The present invention relates to an orbital machining apparatus for tubular elements of the type specified in the preamble of the first claim.

In particular, the present invention relates to an apparatus suitable to allow the sectioning or welding, along the circumference, of a tubular element, such as a shell or a tube usually used for ventilation systems, flues or similar.

As is known, at the current state-of-the-art, the tubes forming the large or small ventilation pipes, are machined by means of orbital cutting systems.

Such machinery is the fruit of the evolution of the old systems for producing portions of tubing, comprising the cutting of metal sheets or foils, which are subsequently welded to create the tubular elements.

Whereas, orbital machinery allows machining to be carried out, mainly the cutting and marking, of elements, which are already tubular.

Systems of this type are, for example, marketed by manufacturers, such as Digisystem Sri and the Sitec Group.

For example, the system for producing flues with angles of 30°, 45° and 90° produced by Digisystem Sri comprises an apparatus for cutting at the first step, which has the basic features of the systems currently used for orbital cutting.

Such system comprises a spindle on which a tubular element can rest. As in other similar systems, the tubular element, constrained to the spindle, can rotate around the central axis thereof due to the aid of movement rollers, usually arranged below the pipe itself.

During the rotation, the tubular element interacts with the machining means, for example, a laser cutting system or other systems, which machine along the circumference defined by the section of the tubular element being processed.

Thus, the apparatus has cleaning means comprising an aspirator for scraps deriving from the machining arranged along the central axis of the spindle below the machining means. Thus, the cleaning means can travel integrally with the machining means so as to follow the movement of the machining means.

The systems made by the Sitec Group also have similar characteristics to the previous system.

In fact, the systems of the TO series are welding and cutting lathes for the circumferential, or orbital machining of various-sized shells. As regards the welding lathes, the structure is composed of an electro-welded and machined beam for machine tools and a motorised spindle managed by numerical control and devices for locking the piece.

The system of the TT series is also composed of a robust structure, an expander spindle for locking the tube, which carries out, on interpolation, the rotation and translation of the tube and a vertical slide for the cutting torch. It is possible to produce any importable figure by means of special software for managing the two interpolated axes. In this case, too, the system uses a suction apparatus arranged coaxially to the spindle, loosely constrained thereto, which is suitable to follow the machining means.

The described prior art comprises some important drawbacks.

In particular, all of the described machinery and systems have the important drawback of being relatively inefficient with large tubular elements. In fact, firstly, the suction apparatus does not allow the scraps deriving from the machining to be collected correctly because the suction mouth is too far from the cutting means.

It is no coincidence that extensions are often used, arranged between the suction mouth and the zone of the tube, subject to machining.

Furthermore, due to the large dimensions, the tubular elements may be subject to buckling and deformations far from the spindle gripping zone, compromising the machining. In this respect, for example, the cutting may be crooked and for such reason, the tubular element must be discarded.

In conclusion, a further drawback is given by the fact that the currently known systems do not allow machining to be carried out, such as cutting or welding on tubular elements, whose ends have already been machined, for example, comprising flanges or edgings.

In this situation, the technical task underlying the present invention is to produce an orbital machining apparatus for tubular elements capable of substantially overcoming at least part of the stated drawbacks.

In the scope of said technical task it is an important object of the invention to obtain an apparatus, which allows small or large tubular elements or tubes to be machined indifferently.

It is another important object of the invention to produce a machining apparatus, which ensures that the apparatus is always kept clean and free from scraps for any tubular element, i.e. also in the presence of tubes with large diameters, without needing to introduce extensions or other external elements, which weigh on machining times.

It is a further task of the invention to produce an apparatus, which enables the correct shape of the tubular element to be maintained, also far from the gripping zone, i.e. from the spindle, during the steps of machining so as to allow a quality machining.

In conclusion, it is a further object of the invention to produce a machining apparatus, which allows machining to be carried out not only on pipes with smooth walls, but also on tubes whose walls have already been machined and have, for example, flanges or edgings.

The technical task and specified objects are achieved with an orbital machining apparatus for tubular elements, as claimed in the accompanying claim 1.

Preferred technical solutions are highlighted in the dependent claims.

