Spiral welding method and device for periphery of cylindrical object

Abstract

The invention discloses a spiral welding method for the periphery of a cylindrical object. The spiral welding method comprises the steps that the cylindrical object with a spiral object arranged on the periphery is fixed to a rotating mechanism; the rotating mechanism drives the cylindrical object to rotate; the welding mechanism ascends and descends, and the spiral object and the cylindrical object are welded in the spiral direction of the spiral object; and the spray cooling mechanism sprays cooling liquid to the inner wall of the cylindrical object. The invention further discloses a cylindrical object periphery spiral welding device which comprises a rotating mechanism, a welding mechanism and a spray cooling mechanism, the rotating mechanism is used for vertically placing the cylindrical object, and the welding mechanism is arranged on one side of the rotating mechanism in a lifting mode. The welding device is used for vertically ascending or vertically descending and welding the spiral object and the cylindrical object in the spiral direction of the spiral object. The spiral welding method and device for the periphery of the cylindrical object have the advantages that positioning is convenient and accurate, the welding efficiency and quality can be improved, and cooling liquid can be conveniently collected.

Description

Technical Field

[0001] The invention relates to the technical field of food and medicine packaging machinery and equipment, and in particular to a method and a device for spiral welding the outer circumference of a cylindrical object. Background Art

[0002] The jacket of the bioengineering tank is generally a half-tube of multiple specifications, which is rolled into a spiral shape and then welded to the outer wall of the tank. Steam or hot water and other media are generally passed into the half-tube to regulate the temperature of the tank during the pharmaceutical or chemical process.

[0003] The existing welding of spirals and tank bodies is generally carried out by using a welding device for vertically rotating objects, such as the automatic tracking welding equipment for heat exchange coils disclosed in the Chinese patent document with application number 201310149541.6, the manufacturing method of embossing tools and embossing tools disclosed in the German patent document with application number DE10202110114, and the manufacturing method of embossing tools and embossing tools disclosed in the Polish patent document with application number PL2020433821. The cylindrical object (such as the tank body) is welded while rotating vertically. On the one hand, when welding a spiral object outside the cylindrical object, the spiral object is placed horizontally (the central axis is horizontal), and the runout is large, resulting in poor welding effect and quality; on the other hand, the horizontal placement of the cylindrical object requires positioning at both ends, which is inconvenient to operate and difficult to position, and is prone to inaccurate positioning, resulting in poor welding effect; on the third hand, the spray cooling mechanism needs to be horizontally extended into the tank body for spray cooling, which is inconvenient to set up and inconvenient to collect the coolant.

[0004] The existing welding device (horizontal welding device) for vertical rotation of objects is used, such as the automatic tracking welding equipment for heat exchange coils disclosed in the application number 201310149541.6. The welding process is to first weld the head to the tank body, then place the tank body horizontally (central axis horizontally) on the tank body rotating device, and then the tank body rotating device drives the tank body to rotate vertically, and the welding device welds the spiral half-tube to the tank body. It has the following shortcomings: 1) It can only perform vertical rotation welding on the spiral half-tube and the tank body. The tank body is placed horizontally and needs to be positioned at both ends, which is inconvenient to operate and difficult to position. It is easy to be positioned incorrectly, resulting in poor welding effect; 2) The spray cooling mechanism needs to be horizontally extended into the tank body for spray cooling, which is inconvenient to set up and inconvenient to collect the coolant. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a method and device for spiral welding the periphery of a cylindrical object, which is convenient and accurate in positioning, can improve welding efficiency and quality, and is convenient for collecting coolant.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A method for spiral welding the outer circumference of a cylindrical object comprises the following steps:

[0008] S1. A cylindrical object with a spiral object on its outer circumference is fixed vertically or obliquely on a horizontal rotating mechanism relative to the ground plane;

[0009] S2. The rotating mechanism drives the cylindrical object to rotate around the central axis of the cylindrical object; the welding mechanism moves up and down along the axial direction of the cylindrical object, and welds the spiral object and the cylindrical object along the spiral direction of the spiral object; the spray cooling mechanism sprays cooling liquid onto the inner wall of the cylindrical object.

