WELDING MACHINE FOR WELDING TWO TUBULAR PIECES

Abstract

TITLE OF THE INVENTION: WELDING MACHINE FOR WELDING TWO TUBULAR PARTS The welding machine (40) for welding two mechanically joined tubular parts (41, 42) having a common circular section defining a weld line (55), comprises: - a welding head (48), - a frame (46) supporting one of the tubular parts (41) during the operation of the welding head, - a frame (56) supporting the other of the tubular parts (42) during the operation of the welding head, - a positioner (44, 57) supporting, during the operation of the welding head, these frames in a position in which the common circular section is perpendicular to the axis of rotation (B) of the positioner and centered on this axis of rotation, and - a means (47) for moving the welding head configured to position the welding head in a fixed position opposite the weld line, during its operation. Figure for the summary: Figure 9

Description

Title of the invention: WELDING MACHINE FOR WELDING TWO TUBULAR PARTS Technical field of the invention

[0001] The present invention relates to a welding machine for welding two tubular parts. More particularly, it relates to an automatic or semi-automatic welding machine for cylindrical tubes and bent tubes. State of the art

[0002] To date, the welding of tubular parts is carried out manually or using an orbital welding machine. In this machine, welding is carried out by rotating a welding head, or welding head, at least 360° around a fixed tubular part. The rotation of the welding head around the parts poses problems of geometry of the space to be left free around the parts to be welded. In addition, the quantity of molten metal is limited by the risks of flow under the effect of gravity, which limits the quantity of metal supplied with each pass of the welding head. In other words, the deposition rate is limited by the very design of the orbital welding machine and the total duration of a welding operation of two parts is high, which limits the productivity of the welding station.

[0003] When using an orbital welding machine, the operator must remain close to the machine to carry and guide the rotating cables. He must also perform difficult movements and adopt uncomfortable postures to monitor the quality of the welding with a welding mask in his hand. Beyond the physical efforts of the operator, there is a risk of illness linked to the exposure of the eyes to radiation, particularly ultraviolet radiation, emitted by the welding arcs and to the inhalation of welding fumes.

[0004] Furthermore, the different welding passes (up to 60 rotations of the machine per weld) automatically cause significant mechanical stresses which reduce the service life of the welding machine.

[0005] Furthermore, the orbital welding machine is not suitable for welding an assembly formed by two elbows, because of the size they represent in relation to the orbital welding head as well as the guide track. In any case, welding by orbital machine is punctuated by frequent stops to check the quality of the welding. Most of the time, the control is carried out by an external service provider. These control operations are expensive and reduce the productivity of a welding machine. Summary of the invention

[0006] The welding machine according to the present invention makes it possible to overcome all or part of the undesirable effects linked to the use of the orbital machine and manual welding. In the welding machine which is the subject of the invention, instead of requiring the rotation of the head, as in an orbital welding station, an assembly consisting of the tubular parts to be welded is rotated in a sealed manner around the tangent common to their axes, at the level of the weld line. This circular weld line is perpendicular to this common tangent. During the welding operation, the welding head is held in a fixed position, opposite this circular weld line which is rotated around its center where this tangent common to the two tubular parts to be welded passes.

[0007] Preferably, the two tubular parts to be welded in a sealed manner are preliminarily made integral by at least three welding points formed on the welding line to be produced. The correct positioning on the welding machine of the assembly formed from these tubular parts is thus facilitated as well as the rotation of the second tubular component which is thus made integral with the first.

[0008] By positioning the welding head vertically to the weld line (so-called "flat" welding position), the quantity of molten metal is increased, since the risks of flow are limited. The quantity of metal supplied with each pass of the welding head is thus increased. In other words, the weld deposition rate is increased compared to an orbital welding machine. The total duration of a two-piece welding operation is thus reduced, which increases the productivity of the welding station.