The features and advantages of the invention are clarified below by the detailed description of preferred embodiments of the invention, with reference to the accompanying drawings, wherein:

Fig. 1 shows part of an orbital machining apparatus for tubular elements according to the invention during the machining step of a tubular element;

Fig. 2 illustrates part of an orbital machining apparatus for tubular elements according to the invention prior to the step of stabilising a tubular element;

Fig. 3 is part of an orbital machining apparatus for tubular elements according to the invention devoid of the tubular element and configured for small tubular elements;

Fig. 4 represents part of an orbital machining apparatus for tubular elements according to the invention devoid of the tubular element and configured for large tubular elements;

Fig. 5 shows a front sectional view of an orbital machining apparatus for tubular elements according to the invention devoid of the tubular element and configured for large tubular elements;

Fig. 6 illustrates part of an orbital machining apparatus for tubular elements according to the invention devoid of the tubular element and comprising annular expanders and adapters for the machining of tubular elements with flanges and edgings; and

Fig. 7 is a front sectional view of an orbital machining apparatus for tubular elements according to the invention devoid of the tubular element and comprising annular expanders and adapters for the machining of tubular elements with flanges and edgings.

In the present document, the measures, values, shapes and geometric references (such as perpendicularity and parallelism), when associated with words like "almost" or other similar terms such as "approximately" or "substantially", are to be understood as except for measurement errors or inaccuracies owing to production and/or manufacturing errors and, above all, except for a slight divergence from the value, measure, shape, or geometric reference with which it is associated. For example, if such terms are associated with a value, they preferably indicate a divergence of not more than 10% of the same value.

Furthermore, when used, terms, such as“first”,“second”,“higher”,“lower”,“main� �� and“secondary” do not necessarily identify an order, relationship priority or relative position, but they can simply be used to distinguish different components more clearly from one another.

Unless otherwise stated, the measurements and data reported in this text shall be considered as performed in International Standard Atmosphere ICAO (ISO 2533: 1975).

With reference to the Figures, the orbital machining apparatus for tubular elements according to the invention is globally denoted with number 1.

Preferably, the apparatus 1 is an orbital cutting apparatus, however, it could also be an orbital welding apparatus or another type of apparatus using orbital-type machining. In particular, the apparatus 1 allows the machining of tubular elements 10.

The tubular elements 10 can be tubular sheets similar to those used for ventilation ducts or flues. Furthermore, the tubular elements 10 can be tubes having a smooth surface, without irregularities, or they can be tubes having raised portions, such as flanges or edgings.

The sections of the tubular elements 10 can be circular, oval, elliptical, rectangular or square.

The apparatus 1 preferably comprises coupling means 2, a support structure 3 and machining means 4.

The coupling means 2 are preferably suitable to allow the tubular element 10 to be constrained to the apparatus 1 so as to cause the tubular element 10 to be sufficiently locked firmly and allow the successive machining.

They can be external to the apparatus 1 , or they are preferably integrated therein and constrained to the support structure 3. Preferably, they are loosely constrained to the support structure 3 so as to be movable with respect to the latter along at least an axis.

Preferably, the coupling means 2 define a coupling plane 2a and a coupling direction

2b

Preferably, the coupling plane 2a is the portion of the coupling means 2 suitable to interface with a section of the tubular element 10. In fact, the latter is substantially a beam, which extends tubularly along a main direction of development, defining a plurality of successive ring sections.

The coupling direction 2b is a direction perpendicular to the coupling plane 2a. Preferably, the coupling means 2 are suitable to allow the tubular element 10 to be constrained, at the coupling plane 2a, so that the tubular element 10 is aligned with the coupling direction 2a, i.e. so that the main axis of development of the tubular element 10 is aligned with the coupling direction 2a.

Furthermore, the coupling means 2 are suitable to allow the tubular element 10 to rotate around the coupling direction 2a. Preferably, the rotation is carried out on command.

Thus, the coupling means 2 can comprise a spindle 20.

The spindle 20 is a spindle of the known type, suitable to allow the tubular element 10 to be removably constrained to the coupling means 2.

Preferably, the spindle 20 defines a discoid structure, extending in the support plane 2a and comprising a plurality of circular sectors 21.