[0010] As a further improvement of the above technical solution:

[0011] The spraying direction of the spray cooling mechanism is upward.

[0012] In S2, the shielding gas spraying mechanism sprays shielding gas toward the welding point.

[0013] The method further includes step S3, turning over and fixing the cylindrical object on the rotating mechanism upside down, and repeating step S2.

[0014] A spiral welding device for the outer periphery of a cylindrical object comprises a rotating mechanism, a welding mechanism and a spray cooling mechanism. The rotating mechanism is used to fix and rotate the cylindrical object vertically or inclined relative to the ground plane around the central axis of the cylindrical object. The welding mechanism is lifted and arranged on one side of the rotating mechanism, and is used to perform an axial lifting and lowering movement of the cylindrical object when the cylindrical object rotates, and to weld the spiral object and the cylindrical object along the spiral direction of the spiral object. The spray cooling mechanism is fixedly arranged, and is used to spray cooling liquid onto the inner wall of the cylindrical object.

[0015] As a further improvement of the above technical solution:

[0016] The rotating mechanism comprises a bearing platform and a rotating driving assembly for driving the bearing platform to rotate. The bearing platform is provided with a fixing mechanism for fixing the cylindrical object. The nozzle of the spray cooling mechanism is located in the middle of the bearing platform.

[0017] A liquid collecting tank is provided below the carrying platform, and the projection of the carrying platform in the vertical direction is located in the liquid collecting tank.

[0018] The cylindrical object outer circumference spiral welding device further comprises a lifting mechanism arranged on one side of the rotating mechanism, and the welding mechanism is arranged on the lifting mechanism.

[0019] The cylindrical object outer periphery spiral welding device also includes a protective gas spraying mechanism, and the protective gas spraying mechanism is used to spray protective gas to the welding point when the welding mechanism is welding.

[0020] The cylindrical object outer periphery spiral welding device also includes a spray cooling mechanism, which is used to spray cooling medium onto the welding point when the welding mechanism is welding.

[0021] Compared with the prior art, the advantages of the present invention are:

[0022] The spiral welding method for the outer periphery of a cylindrical object of the present invention, in the first aspect, the cylindrical object is fixed on the rotating mechanism vertically or obliquely relative to the ground plane, and the spiral object is placed vertically and also fixed on the rotating mechanism vertically or obliquely relative to the ground plane, and is relatively horizontally arranged, so that the jump is small during rotation welding, and the welding effect and quality are high. In addition, since the welding path is an arc, the molten slurry just welded flows downward due to gravity, and the molten slurry on the upper side is less and smoother, so that the weld quality is better and more beautiful; in the second aspect, the cylindrical object placed vertically or obliquely relative to the ground plane can be fixed and positioned only at the bottom end of the cylindrical object, and the relatively horizontal placement requires positioning at both ends, which is convenient to operate and difficult to position. Small and easy to position accurately; thirdly, since the cylindrical object is placed vertically or tilted relative to the ground for welding, the spray cooling mechanism can spray from the top of the cylindrical object downward or the bottom upward, and the coolant can flow from top to bottom along the inner wall of the cylindrical object, thereby achieving the effect of overall flow cooling of the cylindrical object, which not only improves the cooling effect, but also facilitates the collection of coolant under the cylindrical object, and is also convenient for the setting of the spray cooling mechanism (there is no need to set a nozzle over a large area in the cylindrical object for overall cooling, as is the case with horizontally placed cylindrical objects); fourthly, the overall step design is reasonable, which not only improves welding efficiency, but also improves welding quality.