[0009] Preferably, this welding machine comprises, for each part which is not cylindrical (for example, a bent part), a frame adapted to support this part during its rotation, which makes it possible to align the axis of rotation of the circular weld of the parts to be welded in a sealed manner, on the axis of rotation of the frame. Preferably, at least one of the frames has a support surface allowing the addition of a circular plate resting on a roller welding rotator allowing, if necessary, to take up the weight of all the tubular parts and the frames.

[0010] The assembly of the parts to be welded and the frame(s) (in the case of non-cylindrical parts, for example two bent tubes) is rotated (horizontal axis) by a motorized roller welding rotator or by a welding positioner.

[0011] A tool consisting of frames with standard diameters of tubes on the market then completes the welding machine. The welding head is preferably fixed on a jib and accompanied by a camera to allow an operator to remotely control the different stages of the welding process.

[0012] When no chassis is implemented, preferably, at least one spring box supports the parts to be welded and absorbs mechanical vibrations.

[0013] Preferably, the assembly to be welded is balanced by the use of counterweights in order to bring the center of gravity of the assembly back onto the axis of rotation and thus avoid any variations in the rotation speed during welding.

[0014] By rotating the part to be welded on a frame and / or using a spring box, the rotation of the assembly of parts to be welded rotates the circular welding line around its axis. The welding machine can weld tubular parts with a nominal diameter greater than 100 mm, regardless of the length of these tubular parts. Stages of the manufacturing process such as multiple intermediate quality controls are eliminated. In addition, productivity is multiplied by four compared to an orbital welding station and by ten compared to a manual welder.

[0015] This invention not only allows for an increase in production rates and welding quality, but also ensures good working conditions for the operator. The operator, away from dangerous and arduous operations, controls the quality of his work in real time, via an interactive screen. The welding machine that is the subject of the invention also improves the safety and health of operators, because they are at a distance from the welding in teleoperation and therefore away from sources of danger. Brief description of the figures

[0016] Other advantages, aims and particular characteristics of the invention will emerge from the following non-limiting description of at least one particular embodiment of the welding machine which is the subject of the present invention, with reference to the appended drawings, in which:

[0017] [Fig-1] is a schematic representation, in perspective, of a welding station comprising a first embodiment of the welding machine which is the subject of the invention,

[0018] [Fig.2] is an enlargement of a portion of [Fig.l], showing the machine of welding,

[0019] [Fig.3] is another schematic representation, in perspective, of the machine of welding illustrated in [Fig.2],

[0020] [Fig.4] is yet another schematic representation, in perspective view from below, of the welding machine illustrated in [Fig.2] and [Fig.3],

[0021] [Fig.5] represents, in side view, the welding machine illustrated in [Fig.2] at [Fig.4],

[0022] [Fig.6] represents, in front view, the welding machine illustrated in [Fig.2] at [Fig.5],

[0023] [Fig.7] represents, in top view, the welding machine illustrated in [Fig.2] at [Fig.6],

[0024] [Fig.8] represents, in the form of a flowchart, the steps of implementation of the welding machine illustrated in figures 1 to 7,

[0025] [Fig.9] represents, in perspective, a second embodiment of the machine of welding object of the invention,

[0026] [Fig. 10] is a perspective view of a first tubular part support frame,

[0027] [Fig. 11] is a perspective view of a first tubular part support frame,

[0028] [Fig. 12] represents, in front view, the welding machine illustrated in figures 9 to 11,

[0029] [Fig. 13] represents, in top view, the welding machine illustrated in figures 9 to 12, in the absence of the gallows and welding elements, and

[0030] [Fig. 14] represents, in the form of a flowchart, steps in implementing the welding machine illustrated in figures 9 to 13. Description of the embodiments

[0031] The present description is given without limitation, each characteristic of an embodiment being able to be combined with any other characteristic of any other embodiment in an advantageous manner. It should be noted from now on that the figures are not to scale.

