CN117226373A - Pipeline welding equipment and welding method - Google Patents

Abstract

The application relates to the field of pipeline welding, in particular to pipeline welding equipment, which comprises a movable base, a pipe supporting oil cylinder arranged on the base, a bottom rod arranged on a power rod of the pipe supporting oil cylinder, two groups of bottom wheels which are arranged on the bottom rod and are used for being placed at the end parts of two sections of pipelines in a one-to-one correspondence manner, a pipe pressing oil cylinder arranged on the base, a push rod arranged on the power rod of the pipe pressing oil cylinder, a top wheel arranged on the push rod and abutted against the upper part of the pipeline, two opposite blocks which are connected to the base in a sliding manner, an opposite block motor which is arranged on the base and can drive the two opposite blocks to be close to or far away from each other, a flat rotating block which is connected to the opposite blocks Xiang Kuai in a rotating manner, two main semi-rings which are arranged on the two flat rotating blocks in a one-to-one correspondence manner and can be close to or far away from each other, a polishing piece which can be connected to the two main semi-rings in a one-to-one correspondence manner around the pipeline axis, and a polishing piece which can move along with the operation blocks and polish a pipeline groove, and a welding head which is welded.

Description

Pipeline welding equipment and welding method

Technical Field

The application relates to the field of pipeline welding, in particular to pipeline welding equipment and a welding method.

Background

Ethylene is used as a chemical basic product with large dosage, and is mainly conveyed by virtue of pipelines, and generally, a steel pipe lined with three layers of polyethylene is used for conveying ethylene, so that the steel pipe is not easy to pass through in the ethylene conveying process to cause larger corrosion. The length of the pipeline required in the long-distance conveying process is long, and for this purpose, several standard pipelines need to be welded on site.

The prior pipe fitting welding device with the groove pretreatment function has the advantages that the two sections of pipelines are respectively placed in corresponding to two righting annular sleeves, so that the two sections of pipelines are aligned, then the operation top plate drives the polishing part to rotate around the axis of the pipeline so as to polish the groove of the pipeline, and after polishing, the polishing part is detached and the welding head is installed so as to weld the pipeline.

Aiming at the related technology, when welding is carried out on an installation site, the installation of one section of pipeline is finished firstly, then the other section of pipeline to be welded is moved and the installed pipeline is finished to be aligned, polishing and welding are carried out, and after the welding is finished, the whole welding device is required to be axially moved to the position to be welded at the other end along the pipeline, so that the welding device is very inconvenient and difficult to adapt to the welding operation of the pipeline on site.

Disclosure of Invention

In order to be better suitable for pipeline field welding operation, the application provides pipeline welding equipment and a welding method.

In a first aspect, the present application provides a pipe welding apparatus according to the following technical solution.

The utility model provides a pipeline welding equipment, including the base that can remove, locate the stay tube hydro-cylinder of base, locate the sill bar of stay tube hydro-cylinder power pole, locate the sill bar and two sets of return pulleys that supply two sections pipeline tip to place of one-to-one, locate the press tube hydro-cylinder of base, locate the ejector pin of press tube hydro-cylinder power pole, locate the ejector pin and butt in the top wheel on pipeline upper portion, sliding connection is in two opposite blocks of base, locate the base and can drive two opposite blocks and be close to or keep away from mutually, rotate the flat rotating block of connecting in looks Xiang Kuai, two main semi-rings that locate two flat rotating blocks and can be close to or keep away from mutually, can rotate around pipeline axis one-to-one and connect in two main semi-rings's two operation blocks, move along with the operation piece and the piece of polishing and welding head of pipeline groove.

Through adopting above-mentioned technical scheme for after the welding is accomplished, two main semi-rings can rotate to both ends flush state, and, return pulley and top wheel homoenergetic keep away from the pipeline, so that the base can be along the radial removal of level of pipeline in pipeline, so that in the on-the-spot welding operation, take out welding equipment is whole from the pipeline, carries out continuous position movement, is applicable to pipeline on-the-spot welding more.