[0023] The spiral welding device for the outer periphery of a cylindrical object of the present invention has the following advantages: first, the cylindrical object is fixed on the rotating mechanism vertically or obliquely relative to the ground plane, and the spiral object is also fixed on the rotating mechanism vertically or obliquely relative to the ground plane. The vibration is small during the rotation welding, and the welding effect and quality are high. In addition, since the welding path is arc-shaped, the molten slurry just welded flows downward due to gravity, and the molten slurry on the upper side is less and smoother, so that the weld quality is better and more beautiful. Second, the cylindrical object placed vertically or obliquely relative to the ground plane is fixed and positioned at the bottom end of the cylindrical object by the rotating mechanism, and the two ends need to be positioned relatively horizontally, which is convenient to operate, has low positioning difficulty, and is easy to position accurately. Third, since the cylindrical object is placed vertically or obliquely relative to the ground plane, The object can be placed at an angle for welding, and the spray cooling mechanism can spray from the top of the cylindrical object downward or the bottom upward, and the coolant can flow from top to bottom along the inner wall of the cylindrical object, thereby achieving the effect of overall flow cooling of the cylindrical object, which not only improves the cooling effect, but also facilitates the collection of coolant under the cylindrical object, and is also convenient for the setting of the spray cooling mechanism (there is no need to set a large area of ​​nozzles in the cylindrical object for overall cooling like a horizontally placed cylindrical object); fourthly, through the coordination of the rotational motion of the rotating mechanism and the lifting motion of the welding mechanism, the spiral object and the cylindrical object can be welded along the spiral direction of the spiral object. The overall structural design is ingenious, which not only improves the welding efficiency, but also improves the welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the main structure of the spiral welding device for the outer periphery of a cylindrical object of the present invention.

[0025] Figure 2 It is a schematic diagram of the top view of the structure of the spiral welding device for the outer periphery of a cylindrical object of the present invention.

[0026] Figure 3 It is another structural schematic diagram of the spiral welding device for the outer periphery of a cylindrical object of the present invention.

[0027] The symbols in the figure represent:

[0028] 1. Rotating mechanism; 11. Carrying platform; 12. Rotating drive assembly; 2. Welding mechanism; 3. Spray cooling mechanism; 4. Liquid collecting tank; 5. Fixing mechanism; 6. Lifting mechanism; 7. Protective gas spraying mechanism; 8. Spray cooling mechanism; 9. Cylindrical object; 91. Spiral object. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present invention.

[0031] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0032] In the present invention, unless otherwise clearly specified and limited, the terms "assembled", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between 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 specific circumstances.

[0033] Embodiment 1:

[0034] An embodiment of the method for spiral welding on the outer periphery of a cylindrical object of the present invention includes the following steps:

[0035] S1. The cylindrical object 9 with a spiral object 91 on its outer periphery is fixedly arranged vertically or obliquely relative to the ground plane on the rotating mechanism 1;

[0036] S2. The rotating mechanism 1 drives the cylindrical object 9 to rotate around the central axis of the cylindrical object 9 (i.e., the cylindrical object 9); the welding mechanism 2 moves up and down along the axial direction of the cylindrical object 9 and welds the spiral object 91 and the cylindrical object 9 along the spiral direction of the spiral object 91; the spray cooling mechanism 3 sprays coolant onto the inner wall of the cylindrical object 9.

[0037] In the present method for spiral welding of the periphery of a cylindrical object, on the first hand, the cylindrical object 9 is fixed on the rotating mechanism 1 vertically or obliquely relative to the ground plane, and the spiral object 91 is also fixed on the rotating mechanism 1 vertically or obliquely relative to the ground plane (the central axes of the cylindrical object 9 and the spiral object 91 are vertically or obliquely relative to the ground plane), and are relatively horizontally arranged (the central axes of the cylindrical object 9 and the spiral object 91 are parallel to the ground plane), so that the vibration is small during rotation welding, and the welding effect and quality are high. In addition, since the welding path is an arc, the molten slurry just welded flows downward due to gravity, and the molten slurry on the upper side is less and smoother, so that the weld quality is better and more beautiful. On the second hand, the cylindrical object 9 placed vertically or obliquely relative to the ground plane can be fixed only at the bottom end of the cylindrical object 9. On the one hand, the cylindrical object 9 is placed vertically or tilted relative to the ground plane for welding, and the spray cooling mechanism 3 can spray from the top of the cylindrical object 9 downward or from the bottom upward, and the coolant can flow from top to bottom along the inner wall of the cylindrical object 9, which has the effect of cooling the entire cylindrical object 9. It not only improves the cooling effect, but also facilitates the collection of coolant under the cylindrical object 9, and is also convenient for the setting of the spray cooling mechanism 3 (there is no need to set a nozzle in a large area inside the cylindrical object 9 for overall cooling, as is the case with the horizontally placed cylindrical object 9); on the other hand, the overall step design is reasonable, which not only improves the welding efficiency, but also improves the welding quality.