[0032] As understood from the present description, various inventive concepts may be implemented by one or more methods or devices described below, several examples of which are provided herein. The actions or steps performed in carrying out the method or device may be ordered in any suitable manner. Accordingly, it is possible to construct embodiments in which the actions or steps are performed in a different order than illustrated, which may include performing certain acts simultaneously, even if they are presented as sequential acts in the illustrated embodiments.

[0033] The expression "and / or", as used herein, is to be understood to mean "either or both" of the elements so conjoined, i.e., elements that are present conjunctively in some cases and disjunctively in other cases. Multiple elements listed with "and / or" are to be interpreted in the same way, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present, other than the elements specifically identified by the "and / or" clause, whether or not related to those specifically identified elements. Thus, by way of non-limiting example, a reference to "A and / or B", when used in conjunction with open language such as "comprising" may refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0034] As used herein, the term "at least one," with reference to a list of one or more elements, is to be understood to mean at least one element selected from one or more elements in the list of elements, but not necessarily including at least one of each element specifically listed in the list of elements and not excluding any combination of elements in the list of elements. This definition also allows for the optional presence of elements other than the specifically identified elements in the list of elements to which the term "at least one" refers, whether or not related to those specifically identified elements.Thus, by way of non-limiting example, "at least one of A and B" (or, equivalently, "at least one of A or B", or, equivalently, "at least one of A and / or B") may refer, in one embodiment, to at least one, optionally including more than one, A, without B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, without A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0035] In the description below, all transitional expressions such as "comprising", "including", "carrying", "having", "containing", "involving", "holding", "composed of", and the like, are to be understood as open, i.e., as meaning including, but not limited to. Only the transitional expressions "consisting of" and "consisting essentially of" are to be understood as closed or semi-closed transitional expressions, respectively.

[0036] It should be noted, from now on, that the figures are not to scale.

[0037] First embodiment, figures 1 to 8

[0038] In [Fig.l], we observe a welding station comprising a welding machine 20, a protective partition 11 and a screen 12 for monitoring the welding process. The operator 13 is positioned in front of the screen 12 during the welding operations. In this position, the operator 13 is protected from the direct radiation emitted by the welding machine 20, thanks to the protective partition 11.

[0039] The welding machine 20 is shown, in different views, from [Fig. 2] to [Fig. 7]. This welding machine 20 is used for continuous and watertight welding two tubular parts 21 and 22 previously joined by spot welds to form a rigid assembly.

[0040] The parts 21 and 22 are called “tubular” because they are made up of tube truncated sections, that is to say parts which have a circular section, perpendicular to a continuous line having at least one straight, curved or broken segment. This line is called the “axis” of the tubular part. For example, the parts 21 and 22 are made up of at least one truncated cylinder with a circular directrix and / or a truncated torus. In the example illustrated in Figures 1 to 7, the part 21 is cylindrical and the part 22 is toroidal. A weld line 15 is a circular section common to the parts 21 and 22. In other words, the axes of the parts 21 and 22 are tangent at this common circular section. Prior to the positioning of these parts 21 and 22, welding points are made on the welding line 15 so that the parts 21 and 22 form a rigid assembly.Once this assembly is positioned on the machine 20, the common tangent to the axes of the parts 21 and 22 at the level of the welding line 15 is collinear with an axis of rotation A of the welding machine 20. Thus, the welding line 15, circular, rotates in its plane around its center.

[0041] The machine 20 comprises a structure 23 which also supports a means for rotating the two tubular parts 21 and 22 around this predetermined axis A.

[0042] In the first embodiment, illustrated from [Fig.l] to [Fig.7] and particularly suitable for cases where at least one of the parts to be welded is cylindrical, this rotation means takes the form of a motor 38 mounted on a drive ring 37, integral with the tubular part 21, of two non-motorized turning devices provided with upper rollers 34 and lower rollers 31 and 30, these rollers 30, 31 and 34 being in contact with the tubular part 21. As shown, one of the turning devices, referenced 24, comprises jaws 51 and 52 movable in a plane perpendicular to the axis of rotation A of the welding machine 20.Two lower movable jaws 51 rotate around the same axes as the rollers 31, between a deployed configuration, in which the part 21 can be inserted between these lower jaws 51, and a folded configuration, in which one of the lower jaws 51 places the rollers 34 carried by an upper jaw 52, ​​in support on the part 21. A locking system 53 locks the other lower jaw 51 with the upper jaw 52, ​​ensuring sufficient support for the rollers 31 and 34.