Optionally, the operation piece is including rotating the commentaries on classics piece of connecting in main semi-ring, interior around the pipeline axis direction rotate connect in the commentaries on classics piece and supply the outer piece that polishing piece and soldered connection set up, locate in the commentaries on classics piece and force the outer piece to keep the outer piece spring that is located in the commentaries on classics piece, locate the commentaries on classics piece and wear to locate the outer piece spring and the arc telescopic link that length can change, every main semi-ring all is equipped with the external tooth bar that can peg graft in the commentaries on classics piece, the external tooth bar can force the outer piece to outwards remove towards the commentaries on classics piece.

Through adopting above-mentioned technical scheme, because the central angle of main semi-ring is 180 for the movable range of commentaries on classics piece is less than 180, and the piece of polishing and soldered connection are difficult to fully polish or weld two sections pipeline close terminal surfaces, for this, set up outer rack in order to make when changeing the piece and follow and remove to main semi-ring and set up external rack one end department, the length that the outer piece stretches out in changeing the piece becomes longer, so that the movable range of piece and soldered connection of polishing is greater than or equal to 180, do not need operating personnel to polish or welded the complement work of pipeline close terminal surface again.

Optionally, one end of the outer block located in the rotating block is fixedly connected with an internal gear, the internal gear is meshed with an internal gear rotationally connected in the rotating block, and the external gear inserted into the rotating block can be meshed with the internal gear.

By adopting the technical scheme, the external gear can stably drive the external block to extend out of the rotating block.

Optionally, the operation block is rotationally connected with a driving gear, the main semi-ring is fixedly connected with a semi-gear meshed with the driving gear, and the operation block is provided with an operation block motor for driving the driving gear to rotate.

By adopting the technical scheme, the operation block can stably rotate.

Optionally, the pipe pressing oil cylinder is detachably connected to any one of two opposite sides of the base, and the pipe pressing oil cylinder is provided with one and connected to two ejector rods.

Through adopting above-mentioned technical scheme to according to the base needs from the more convenient shift-in of which one side of pipeline or shift out, select the mounted position of pressing the pipe hydro-cylinder on the base, and two top wheels carry out synchronous drive by a pipe hydro-cylinder that presses, the going on of the installation dismantlement work of a pipe hydro-cylinder of being convenient for, and also better control the travel distance of two top wheels, so that carry out the same pressure location to two sections pipelines.

Optionally, the opposite block includes sliding connection in the cover piece of base, sliding connection in the cover piece and supplies main semi-ring rotation connection's inserted block, and inserted block fixedly connected with piece slide bar, piece slide bar along cover piece direction of movement sliding connection in the sill bar.

By adopting the technical scheme, the height of the main semi-ring can be automatically adjusted along with the height adjustment of the bottom wheel, and the height of the main semi-ring does not need to be independently adjusted, so that the main semi-ring and the positioned pipeline axis are less prone to deviation.

Optionally, the base is rotationally connected with a bidirectional screw rod which is in threaded connection with the two opposite blocks and drives the two opposite blocks to approach or separate, and the motor of the opposite blocks drives the bidirectional screw rod to rotate.

Through adopting above-mentioned technical scheme for two opposite blocks can carry out the removal of same distance in step, make when welding at every turn, the axis of two main semi-rings is difficult for appearing the deviation, so that the piece of polishing and the welding head on two main semi-rings carry out higher quality operation of polishing and welding operation.

Optionally, the flat rotating block is located the one end department that main semi-ring is close to the base, and the piece is equipped with the flat rotating block motor that drives flat rotating block pivoted in opposite directions, and the base is equipped with the support piece that can keep away from one side butt mutually to two main semi-rings.

Through adopting above-mentioned technical scheme to when main semi-ring rotates to the state that both ends height is equal, the whole height of looks piece and main semi-ring can all be less than pipeline bottom height, so that shift out the base from pipeline below level, and, support piece can carry out better support to the height that both ends height is flush, makes the flat turning piece motor be difficult for bearing great torsional force.