[0038] Furthermore, in the present embodiment, the spraying direction of the spray cooling mechanism 3 is upward, and the coolant sprayed upward contacts the inner wall of the tubular object 9 more gently, further improving the cooling effect.

[0039] Furthermore, in this embodiment, in S2, the protective gas spraying mechanism 7 sprays protective gas to the weld. During welding, the protective gas spraying mechanism 7 sprays protective gas to the weld to timely protect the weld with gas to prevent the weld from being oxidized.

[0040] Furthermore, in this embodiment, step S3 is further included, wherein the cylindrical object 9 on the rotating mechanism 1 is turned over and fixed upside down, and step S2 is repeated. In this way, the two spiral seams between the spiral object 91 and the cylindrical object 9 are welded, thereby improving the overall connection strength.

[0041] Preferably, in S2, the welding mechanism 2 uses an axial lifting motion along the cylindrical object 9 to perform welding. Since the welding path is arc-shaped, the molten slurry just welded flows downward due to gravity, and welding is performed by relative horizontal movement. When welding is performed by lifting motion, it is not easy for molten slurry to accumulate between the front and rear welding points, and the welding effect is better.

[0042] Embodiment 2:

[0043] Figure 1 and Figure 2An embodiment of a spiral welding device for the periphery of a cylindrical object of the present invention is shown. The spiral welding device for the periphery of a cylindrical object of this embodiment comprises a rotating mechanism 1, a welding mechanism 2 and a spray cooling mechanism 3. The rotating mechanism 1 is used for fixing and rotating the cylindrical object 9 vertically or inclined relative to the ground plane around the central axis of the cylindrical object 9. The welding mechanism 2 is lifted and arranged on one side of the rotating mechanism 1, and is used for lifting and lowering along the axial direction of the cylindrical object 9 when the cylindrical object 9 rotates, and for welding the spiral object 91 and the cylindrical object 9 along the spiral direction of the spiral object 91. The spray cooling mechanism 3 is fixedly arranged, and is used for spraying cooling liquid onto the inner wall of the cylindrical object 9.

[0044] The use process of the spiral welding device for the periphery of a cylindrical object is as follows: first, a cylindrical object 9 with a spiral object 91 on the periphery is fixed on a rotating mechanism 1 vertically or obliquely relative to the ground plane; secondly, the rotating mechanism 1 drives the cylindrical object 9 to rotate around the central axis of the cylindrical object 9; the welding mechanism 2 moves up and down along the axial direction of the cylindrical object 9, and welds the spiral object 91 and the cylindrical object 9 along the spiral direction of the spiral object 91; the spray cooling mechanism 3 sprays cooling liquid onto the inner wall of the cylindrical object 9.

[0045] In the present device for spiral welding of the outer periphery of a cylindrical object, firstly, the cylindrical object 9 is fixed on the rotating mechanism 1 vertically or obliquely relative to the ground plane, and the spiral object 91 is also fixed on the rotating mechanism 1 vertically or obliquely relative to the ground plane (the central axes of the cylindrical object 9 and the spiral object 91 are vertically or obliquely relative to the ground plane), and the vibration is small during the rotation welding, and the welding effect and quality are high. In addition, since the welding path is arc-shaped, the molten slurry just welded flows downward due to gravity, and the molten slurry on the upper side is less and smoother, so that the weld quality is better and more beautiful; secondly, the cylindrical object 9 vertically or obliquely relative to the ground plane is fixed and positioned at the bottom end of the cylindrical object 9 by the rotating mechanism 1, and the two ends need to be positioned relative to the horizontal placement, which is convenient to operate, has low positioning difficulty, and is easy to position accurately; thirdly, since the cylindrical object 9 is placed vertically or tilted relative to the ground plane for welding, the spray cooling mechanism 3 can spray from the top of the cylindrical object 9 downward or the bottom upward, and the coolant can flow from top to bottom along the inner wall of the cylindrical object 9, thereby achieving the effect of overall flow cooling of the cylindrical object 9, which not only improves the cooling effect, but also facilitates the collection of coolant under the cylindrical object 9, and is also convenient for the setting of the spray cooling mechanism 3 (it is not necessary to set a nozzle in a large area inside the cylindrical object 9 for overall cooling like the horizontally placed cylindrical object 9); fourthly, through the coordination of the rotational motion of the rotating mechanism 1 and the lifting motion of the welding mechanism 2, the spiral object 91 and the cylindrical object 9 can be welded along the spiral direction of the spiral object 91. The overall structural design is ingenious, which not only improves the welding efficiency, but also improves the welding quality.