[0043] The rotation of the tubular parts 21 and 22 is driven by the fixed drive ring 37 and by the motor 38 located above the tubular parts 21 and 22, so that this motor 38 is removed with the welding assembly.

[0044] The ring 37 comprises two cylindrical half-crowns (with a circular director centered on the axis A) resting on the tubular part 21 thanks to flexible buffers 39 pinching the tubular part 21 without deforming it. The buffers 39 are adjustable in length (measured radially relative to the axis A) and interchangeable, which thus allows the mounting of the drive ring 37 on tubular parts in a wide range of diameters. Guide rollers 18 inside the drive ring 37 hold the ring 37 opposite rollers 17 driven by the motor 38. Guide rollers 19, on either side of the ring 37, make it possible to maintain the weld line 15 in line with the welding head 28 throughout the welding cycle and thus prevent the assembly of the rotating tubular parts 21 and 22 from "unscrewing" during rotation.

[0045] The rotation is thus ensured by friction by rollers driven by the motor 38, for example a stepping motor. This drive system is easily mounted and dismounted by a moderately skilled operator. The motor 38 is synchronized with the operation of a welding head 28. The speed of advance of the welding head 28 relative to the welding line 15 is proportional to the speed of rotation of the motor 38. This speed of advance is variable and is managed, like the direction of rotation, by a computer program.

[0046] Other lower rollers 30, not motorized, are carried by the structure 23 to support the tubular parts 21 and 22 at the level of a welding head 28. The welding head 28 is supported fixed relative to the structure 23, by a bracket 27. Means 32 for adjusting the height of the bracket 27 make it possible to adjust the height of the head of the welding head 28. The bracket 27 supports a horizontal beam 54 at an adjustable height.

[0047] The lower rollers 30 and 31 can be mounted on spring boxes whose springs absorb the vibrations linked to the rotation of the tubular parts 21 and 22.

[0048] Preferably, a counterweight 25 is secured to a tubular part (here the tubular part 21) by means of a peripheral connection 26 on the outer surface of the tubular part 21. This counterweight 25 is dimensioned so that the center of inertia of the assembly consisting of the two tubular parts 21 and 22, the connection 26 and the counterweight 25 is on the axis of rotation A. Thus, if none of the tubular parts 21 and 22 is bent, no counterweight 25 and no attachment 26 is put in place. If one of the tubular parts is bent, the counterweight 25 makes it possible to balance the load and thus avoids the phenomenon of unbalance during rotations.

[0049] Cables 29 supply the welding head 28. A filler metal feeder 33 supplies metal to the welding head 28.

[0050] Preferably, the structure 23, including the supports of the rollers 30 and 31, is adapted to the standard diameters of the tubes on the market, in a predetermined range of diameters, for example from 200 to 300 mm.

[0051] Preferably, a camera (not shown) is positioned next to the welding head 28 and its optical field covers at least the lower end of the head. welding 28 and the welding area. The image provided by this camera is transmitted to the supervision screen 12. This image allows the operator 13 to remotely control the various welding operations.

[0052] The structure 23 is fixed to the ground to stabilize the horizontal position of the welding machine 20. The assembly of welding elements, welding head 28, cables 29, reel 33, camera and the system for rotating the tubular parts 21 and 22 formed by the motor 38, is supported by a flexible cable 36, for example made of steel. This cable 36 allows this assembly to be placed and removed. The coupling system of the motor 38 on the drive ring 37 ensures the correct positioning of the assembly with respect to the tubular parts 21 and 22 to be welded.