Optionally, the main semi-ring rotates and connects in the flat piece that changes, and the flat piece that changes is equipped with the main semi-ring motor that drives main semi-ring pivoted, and main semi-ring axis of rotation direction perpendicular to flat piece axis of rotation direction changes, and support piece butt is in the main semi-ring one end department that keeps away from the flat piece that changes.

Through adopting above-mentioned technical scheme for when the interval between base and pipeline is less, main semi-ring can also rotate to being the horizontally state, so that welding equipment can be better adapted to the welding operation of the lower pipeline of height as a whole.

In a second aspect, the present application provides a method for welding a pipeline, which adopts the following technical scheme.

A pipeline welding method uses the pipeline welding equipment, and specifically comprises the following steps.

Step 1, a pipe supporting oil cylinder drives two groups of bottom wheels to synchronously move upwards until one group of bottom wheels is abutted to the lower part of a pipeline after installation;

step 2, one end of a pipeline to be installed is placed on a group of bottom wheels far away from the installed pipeline, and then the pipe pressing oil cylinder drives two top wheels to move downwards so as to position the ends of the two sections of pipelines to be welded;

step 3, a flat rotating block motor and a main semi-ring motor which are far away from the pipe pressing oil cylinder drive the main semi-rings to horizontally rotate to be in a vertical state, and the opposite block motor drives the two main semi-rings to approach each other until the end parts of the two main semi-rings are abutted and spliced to form a complete ring;

step 4, the operation block motor drives the operation block to rotate around the axis of the pipeline, and the polishing piece and the welding head sequentially perform corresponding polishing work and welding work;

and 5, after the welding is finished, performing the steps 1, 2 and 3 reversely, horizontally moving out the base from the lower part of the welded pipeline, and setting one end of the base, which is provided with the pipe pressing oil cylinder, as a moving front end.

Through adopting above-mentioned technical scheme, after the pipeline welding is accomplished, can follow the pipeline level radial removal of one side along the pipeline of welding equipment whole convenient as required, be suitable for on-the-spot welding.

In summary, the present application includes at least one of the following beneficial effects:

1. in the field welding operation, the whole welding equipment is taken out of the pipeline to continuously move the position, so that the welding equipment is more suitable for the field welding of the pipeline;

2. the moving range of the polishing piece and the welding head is larger than or equal to 180 degrees, and the supplementing work of polishing or welding the similar end surfaces of the pipelines by an operator is not needed.

Drawings

FIG. 1 is a schematic diagram of the main structure of the present application;

FIG. 2 is a schematic view of the construction of a work block and corresponding main half ring with the side of the rotor block away from the block slide bar in cross section;

FIG. 3 is an enlarged view at A in FIG. 2;

fig. 4 is a schematic view of the structure of fig. 2 from another perspective, from the side of the rotor toward the slide bar of the block.

Reference numerals illustrate: 1. a base; 2. a pipe supporting oil cylinder; 3. a bottom bar; 31. sleeving blocks; 32. inserting blocks; 33. a block slide bar; 34. a bidirectional screw rod; 35. a support; 36. a leveling block; 37. a main half-ring motor; 38. an operation electric cylinder; 39. a flat rotating block motor; 4. a bottom wheel; 41. a half gear; 42. a work block motor; 43. a rotating block; 44. an outer block; 45. an outer block spring; 46. an arc telescopic rod; 47. an outer rack; 48. an inner rack; 49. an internal gear; 5. a pipe pressing oil cylinder; 51. a push rod; 52. a top wheel; 53. a facing block; 54. a facing block motor; 55. a main half ring; 56. a work block; 57. a polishing member; 58. a welding head; 59. driving the gear.

Detailed Description

The present application will be described in further detail with reference to the accompanying drawings.