The circular sectors 21 are disc portions, which can be moved away from, or towards the centre defined by the disc, on command. Preferably, the centre of the disc is arranged on the coupling direction 2b and the circular sectors 21 move towards and away from the coupling direction 2b, on command.

The spindle 20 further includes a plurality of grains 22. The grains 22 are concentric projections centred with respect to the coupling direction 2b suitable to allow the tubular element 10 to be inserted between one grain 22 and the next.

Thus, such grains 22 extend between one circular sector 21 and the other. When the spindle 20 is in the rest configuration, the circular sectors 21 are mutually adjacent and the grains 22 define continuous concentric rings on the coupling plane 2a.

Instead, when the spindle 20 is in the operational configuration, the circular sectors 21 are mutually spaced apart and the grains 22 define discontinuous concentric rings on the coupling plane 2a.

When the spindle 20 is in the operational configuration, the grains 22 widen or tighten so as to constrain the tubular element 10 by friction.

As said, such types of coupling means 2 are known at the current state-of-the- art. The support structure 3 preferably extends parallel to the coupling direction 2b and defines a support direction 3a.

The support direction 3a is substantially parallel to the coupling direction 2b and, consequently, it is substantially parallel to the tubular element 10 when the latter is constrained to the coupling means 2.

Preferably, the support structure 3 is also integral with at least part of the coupling means 2. Preferably, the support structure 3 defines a frame arranged, at least in part, around or at the side or above the ground, of the coupling means 2.

Thus, the support structure 3 can define an open frame, wherein the tubular element 10 is always accessible to a user, or it can define a re-sealable frame to make the tubular element 10 inaccessible when the latter is being machined.

In any case, the support structure 3 is suitable to sustain at least the machining means 4. In particular, the support structure 3 comprises movement means 8. Preferably, the movement means 8 are suitable to loosely constrain external elements, such as, for example, the machining means 4. The movement means 8 can include, for example, movement tracks 80.

Preferably, the movement tracks 8 are aligned, or parallel to the support direction 3a so as to allow at least the movement of the external elements along the support direction 3a.

Preferably, the machining means 4 define a machining direction 4a.

The machining direction 4a is the direction along which the machining means 4 interact with the tubular element 10. As said, preferably, the apparatus 1 is of the orbital type and, thus, the machining means 4 are suitable to carry out machining along the outer surface of the tubular element.

Thus, the machining direction 4a is preferably perpendicular to the coupling direction 2b and parallel to the coupling plane 2a.

Furthermore, the machining means 4 are loosely constrained to the support structure 3. In particular, the machining means 4 are at least suitable to travel along the support direction 3a so as to move towards or away from the coupling means 2. Thus, the machining means 4 can comprise a first carriage 40.

Preferably, the first carriage 40 is loosely constrained to a movement track 80 so as to be free to move along the support direction 3a.

Thus, the first carriage 40 and the movement track 80 can be mutually constrained by mechanisms known at the current state-of-the-art and already commonly used in orbital machining apparatus for tubular elements 10.

Additionally, the machining means 4 are suitable to travel along the machining direction 4a so as to move towards or away from the tubular element 10.

Thus, preferably, the machining means 4 also comprise a machining head 41. Preferably, the machining head 41 is a head suitable to allow the cutting of tubular elements 10. For example, the machining head 41 can comprise a blade, or a laser head or other types of technologies, which allow the cutting or marking sheets, for example, metal sheets.

Flowever, the machining head 41 could comprise a welding head or other instruments for machining tubular elements 10.

Preferably, the welding head 41 is loosely constrained to the first carriage 40 so as to be able to at least travel along the machining direction 4a. Mechanisms of this type can include, for example, linear actuators of the mechanical or pneumatic type and they are known at the current state-of-the-art. Preferably, the apparatus 1 also comprises suction means 5.

The suction means 5 are suitable to suck up scraps deriving from the machining of the tubular element 10. Thus, preferably, they are suitable to move integrally with the machining means 4.

The machining means 4 usually being arranged above the tubular element 10, with respect to the ground, the suction means 5 are suitable to be arranged below the machining means 4 and the zone of the tubular element 10 being machined.

Substantially, preferably, the suction means 5 are suitable to be positioned within the volume enclosed by the tubular element 10.