[0053] By rotating the parts to be welded 21 and 22 on the structure 23, the automatic welding machine 20 makes it possible to weld tubular parts regardless of their lengths. The number of steps in the manufacturing process, such as the multiple intermediate quality controls, is greatly reduced. The output production rate is multiplied by four compared to orbital welding equipment and by ten compared to a manual welder.

[0054] [Fig-8] describes, in the form of a flowchart of a method 60, steps of implementing the device 20. This method 60 comprises, firstly, a step 61 of positioning the parts to be welded 21 and 22 in such a way that the lines tangent to their axes are merged at the level of the weld line 15, that is to say their contact line.

[0055] During a step 62, the parts to be welded 21 and 22 are mechanically secured. Preferably, this securing is carried out by spot welding on the weld line 15, for example four spot welds spaced a quarter turn apart. The parts 21 and 22 thus form a rigid assembly. Rotating the part 21 will therefore cause the part 22 to rotate.

[0056] During a step 63, this rigid assembly is placed on the welding machine 20 in such a way that the circular welding line 15 is perpendicular to the axis of rotation A and centered on this axis of rotation A and that it is located opposite the future position of the welding head 28. In the example of FIGS. 1 to 7, this involves positioning the welding line 15 slightly outside the roller 30, on the side opposite the rollers 31.

[0057] During a step 64, the jaws 51 and 52 of the turning gear 24 are closed and locked around the part 21. In addition, the drive ring 37 is mounted on the tubular part 21 by assembling its two crowns.

[0058] During a step 65, the welding assembly and the motorized system 38 are lowered to the upper crown of the motorized ring 37, by means of the bracket 27 and the flexible cable 36. Once the welding assembly and motorization positioned in such a way that the welding head 28 is located on the welding line 15, during a step 66, the system 38 is clamped on the ring 37. During a step 67, the welding assembly and the motorization system are fixed, by means of the spar 54.

[0059] During a step 68, the parts 21 and 22 are rotated and the operator 13 carries out the welding with the welding head 28, the welding generator (not shown) and the control panel 12. Of course, during step 68, the parts 21 and 22 can make several turns around the axis A without the operator having to manage the cables of the welding machine.

[0060] Once the welding of the parts 21 and 22 is completed, during a step 69, the reverse of steps 67, 66, 65 and 64 is carried out successively to move the welding assembly apart and reopen the turning gear 24. Finally, during a step 70, the parts 21 and 22 welded together are removed.

[0061] Variants

[0062] In variants of the first embodiment illustrated in figures 1 to 7: - the counterweight is positioned on the bent tubular part 22 to reduce, as close as possible to its source, the phenomenon of mechanical imbalance in the context of the assembly of two tubular parts, - to weld the largest parts, a hydraulic or mechanical system is provided to replace the counterweight to neutralize the imbalance, - the jib is independent of the structure 23, as in the second embodiment illustrated in figures 9 to 13, - height adjustment means are added to the structure 23 to make it more ergonomic and adaptable to the size of the operator 13 and / or to the diameter of the parts to be welded, and / or - the means for rotating the drive ring 37 supporting the tubular parts 21 and 22 comprise a toothed wheel instead of a friction drive. In this case, the ring 37 is, for example, perforated or crenellated.

[0063] Second embodiment, figures 9 to 14

[0064] In the second embodiment illustrated from [Fig. 9] to [Fig. 13], we find, of the welding machine 40, tubular parts 41 and 42 to be welded in a sealed manner, a rotation axis B, a welding positioner 43, a welding head 48, a jib 47 and a lower non-motorized roller turning device 50. These elements are similar to those described with regard to figures 1 to 8. However, the tubular parts 41 and 42 are mounted on two frames, respectively 46 and 56. A positioner 44 replaces the motorized system 38 and the ring 37. The frame 46 is integral with the motorized plate 57 of the positioner 44. The frame 56 is integral with a follower plate 58 of the positioner 44. Each frame 46 and 56 is thus fixed to a part tubular, respectively 41 and 42, so as to position its axis, at the level of the section to be welded, tangent to the axis B of rotation of the motorized plate 57 of the positioner 44.