The embodiment of the application discloses a pipeline welding device, referring to fig. 1, which comprises a horizontal base 1, wherein universal wheels can be arranged on the bottom surface of the base 1 so as to move to the position right below the horizontal pipeline, the length direction of the base 1 is consistent with the axis direction of the pipeline, two power rods of which are vertical support pipe oil cylinders 2 are detachably connected to the upper surface of the base 1, the support pipe oil cylinders 2 can be multi-stage hydraulic oil cylinders, the power rods of the two support pipe oil cylinders 2 are fixedly connected with bottom rods 3, the length direction of the bottom rods 3 is consistent with the width direction of the base 1, a group of bottom wheels 4 are rotatably connected to the upper surface of each bottom rod 3, the vertical surface where the rotation axes of the two bottom wheels 4 are located is perpendicular to the straight line where the length direction of the base 1 is located, the circumference outside of the bottom of each section of the pipeline is abutted to the corresponding group of two bottom wheels 4, and the support pipe oil cylinders 2 can drive the bottom wheels 4 to be abutted to the bottoms of pipelines with different heights.

Referring to fig. 1, any one of two sides of the base 1 in the length direction can be detachably connected with a pipe pressing cylinder 5, the upper end of a power rod of the pipe pressing cylinder 5 is detachably connected with a push rod 51, the length direction of the push rod 51 is consistent with that of the base 1, two ends of the push rod 51 in the length direction are rotationally connected with a top wheel 52, the rotation axis direction of the top wheel 52 is consistent with that of the base 1, and the pipe pressing cylinder 5 drives the top wheel 52 to move downwards, so that the top wheel 52 is matched with a corresponding group of bottom wheels 4 to position the end part of a pipeline.

Referring to fig. 1 and 2, two opposite blocks 53 are slidably connected to the upper surface of the base 1 along the width direction of the base, each opposite block 53 includes a sleeve block 31 slidably connected to the base 1, a bidirectional screw 34 screwed to the bottom of the two sleeve blocks 31 is rotatably connected to the upper surface of the base 1, the directions of threads on two sides of the center point of the bidirectional screw 34 are opposite, the distances between the two sleeve blocks 31 and the center of the bidirectional screw 34 are equal, and the base 1 is fixedly connected with an opposite block motor 54 with an output shaft coaxially and fixedly connected to the bidirectional screw 34. The upper ends of the sleeve blocks 31 are sleeved in the vertical direction and are slidably connected with the insert blocks 32, the upper ends of the two insert blocks 32 are fixedly connected with the block slide rods 33, one ends of the two block slide rods 33, which are far away from the insert blocks 32, are slidably connected with the same bottom rod 3 along the width direction of the base 1, so that when the bottom wheel 4 is attached to the bottom of a pipeline, the height of the insert blocks 32 is adjusted. The side of the insert block 32, which is far away from the self-connected block slide rod 33, is rotationally connected with a flat rotating block 36, the rotating axis direction of the flat rotating block 36 is consistent with the length direction of the base 1, the insert block 32 is fixedly connected with a flat rotating block motor 39 of which an output shaft is coaxially and fixedly connected to the rotating point of the flat rotating block 36, and the flat rotating block 36 is provided with a main semi-ring 55 with a central angle of 180 degrees, so that the main semi-ring 55 can be converted between a state that two ends are flush and two ends are positioned in the same vertical line.

Referring to fig. 1 and 2, the main half ring 55 is rotatably connected to the leveling block 36, the leveling block 36 is fixedly connected to the main half ring motor 37 having an output shaft coaxially and fixedly connected to a rotation point of the main half ring 55, and when both ends of the main half ring 55 are leveled, a rotation axis direction of the main half ring 55 is consistent with a width direction of the base 1, so that the main half ring 55 is converted from a vertical state where both ends are leveled to a horizontal state where both ends are leveled, and when a space between the pipe and an upper surface of the base 1 is small, the main half ring 55 is turned to be horizontal so as to smoothly move from below the pipe. The upper surface of the base 1 is fixedly connected with two groups of two supporting pieces 35, and the two supporting pieces 35 in the same group can be abutted to the lowest position of different states when the two ends of the corresponding main semi-ring 55 are level.

