 502. At the same time, the gas in the space in the sleeve 304 on the side of the piston plate 305 close to the extrusion plate 311 flows to the outside through the exhaust valve 11, thereby preparing for work again.

[0049] like Figure 6 As shown, the output end of the spring telescopic rod 401 is a cone.

[0050] By adopting the above technical solution, during the process of the output end of the spring telescopic rod 401 extending and inserting into the fixed groove 403, the output end of the spring telescopic rod 401 is made into a conical surface, so that the initial contact area between the output end of the spring telescopic rod 401 and the fixed groove 403 can be reduced, thereby facilitating the output end of the spring telescopic rod 401 to be inserted into the fixed groove 403.

[0051] like Figure 6 As shown, the bottom wall of the push rod 404 is a smooth mirror surface.

[0052] By adopting the above technical solution, when the push rod 404 drives the spring telescopic rod 401 to move, the bottom wall of the push rod 404 will rub against the inclined surface of the spring telescopic rod 401. By making the bottom wall of the push rod 404 an inclined surface, the friction between the push rod 404 and the inclined surface of the spring telescopic rod 401 can be reduced, thereby ensuring that the push rod 404 drives the spring telescopic rod 401 to move normally.

[0053] Instructions for use: When in use, the pipe to be welded 1 is aligned with the arc-starting tube 2, and then the bottom wall of the mounting plate is aligned with the pipe to be welded 1 and the arc-starting tube 2, and then the electromagnet 309 is energized, at which time the electromagnet 309 generates an electromagnetic field, and then under the action of the electromagnetic field, the magnet block 312 moves away from the electromagnet 309, and in the process of the movement of the magnet block 312, the extrusion plate 311 is driven to move and stretch the second spring 310, and in the process of the movement of the extrusion plate 311, the piston plate 305 is driven to move and compress the first spring 306, and then in the process of the movement of the piston plate 305, the piston plate 305 is moved by the mounting plate 312. The mounting rod 307 drives the fixing plate 308 to fix the inner wall of the welding pipe 1 and the arc-starting pipe 2 respectively. At this time, the positions of the welding pipe 1 and the arc-starting pipe 2 are fixed, and then the user can rotate the threaded rod 301. Since the threaded rod 301 is threadedly connected with the linkage block 302, and the linkage block 302 cannot be rotated under the action of the telescopic tube 303, the threaded rod 301 drives the linkage block 302 to approach the mounting block 313 during the rotation process, and drives the arc-starting pipe 2 through the sleeve 304, the mounting rod 307, and the fixing plate 308 during the movement process. The second spring 310 is stretched by the extrusion plate 311, and the extrusion plate 311 gradually contacts the push rod 404, and drives the push rod 404 to move along the slide groove. At this time, the reset spring 405 is compressed and has a tendency to recover. During the movement of the push rod 404, the push rod 404 gradually contacts the inclined surface of the spring telescopic rod 401, and applies a thrust to the inclined surface of the spring telescopic rod 401. Then, the spring telescopic rod 401 is driven to move under the action of the thrust. At this time, the third spring 402 is compressed and has a tendency to recover. At the same time, during the movement of the spring telescopic rod 401, the output end of the spring telescopic rod 401 contracts and has a tendency to recover, and then the spring telescopic rod 401 is driven to move during the movement of the piston plate 305, and after the fixed plate 308 is fitted with the inner wall of the arc-striking tube 2, the output end of the spring telescopic rod 401 contacts the fixed groove 403, at which time the output end of the spring telescopic rod 401 stretches and is inserted into the fixed groove 403, at which time the piston plate 305 is fixed, that is, at this time the fixed plate 308 is fixed and cannot move, thereby preventing the fixed plate 308 from moving during the arc-striking process;During the process of the piston plate 305 moving and compressing the first spring 306, the pressure in the space on the side of the piston plate 305 close to the extrusion plate 311 in the sleeve 304 decreases, and then the sealing rod 504 is driven to move during the movement of the piston plate 305, and the sealing rod 504 gradually contacts with the sleeve 304 during the movement, and then the sleeve 304 drives the sealing rod 504 to squeeze the fourth spring 505, and after the fixed plate 308 is in contact with the inner wall of the arc-starting tube 2, the sealing rod 504 drives the connecting groove 506 to connect with the first air pipe 503. At this time, under the action of pressure, the space on the side of the piston plate 305 close to the extrusion plate 311 in the sleeve 304 sucks air from the fixed cavity 501 through the connecting groove 506 and the first air pipe 503, and makes the fixed cavity 501 negatively pressurized. At this time, the fixed cavity 501 tends to suck air through the air hole 502. The fixed plate 308 fits with the inner wall of the arc-starting tube 2, so the fixed plate 308 and the arc-starting tube 2 are tightly sucked together under the action of pressure, thereby preventing the arc-starting tube 2 from rotating; when the piston plate 305 drives the fixed plate 308 to clamp the arc-starting tube 2 through the mounting rod 307, the piston plate 305 drives the air flow in the space on the side of the piston plate 305 away from the extrusion plate 311 in the sleeve 304 to flow into the fixed cavity 501 through the second air pipe 6, and blows to the inner wall of the arc-starting tube 2 through the air hole 502 on the fixed cavity 501, thereby preventing dust from forming on the inner wall of the arc-starting tube 2 and affecting the fitting effect of the arc-starting tube 2 and the fixed plate 308; before fixing the arc-starting tube 2, the arc-starting groove 7 on the arc-starting tube 2 can be fitted with the limiting plate 9, and then the arc-starting groove 7 can be aligned with the welding groove on the pipe 1 to be welded under the action of the limiting plate 9, thereby further improving the arc-starting effect. ;