[0065] The chassis 56 has the general shape of a rectangular parallelepiped, each edge of which is materialized by a metal spar. Four of these spars located on the same face of the chassis 56 carry flexible buffers 59 whose supports on the tubular part 42 are adjustable (for example by means of threaded rods) to pinch this tubular part 42 without deforming it. In the embodiment shown in Figures 9 to 13, the chassis 56 carries six buffers 59, four of which are on the horizontal faces of the tubular part 42 and two on vertical faces of the tubular part 42.

[0066] The frame 56 has a support surface allowing the addition of the circular follower plate 58 resting on a welding turner with free rollers (or "idlers") allowing, if necessary, to take up the weight of all the tubular parts and the frames. The frame 56 is more particularly adapted to tubular parts of small dimensions along their axis, for example cylindrical parts or bent tubular parts, the end sections of which form, between them, an angle less than or equal to 45 degrees.

[0067] On the contrary, the frame 46 is more particularly adapted to tubular parts of larger dimension along their axis, for example bent tubular parts, the end sections of which form, between them, an angle greater than or equal to 45 degrees, for example from 60 degrees to 135 degrees.

[0068] The chassis 46 has the general shape of a rectangular parallelepiped, each edge of which is materialized by a metal spar. In addition, four spars mounted to rotate about a vertical axis C form a rectangular frame for gripping the tubular part 41 near its free end, i.e. the end is not welded to the part 42). The spar of this rotating frame furthest from the axis of rotation C is held vertically by threaded rods whose heads move in circular slots 16 centered on the axis C formed in the stiffening plates parallel to the plane comprising the axis of the tubular part 41 (this plane is horizontal in Figures 9 to 13). This rotating frame, as well as other spars of the chassis 46, carries flexible buffers 59 for gripping the tubular part 41 without deforming it. The rotating frame allows the chassis 46 to be adapted to different curvatures of the part 42.

[0069] Preferably, each chassis 46 and 56 comprises an attachment for a counterweight of variable mass, to compensate for the offset of the center of gravity of the tubular part and the chassis relative to the axis B.

[0070] The jib 47, which carries all the welding elements, welding head 48, cables 49, filler metal reel and camera, is here independent of the elements supporting and rotating the tubular parts 41 and 42 to be welded. Preferably, spring boxes are associated with the lower roller turners 50 free to rotate.

[0071] The vibration resulting from the rotation of the tubular parts 41 and 42 is absorbed by a spring housing, for example sized to withstand up to 25 N. This spring housing also serves to balance the center of gravity of the assembly consisting of the tubular parts to be welded so as to keep the assembly stable during welding.

[0072] Thanks to the fixing of the rotating tubular parts 41 and 42 on frames 46 and 56 and to the spring box which absorbs the vibrations and repositions the center of gravity of the tubular parts 41 and 42, the automatic welding machine 40 makes it possible to weld tubular parts 41 and 42 along a welding line 55, in a large range of dimensions and curvatures of these parts.

[0073] It is noted that the frames 46 and 56 are compatible for different diameters of tubular parts and different angles of bends. Other frames cover other diameter ranges.

[0074] [Fig. 14] describes, in the form of a flowchart of a method 80, steps for implementing the device 40. This method 80 comprises, firstly, a step 81 for positioning the parts to be welded 41 and 42 in such a way that the lines tangent to their axes coincide at the level of the weld line 55, i.e. their contact line.

[0075] During a step 82, parts to be welded 41 and 42 are mechanically secured. Preferably, this securing is carried out by spot welding on the weld line 55, for example four spot welds spaced a quarter turn apart. The parts 41 and 42 thus form a rigid assembly.