Referring to fig. 2 and 3, after the main half rings 55 are turned into a state in which both ends are located in the same vertical direction, the two main half rings 55 are close to each other until the two main half rings 55 are spliced to form a complete ring, so that the axis of the main half ring 55 is consistent with the axis of the pipe. The end face of each main semi-ring 55 is rotatably connected with a working block 56 around the axis of the main semi-ring. When the two main half rings 55 are abutted, the connecting line of the two working blocks 56 always passes through the axis of the main half ring 55. The operation block 56 comprises a rotation block 43 which is rotationally connected with the main semi-ring 55, the rotation block 43 is of an arc shape with the same axis as the main semi-ring 55, one end of the rotation block 43 is sleeved around the axis of the rotation block 43 and is in sliding connection with an outer block 44, the outer block 44 is also of an arc shape with the same axis as the main semi-ring 55, two operation cylinders 38 are detachably connected at the inner ring of the outer block 44, a polishing piece 57 and a welding head 58 are fixedly connected with power rods of the two operation cylinders 38 in one-to-one correspondence, the polishing piece 57 is closer to the rotation block 43 than the welding head 58, the polishing piece 57 is attached to a pipeline groove for polishing, and the welding head 58 is attached to the pipeline groove for welding.

Referring to fig. 4, a partially exposed driving gear 59 is rotatably connected to the rotating block 43, the outer ring of the main half ring 55 is coaxially and fixedly connected to the half gear 41, the half gear 41 is in an arc shape with the same axis as the main half ring 55, the driving gear 59 is meshed with the half gear 41, and the rotating block 43 is fixedly connected to an output shaft which is coaxially and fixedly connected to the operation block motor 42 driving the gear 59, so that the rotating block 43 can rotate around the axis of the main half ring 55 to drive the grinding member 57 and the welding head 58 to rotate around the axis of the main half ring 55.

Referring to fig. 2 and 3, the working block 56 further includes an arc telescopic rod 46 fixedly connected to one end of the rotating block 43 located in the rotating block 43 and inside the rotating block 43, the arc telescopic rod 46 is in an arc shape with an axis coincident with that of the outer block 44, and the arc telescopic rod 46 is in a structure that a rod is inserted into a tube, so that the length of the arc telescopic rod 46 can be changed. The arc telescopic rod 46 is inserted with an outer block spring 45, and the outer block spring 45 forces the outer block 44 to move towards the inside of the rotating block 43. The two main semi-rings 55 keep away from the equal fixedly connected with of one end and are arc-shaped external tooth bar 47, external tooth bar 47 axis and main semi-rings 55 axis are unanimous, the external shoe 44 is located the internal tooth bar 48 that one end fixedly connected with is arc-shaped in the commentaries on classics piece 43, internal tooth bar 48 meshing has the rotation to connect in the inside internal gear 49 of commentaries on classics piece 43, external tooth bar 47 can peg graft in commentaries on classics piece 43 and mesh in internal gear 49 for when commentaries on classics piece 43 moves to the position department that main semi-rings 55 set up external tooth bar 47, the external tooth bar 47 is located to commentaries on classics piece 43 cover, make external tooth bar 44 constantly outwards remove, make commentaries on classics piece 43's range of movement be greater than or equal to 180, in order to encircle the pipeline tip and carry out abundant polishing and welding operation.

The implementation principle of the pipeline welding equipment provided by the embodiment of the application is as follows: after the welding operation is completed, the opposite block motor 54 drives the two sleeve blocks 31 to be away from each other, so that the two main semi-rings 55 are away from each other, meanwhile, the parallel rotating block motor 39 drives the parallel rotating block 36 to rotate, so that the main semi-rings 55 are converted into a state that two ends are flush from a state that two ends are vertical, and when the distance between the bottom of the pipeline and the upper surface of the base 1 is smaller, the main semi-ring motor 37 can also drive the main semi-rings 55 to rotate, so that the main semi-rings 55 are converted into a horizontal state from vertical, and the main semi-rings 55 smoothly pass through the lower part of the pipeline. Then the pipe pressing cylinder 5 drives the top wheel 52 to move upwards, the pipe supporting cylinder 2 drives the bottom wheel 4 to move downwards, and then the base 1 is moved away from the lower part of the pipeline along the horizontal radial direction of the pipeline so as to carry out subsequent welding operation.