Advantageously, the suction means 5 are separate from the coupling means 2. In fact, they are loosely constrained to the support structure 3 so as to travel along the support direction 3a integrally with the machining means 4. Thus, preferably, the suction means 5 comprise a second carriage 50.

Substantially, the second carriage 50 can be similar to the first carriage 40. Thus, it can be loosely constrained to a movement track 80 so as to be freely movable along the support direction 3a.

Furthermore, the suction means 5 are suitable to travel along the machining direction 4a so as to maintain the mutual distance between the suction means 5 and the machining means 4 below a predetermined threshold value.

Substantially, the suction means 5 can follow the machining means 4 along at least two directions 3a, 4a so as to allow an optimum suction of the scraps and independently of the size of the tubular element 10.

Thus, the suction means 5 comprise a suction rod 51.

Preferably, the suction rod 51 is loosely constrained to the second carriage 50 so as to be parallel to the support direction 3a and to the coupling direction 2a. Furthermore, the suction rod 51 can travel along the machining direction 4a, for example, by means of a linear actuator or similar devices already known in the current state-of-the-art.

Opportunely, the suction means 5 are spaced apart from the coupling means 2 so that the suction means 5 can access the tubular element 10, starting from the opposite end thereof, i.e. starting from the free end of the tubular element 10.

The apparatus 1 also comprises main sustaining means 6.

The main sustaining means 6 are suitable to sustain the tubular element 10 preferably below the tubular element 10 itself with respect to the ground. Substantially, the tubular element 10 preferably rests, by gravity, on the main sustaining means 6 along the length thereof so as to maintain the shape along the coupling direction 2b and not deform on bending.

The main sustaining means 6 also define a first sustaining direction 6a.

Preferably, the first sustaining direction 6a is perpendicular to the coupling direction 2b and parallel to the coupling plane 2a.

The first sustaining direction 6a is substantially the direction along which the main sustaining means 6 interact with the tubular element 10. Thus, the latter is resting along the first sustaining direction 6a.

Preferably, the main sustaining means 6 extend integrally with the support structure 3 along the support direction 3a.

Additionally, the main sustaining means 6 are suitable to travel, at least partially, along the first sustaining direction 6a so as to move towards or away from the coupling direction 2b.

In detail, the main sustaining means 6 comprise main rollers 60.

The main rollers 60 are cylindrical elements extending along the support direction 3a and suitable to allow the resting of the tubular element 10. Opportunely, the first sustaining means 6a comprise at least two main rollers 60 arranged below the coupling direction 2b, with respect to the ground, so as to allow the resting of the tubular element 10.

Preferably, the main rollers 60 can be moved along the first sustaining direction 6a slanted to the ground. For example, the first sustaining direction 6a defined by the main rollers 60 can be slanted by 45° degrees to the ground.

Such inclination can be fixed, or the main rollers 60 can also include mechanisms for varying the inclination to the ground. Preferably, the sustaining direction 6a is oblique and fixed.

The main sustaining means 6 further comprise at least a secondary roller 61.

The secondary roller 61 is independent of the main rollers 60.

Preferably, it is arranged between the main rollers 60 and defines a first sustaining direction 6a perpendicular to the ground.

Travelling along the first sustaining direction 6a, the secondary rollers 61 allows the arc of curvature made with the main rollers 60 to be varied so as to allow the resting of tubular elements 10 with varying diameters.

In fact, the support provided by the secondary roller 61 is very important, especially for tubular elements 10 with large diameters.

Preferably, the secondary roller 61 is arranged, in use, between the main rollers 60. The main sustaining means 6 can further comprise third rollers 62.

Preferably, the third rollers 62 define a first sustaining direction 6a parallel to the ground.

Preferably, in a configuration of use, the third rollers 62 are arranged along the sides of the tubular element 10 so as to lock it firmly and maintain the shape of the tubular element 10 without deformations.

Preferably, the third rollers 62 are, like the main rollers 60, two in number and arranged substantially specularly to the coupling direction 2b.

Preferably, the third rollers 62 are also suitable to travel along a direction perpendicular to the ground.

In this case, too, the third rollers 62 allow different curvatures to be made with the main rollers 60 and the secondary roller 61 so as to be able to house tubular elements 10 with varying dimensions.