[0076] During a step 83, the frames 46 and 56 are associated with the parts 41 and 42 in such a way that the weld line 55 is parallel to the external faces of the frames. The flexible pads are then applied to the walls of the parts 41 and 42 to hold them in position without deforming them.

[0077] During a step 84, the frames 46 and 56 are placed in the welding machine 40 in such a way that the circular welding line 55 is perpendicular to the axis of rotation B and centered on this axis of rotation B and that it is located opposite the future position of the welding head 48.

[0078] During a step 85, the chassis 46 is secured to the motorized plate 57 of the positioner 44 and the chassis 56 to the follower plate 58.

[0079] During a step 86, the welding assembly is lowered towards the welding line 55, via the bracket 47. Once the welding assembly is positioned in such a way that the welding head 48 is on the welding line 55, during a step 87, the welding assembly is fixed in position.

[0080] During a step 88, the parts 41 and 42 are rotated around the axis B and the welding is carried out with the welding head 48, under the control of the operator 13. Of course, during step 88, the parts 41 and 42 can make several turns around the axis B.

[0081] Once the welding of the parts 41 and 42 is completed, during a step 89, the plate 57 is separated from the chassis 46, before removing the chassis 46 and 56 and the parts 41 and 42 from the machine 40. Then, during a step 90, the chassis 46 and 56 are removed from the parts 41 and 42 welded together.

[0082] As a variant, only one of the tubular parts 41 or 42, non-cylindrical, is supported by a frame, respectively 46 or 56, the other part being supported in rotation by other means, for example idle rollers or at least one means of pinching without deformation mounted on the plate 58. This variant is particularly suitable for the case where this other tubular part is cylindrical. Statement of the invention

[0083] The present invention aims to overcome all or part of the drawbacks of the prior art. To this end, the present invention aims at a welding machine for welding two tubular parts, 41 and 42, mechanically integral and having a common circular section defining a welding line 55, which comprises: - a welding head 48, - at least one frame, 46 and / or 56, supporting one of the tubular parts, 41 and / or 42, during operation of the welding head, - a positioner 44 and 57 supporting, during operation of the welding head, each frame and each tubular part in which the common circular section is perpendicular to the axis of rotation B of the positioner and centered on this axis of rotation, and - a means 47 for moving the welding head configured to position the welding head in a fixed position opposite the welding line, during its operation.

[0084] Thus, at least one frame, 46 and / or 56, holds in position a tubular part to be welded, respectively 41 and 42, in such a way that the weld line is centered on the axis of rotation of the positioner 44 and in a plane perpendicular to this axis. The rotation of the positioner therefore causes this weld line 15 to turn on itself opposite the welding head 48. The quantity of metal deposited and the productivity of the machine 40 are thus increased.

[0085] In embodiments:

[0086] - a said frame 46 supports one of the tubular parts 41 during operation of the welding head, and - another said frame 56 supports the other of the tubular parts 42 during operation of the welding head.

[0087] In embodiments, at least one chassis, 46 or 56, carries flexible buffers 59 whose supports on the tubular part, respectively 41 and 42, are adjustable to pinch this tubular part without deforming it.

[0088] The tubular pieces 41 and 42 are thus firmly held in position by the frames 46 and 56, respectively. In addition, these adjustable buffers allow the same frame to be adapted to different diameters of tubular piece.

[0089] In embodiments, at least one chassis 46 comprises a rotating frame around an axis C linked to said chassis, this rotating frame being configured to take a variable position around the tubular part 41 and to pinch this tubular part without deforming it.

[0090] This frame allows the chassis 46 to be adapted to different curvatures of the tubular part 41.

[0091] In embodiments, at least one frame, 46 or 56, comprises a counterweight positioned and dimensioned so that the center of gravity of the tubular part, respectively 41 or 42, supported by this frame, and of this counterweight is located closer to the axis of rotation B than the center of gravity of said tubular part.

[0092] This reduces the effects of unbalance during the rotation of this tubular part.