The embodiment of the application also discloses a pipeline welding method, which comprises the following steps.

Step 1, a pipe supporting oil cylinder 2 drives two groups of bottom wheels 4 to synchronously move upwards until one group of bottom wheels 4 is abutted to the lower part of a pipeline after installation;

step 2, placing one end of a pipeline to be installed on a group of bottom wheels 4 far away from the installed pipeline, and then driving two top wheels 52 to move downwards by a pipe pressing oil cylinder 5 so as to position the ends of the two sections of pipelines to be welded;

step 3, a flat rotating block motor 34 and a main semi-ring motor 37 which are far away from the pipe pressing oil cylinder 5 drive the main semi-rings to horizontally rotate to be in a vertical state, and a facing block motor 54 drives two main semi-rings 55 to approach each other until the end parts of the two main semi-rings 55 are abutted and spliced to form a complete ring;

step 4, the operation block motor 42 drives the operation block 56 to rotate around the axis of the pipeline, and the polishing piece 57 and the welding head 58 sequentially perform corresponding polishing work and welding work;

and 5, after the welding is finished, performing the steps 1, 2 and 3 reversely, horizontally removing the base 1 from the lower part of the welded pipeline, and setting one end of the base 1, which is provided with the pipe pressing oil cylinder 5, as a moving front end.

The implementation principle of the pipeline welding method of the embodiment of the application is as follows: the pipe pressing cylinder 5 can be arranged at any side of the upper surface of the base 1 in the length direction according to the requirement so as to smoothly remove the base 1.

The above embodiments are not intended to limit the scope of the present application, so: all equivalent changes in structure, shape and principle of the application should be covered in the scope of protection of the application.

Claims (10)

1. A pipe welding apparatus, characterized in that: the welding device comprises a movable base (1), a supporting tube oil cylinder (2) arranged on the base (1), a bottom rod (3) arranged on a power rod of the supporting tube oil cylinder (2), two groups of bottom wheels (4) arranged on the bottom rod (3) and used for being placed at the end parts of two sections of pipelines in a one-to-one correspondence mode, a tube pressing oil cylinder (5) arranged on the base (1), a push rod (51) arranged on the power rod of the tube pressing oil cylinder (5), a top wheel (52) arranged on the push rod (51) and abutted to the upper part of a pipeline, two opposite blocks (53) connected to the base (1) in a sliding mode, opposite block motors (54) arranged on the base (1) and used for driving the two opposite blocks (53) to be close to or far away from each other, two main semi-rings (55) which are arranged in a one-to-one correspondence mode, two operation blocks (56) which are connected to the two main semi-rings (55) in a one-to-one correspondence mode and a welding head (58) which is used for welding a polishing piece (57) which moves along with the operation blocks (56) and polishes a pipeline groove.

2. A pipe welding apparatus according to claim 1, wherein: the operation block (56) comprises a rotating block (43) which is connected to the main semi-ring (55) in a rotating mode, an outer block (44) which is connected to the rotating block (43) in a rotating mode and used for being arranged on a polishing piece (57) and a welding head (58) in a rotating mode, an outer block spring (45) which is arranged in the rotating block (43) and used for forcing the outer block (44) to be located in the rotating block (43), and an arc telescopic rod (46) which is arranged in the rotating block (43) and penetrates through the outer block spring (45) and can be changed in length, wherein an outer tooth bar (47) which can be inserted into the rotating block (43) is arranged on each main semi-ring (55), and the outer tooth bar (47) can force the outer block (44) to move outwards towards the rotating block (43).