[0046] Furthermore, in the present embodiment, the rotating mechanism 1 includes a carrier platform 11 and a rotating drive assembly 12 for driving the carrier platform 11 to rotate. The carrier platform 11 is provided with a fixing mechanism 5 for fixing the cylindrical object 9, and the nozzle of the spray cooling mechanism 3 is located in the middle of the carrier platform 11. The carrier platform 11 is used to place the cylindrical object 9 vertically or obliquely relative to the ground plane, and the fixing mechanism 5 is used to fix the bottom end of the cylindrical object 9. The nozzle of the spray cooling mechanism 3 is located in the middle of the carrier platform 11, so that the spray direction of the spray cooling mechanism 3 is upward, and the coolant sprayed upward contacts the inner wall of the cylindrical object 9 more gently, further improving the cooling effect. The rotating drive assembly 12 is used to drive the carrier platform 11 to rotate around the central axis of the cylindrical object 9.

[0047] Furthermore, in this embodiment, a liquid collecting tank 4 is provided below the carrier 11, and the projection of the carrier 11 in the vertical direction is located in the liquid collecting tank 4. The liquid collecting tank 4 is provided below the carrier 11, and the coolant sprayed by the spray cooling mechanism 3 falls or flows downward along the inner wall of the cylindrical object 9 into the liquid collecting tank 4, so as to collect the coolant.

[0048] Furthermore, in this embodiment, the fixing mechanism 5 includes a triangular chuck. The bottom end of the cylindrical object 9 is fixed by the triangular chuck, which is easy to operate and has stable and accurate positioning. Of course, in other embodiments, the fixing mechanism 5 can also be configured to fix a designated position of the cylindrical object 9 in the axial direction inside the cylindrical object 9 according to actual requirements, such as fixing the lower part, middle part and / or upper part of the cylindrical object 9. Internal fixing does not affect external welding.

[0049] Furthermore, in this embodiment, the cylindrical object outer circumference spiral welding device further includes a lifting mechanism 6 disposed on one side of the rotating mechanism 1, and the welding mechanism 2 is disposed on the lifting mechanism 6. The lifting mechanism 6 is used to drive the welding mechanism 2 to move vertically upward or vertically downward.

[0050] Furthermore, in this embodiment, the cylindrical object outer periphery spiral welding device further includes a protective gas spraying mechanism 7, which is used to spray protective gas to the welding point when the welding mechanism 2 is welding. During welding, the protective gas spraying mechanism 7 sprays protective gas to the welding point, and performs gas protection on the welding point in time to prevent the welding point from being oxidized.

[0051] Furthermore, in this embodiment, the spiral welding device for the outer periphery of a cylindrical object further includes a spray cooling mechanism 8, which is used to spray a cooling medium onto the weld when the welding mechanism 2 is welding. During welding, in order to speed up cooling, a cooling medium can be sprayed onto the weld by the spray cooling mechanism 8. The spray cooling mechanism 8 can be turned on as needed. Of course, in other embodiments, the spray cooling mechanism 8 may not be provided. Preferably, the spray cooling mechanism 8 is provided above the rotating mechanism 1 (carrier 11).

[0052] Furthermore, in this embodiment, the rotating mechanism 1 and the welding mechanism 2 can be connected to a control module, and the control module adopts corresponding rotation speed and vertical movement speed according to the helix angle of the spiral object 91 and the outer diameter of the cylindrical object 9 to meet the welding requirements of the spiral object 91 with different helix angles and the cylindrical object 9 with different outer diameters.