[0093] In embodiments, the welding machine 40 comprises a bracket 47 projecting above the tubular parts, 41 and 42, this bracket 47 carrying the welding head 48 below it.

[0094] This bracket allows vertical movements of the welding head 48. It thus facilitates the positioning and removal of the welding head 48 opposite the welding line 55.

[0095] In embodiments, the welding machine 40 comprises a means for adjusting the height of the jib 47.

[0096] In embodiments, the positioner 44 comprises a motorized plate 57 on which one of the frames 46 is fixed supporting a said tubular part 41 during the operation of the welding head 48, the welding machine further comprising a follower plate 58 on which another said tubular part 42 is fixed during the operation of the welding head.

[0097] The tubular parts and each frame are thus supported at both ends of the machine. The circular follower plate 58 preferably rests on a free-roller welding rotator allowing, if necessary, the weight of all the tubular parts and frames to be taken up.

[0098] In embodiments, the welding machine 40 comprises a camera whose optical field covers the lower end of the welding head 48 and the welding zone, and a remote viewing screen 12 configured to display the images provided by the camera.

[0099] An operator can thus remotely operate the welding machine 40.

[0100] In embodiments, the welding machine 40 comprises at least one spring box comprising at least one roller 50 supporting at least one tubular part, 41 and / or 42, during operation of the welding head 48. This spring box makes it possible to dampen the vibrations due to the rotation of the positioner, the frames and the tubular parts.

Claims

Claims

1. Welding machine (40) for welding two tubular parts (41, 42), mechanically integral and having a common circular section defining a welding line (55), characterized in that it comprises: - a welding head (48), - at least one frame (46, 56) supporting one of the tubular parts (41, 42) during operation of the welding head, - a positioner (44, 57) supporting, during operation of the welding head, each frame and each tubular part in which the common circular section is perpendicular to the axis of rotation (B) of the positioner and centered on this axis of rotation, and - a means (47) for moving the welding head configured to position the welding head in a fixed position opposite the welding line, during its operation.

2. Welding machine (40) according to claim 1, wherein: - one said frame (46) supports one of the tubular pieces (41) during operation of the welding head, and - another said frame (56) supports the other of the tubular pieces (42) during operation of the welding head.

3. Welding machine (40) according to one of claims 1 or 2, in which at least one frame (46, 56) carries flexible pads (59) whose supports on the tubular part (41, 42) are adjustable to pinch this tubular part without deforming it.

4. Welding machine (40) according to one of claims 1 to 3, in which at least one chassis (46) comprises a frame rotating around an axis (C) linked to said chassis, this rotating frame being configured to take a variable position around the tubular part (41) and to pinch this tubular part without deforming it.

5. Welding machine (40) according to one of claims 1 to 4, in which at least one frame (46, 56) comprises a counterweight positioned and dimensioned so that the center of gravity of the tubular part (41, 42) supported by this frame and this counterweight is closer to the axis of rotation (B) than the center of gravity of said tubular part.

6. Welding machine (40) according to one of claims 1 to 5, which comprises a bracket (47) projecting above the tubular parts (41, 42), this jib carrying the welding head (48) below it.

7. Welding machine (40) according to claim 6, which comprises means for adjusting the height of the jib (47).

8. Welding machine (40) according to one of claims 1 to 7, in which the positioner (44) comprises a motorized plate (57) on which is fixed one of the frames (46) supporting a said tubular part (41) during the operation of the welding head (48), the welding machine further comprising a follower plate (58) on which is fixed another said tubular part (42) during the operation of the welding head.

9. Welding machine (40) according to one of claims 1 to 8, which comprises a camera whose optical field covers the lower end of the welding head (48) and the welding zone, and a remote viewing screen (12) configured to display the images provided by the camera.

10. Welding machine (40) according to one of claims 1 to 9, which comprises at least one spring box comprising at least one roller (50) supporting at least one tubular part (41, 42) during operation of the welding head (48).