[0054] The above is only a preferred specific implementation of the present invention; however, the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and its improved conception within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An arc-starting device for a straight seam submerged arc welded steel pipe, comprising a pipe to be welded (1) and an arc-starting tube (2), wherein a mounting block (313) is movably mounted on the pipe to be welded (1) and the arc-starting tube (2), and a fixing component (3) is provided on the mounting block (313); Features: The fixing assembly (3) comprises a threaded rod (301) rotatably mounted on a mounting block (313); a linking block (302) is threadedly mounted on the threaded rod (301); a telescopic tube (303) is commonly mounted between the linking block (302) and the mounting block (313); a sleeve (304) is fixedly mounted on both the linking block (302) and the mounting block (313); a piston plate (305) is slidably mounted in the sleeve (304); a first spring (306) is commonly fixedly mounted between the piston plate (305) and the sleeve (304); the piston plate (304) is fixedly mounted on the sleeve (304); 5) is fixedly mounted with a mounting rod (307), a fixing plate (308) is fixedly mounted on one end of the mounting rod (307) away from the piston plate (305), an electromagnet (309) is embedded on the mounting block (313), a second spring (310) is fixedly mounted on the side wall of the sleeve (304), an extrusion plate (311) is fixedly mounted on one end of the second spring (310) away from the sleeve (304), a magnet block (312) is embedded on the extrusion plate (311), and a locking assembly (4) cooperating with the extrusion plate (311) is provided on the piston plate (305).

2. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 1, characterized in that: The locking assembly (4) comprises a mounting groove provided on the piston plate (305), a spring telescopic rod (401) being slidably installed in the mounting groove, a third spring (402) being fixedly installed between the spring telescopic rod (401) and the mounting groove, a fixing groove (403) cooperating with the output end of the spring telescopic rod (401) being provided on the side wall of the sleeve (304), and an end of the spring telescopic rod (401) away from the fixing groove (403) is an inclined surface, a sliding groove is provided on the piston plate (305), a push rod (404) being slidably installed in the sliding groove, and a return spring (405) being fixedly installed between the push rod (404) and the sliding groove.

3. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 2, characterized in that: The fixed plate (308) is provided with a fixed cavity (501), the fixed cavity (501) is evenly provided with air holes (502), the fixed cavity (501) is inserted with a first air pipe (503), a sealing rod (504) is slidably installed on the piston plate (305), a fourth spring (505) is installed between the sealing rod (504) and the piston plate (305), and the sealing rod (504) is provided with a connecting groove (506) connected with the first air pipe (503).

4. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 3, characterized in that: The mounting rod (307) is provided with a second air pipe (6) which is in communication with the fixing cavity (501).

5. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 4, characterized in that: The arc-striking tube (2) is provided with an arc-striking groove (7), the mounting block (313) is provided with a vertical groove (8), a limit plate (9) cooperating with the arc-striking groove (7) is slidably mounted in the vertical groove (8), and a third air pipe (10) connected to the telescopic tube (303) is inserted into the vertical groove (8).

6. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 1, characterized in that: The sleeve (304) is fixedly mounted with an exhaust valve (11) whose output end is connected to the outside.

7. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 2, characterized in that: The output end of the spring telescopic rod (401) is a cone surface.

8. The arc starting device for a straight seam submerged arc welded steel pipe according to claim 2, characterized in that: The bottom wall of the push rod (404) is a smooth mirror surface.

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