[0053] Embodiment three:

[0054] Figure 3 Another embodiment of the spiral welding device for the outer periphery of a cylindrical object of the present invention is shown. The structure of the spiral welding device for the outer periphery of a cylindrical object in this embodiment is basically the same as that of the second embodiment, with the only difference being that the spray cooling mechanism 8 and the protective gas spray mechanism 7 are not provided.

[0055] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the technical content disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention should fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for spiral welding the outer periphery of a cylindrical object, characterized in that: The steps include: S1. A cylindrical object (9) with a spiral object (91) on its outer circumference is fixed on a rotating mechanism (1) vertically or obliquely relative to the ground plane; S2, the rotating mechanism (1) drives the cylindrical object (9) to rotate around the central axis of the cylindrical object (9); the welding mechanism (2) moves up and down along the axial direction of the cylindrical object (9) and welds the spiral object (91) and the cylindrical object (9) along the spiral direction of the spiral object (91); the spray cooling mechanism (3) sprays cooling liquid onto the inner wall of the cylindrical object (9).

2. The method for spiral welding the outer circumference of a cylindrical object according to claim 1, characterized in that: The spraying direction of the spray cooling mechanism (3) is upward.

3. The method for spiral welding the outer circumference of a cylindrical object according to claim 1, characterized in that: In S2, the protective gas spraying mechanism (7) sprays protective gas toward the welding point.

4. The method for spiral welding the outer circumference of a cylindrical object according to any one of claims 1 to 3, characterized in that: The method further comprises step S3, turning over and fixing the cylindrical object (9) on the rotating mechanism (1), and repeating step S2.

5. A spiral welding device for the outer periphery of a cylindrical object, characterized in that: The invention comprises a rotating mechanism (1), a welding mechanism (2) and a spray cooling mechanism (3); the rotating mechanism (1) is used to fix and rotate a cylindrical object (9) which is vertical or inclined relative to the ground plane around the central axis of the cylindrical object (9); the welding mechanism (2) is arranged to be lifted and lowered on one side of the rotating mechanism (1) and is used to perform an axial lifting movement of the cylindrical object (9) when the cylindrical object (9) rotates, and to weld the spiral object (91) and the cylindrical object (9) along the spiral direction of the spiral object (91); the spray cooling mechanism (3) is fixedly arranged and is used to spray a cooling liquid onto the inner wall of the cylindrical object (9).

6. The spiral welding device for the outer periphery of a cylindrical object according to claim 5, characterized in that: The rotating mechanism (1) comprises a carrier platform (11) and a rotating drive assembly (12) for driving the carrier platform (11) to rotate; a fixing mechanism (5) for fixing a cylindrical object (9) is provided on the carrier platform (11); and a nozzle of the spray cooling mechanism (3) is located in the middle of the carrier platform (11).

7. The spiral welding device for the outer circumference of a cylindrical object according to claim 6, characterized in that: A liquid collecting tank (4) is provided below the supporting platform (11), and a projection of the supporting platform (11) in the vertical direction is located inside the liquid collecting tank (4).

8. The spiral welding device for the outer circumference of a cylindrical object according to any one of claims 5 to 7, characterized in that: The cylindrical object outer circumference spiral welding device further comprises a lifting mechanism (6) arranged on one side of the rotating mechanism (1), and the welding mechanism (2) is arranged on the lifting mechanism (6).

9. The spiral welding device for the outer circumference of a cylindrical object according to any one of claims 5 to 7, characterized in that: The cylindrical object outer periphery spiral welding device further comprises a protective gas spraying mechanism (7), wherein the protective gas spraying mechanism (7) is used to spray protective gas onto the welding point when the welding mechanism (2) is welding.

10. The spiral welding device for the outer circumference of a cylindrical object according to any one of claims 5 to 7, characterized in that: The cylindrical object outer periphery spiral welding device further comprises a spray cooling mechanism (8), wherein the spray cooling mechanism (8) is used to spray cooling medium onto the welding point when the welding mechanism (2) is welding.

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