3. A pipe welding apparatus according to claim 2, wherein: one end of the outer block (44) positioned in the rotating block (43) is fixedly connected with an inner gear (48), the inner gear (48) is meshed with an inner gear (49) rotatably connected in the rotating block (43), and the outer gear (47) inserted into the rotating block (43) can be meshed with the inner gear (49).

4. A pipe welding apparatus according to claim 1, wherein: the operation block (56) is rotationally connected with a driving gear (59), the main semi-ring (55) is fixedly connected with a semi-gear (41) meshed with the driving gear (59), and the operation block (56) is provided with an operation block motor (42) for driving the driving gear (59) to rotate.

5. A pipe welding apparatus according to claim 1, wherein: the pipe pressing oil cylinder (5) is detachably connected to any one of two opposite sides of the base (1), and the pipe pressing oil cylinder (5) is provided with one and connected to two ejector rods (51).

6. A pipe welding apparatus according to claim 1, wherein: the opposite blocks (53) comprise sleeve blocks (31) which are connected to the base (1) in a sliding mode, inserting blocks (32) which are connected to the sleeve blocks (31) in a sliding mode and are used for enabling the main semi-rings (55) to be connected in a rotating mode, block sliding rods (33) are fixedly connected to the inserting blocks (32), and the block sliding rods (33) are connected to the bottom rods (3) in a sliding mode along the moving direction of the sleeve blocks (31).

7. A pipe welding apparatus according to claim 1, wherein: the base (1) is rotationally connected with two opposite blocks (53) in threaded connection and drives two opposite blocks (53) to approach or separate from a bidirectional screw rod (34), and an opposite block motor (54) drives the bidirectional screw rod (34) to rotate.

8. A pipe welding apparatus according to claim 1, wherein: the flat rotating block (36) is positioned at one end of the main semi-ring (55) close to the base (1), the opposite block (53) is provided with a flat rotating block motor (39) for driving the flat rotating block (36) to rotate, and the base (1) is provided with a supporting piece (35) which can be abutted against one side of the two main semi-rings (55) away from each other.

9. A pipe welding apparatus as defined in claim 8, wherein: the main semi-ring (55) is rotationally connected to the flat rotating block (36), the flat rotating block (36) is provided with a main semi-ring motor (37) for driving the main semi-ring (55) to rotate, the rotation axis direction of the main semi-ring (55) is perpendicular to the rotation axis direction of the flat rotating block (36), and the supporting piece (35) is abutted to one end, far away from the flat rotating block (36), of the main semi-ring (55).

10. A pipe welding method using a pipe welding apparatus according to any one of claims 1 to 9, characterized in that: the method specifically comprises the following steps:

step 1, a pipe supporting oil cylinder (2) drives two groups of bottom wheels (4) to synchronously move upwards until one group of bottom wheels (4) is abutted to the lower part of a pipeline after installation;

step 2, one end of a pipeline to be installed is placed on a group of bottom wheels (4) far away from the installed pipeline, and then a pipe pressing oil cylinder (5) drives two top wheels (52) to move downwards so as to position the end parts of the two sections of pipelines to be welded;

step 3, a flat rotating block motor (39) and a main semi-ring motor (37) which are far away from the pipe pressing oil cylinder (5) drive the main semi-rings (55) to horizontally rotate to be in a vertical state, and the opposite block motor (54) drives the two main semi-rings (55) to approach to each other until the end parts of the two main semi-rings (55) are abutted and spliced to form a complete ring;

step 4, a working block motor (42) drives a working block (56) to rotate around the axis of the pipeline, and a polishing piece (57) and a welding head (58) sequentially perform corresponding polishing work and welding work;

and 5, after the welding is finished, performing the steps 1, 2 and 3 reversely, horizontally removing the base (1) from the lower part of the welded pipeline, wherein one end of the base (1) provided with the pipe pressing oil cylinder (5) is a moving front end.