Thus, the main sustaining means 6 substantially make a clamp suitable to sustain and lock the tubular element 10.

In detail, each of the rollers 60, 61 , 62 is free to rotate around the axis thereof. In fact, they are suitable to allow the resting of the tubular element 10 and to rotate integrally with the tubular element 10 when the tubular element is rotated by the coupling means 2.

The apparatus 1 additionally comprises secondary sustaining means 7.

The secondary sustaining means 7 are suitable to sustain at least part of the tubular element 10. However, unlike the main sustaining means 6, the secondary sustaining means 7 are suitable to be inserted within the volume enclosed by the tubular element 10.

Thus, the secondary sustaining means 7 define a second sustaining direction 7a. Preferably, the second sustaining direction 7a is perpendicular to the coupling direction 2b and parallel to the coupling plane 2a.

It is the direction along which the secondary sustaining means 7 interact with part of the tubular element 10.

Advantageously, the secondary sustaining means 7 are separate from the main sustaining means 6 and spaced apart therefrom.

In particular, the secondary sustaining means 7 are preferably arranged above the coupling direction 2b, with respect to the ground.

Furthermore, the secondary sustaining means 7 are loosely constrained to the support structure 3 so as to travel along the support direction 3a so as to sustain at least part of the tubular element 10 when moved towards the coupling means 2. In fact, as with the suction means 5, the secondary sustaining means 7 are spaced apart from the coupling means 2 so as to be able to access the tubular element 10, starting from the end opposite the coupling means 2 thereof, i.e. starting from the free end of the tubular element 10.

In fact, the secondary sustaining means 7 could be moved integrally with the suction means 5.

In general, the secondary sustaining means 7 are suitable to travel along the second sustaining direction 7a so as to move away from or towards the coupling direction 2b.

In this way, the secondary sustaining means 7, together with the main sustaining means 6, allow the tubular element 10, inserted in the apparatus 1 , to maintain its shape, also when it has large diameters and can be deformed more easily.

Preferably, the secondary sustaining means 7 comprise a third carriage 70.

Substantially, the third carriage 70 can be similar to the first carriage 40 and/or to the second carriage 5. Thus, it can be loosely constrained to a movement track 80 so as to be freely movable along the support direction 3a.

Thus, additionally, the secondary sustaining means 7 comprise at least an auxiliary roller 71. In a preferred configuration, the secondary sustaining means 7 comprise two auxiliary rollers 71 . The auxiliary rollers 71 are of the same type as the rollers 60, 61 , 62 and they are preferably loosely constrained to the third carriage 70 so as to be parallel to the support direction 3a and to the coupling direction 2a.

Furthermore, the auxiliary roller or rollers 71 can travel along the second sustaining direction 7a, for example, by means of a linear actuator or similar devices already known in the current state-of-the-art.

As regards the movement of each of the machining means 4, suction means 5, main sustaining means 6 and secondary sustaining means 7, the movement means 8 can comprise a plurality of motors 81.

All types of motors 81 can be used depending on the needs.

For example, the drive motors 81 of the machining means 4 can be similar to those present on common overhead cranes and suitable to allow the movement of the machining means 4 along the movement tracks 80.

The same suction means 5 and the secondary sustaining means 7 can be loosely constrained, at least in part, to the support structure 3 by means of movement tracks 80 and actuated, to guarantee the translation thereof along the support direction 3a, by motors 81 similar to those used for the machining means 4.

Furthermore, as stated previously, the suction means 5 and the secondary sustaining means 7 can be moved independently or integrally.

Whereas, the motors 81 suitable to move the main sustaining means 6 can comprise linear actuators arranged at the ends of the rollers 60, 61 , 62.

In any case, the movement means 8 are of the common type, already used in orbital machining apparatus, including the machinery stated in the prior art.

Thus, the motors 81 can be mechanical, electronic, mechatronic, hydraulic or other. In general, each motor 81 is nonetheless suitable to be controlled by electronic means.

Furthermore, the movement means 8 could also be operatively connected to the coupling means 2. In fact, the coupling means 2 could be fixed to the support structure 3, or they could partly travel along the coupling direction 2b.

In particular, preferably the coupling plane 2a can travel along the coupling direction 2b with respect to the support means 3 so as to be able to potentially move the coupling means 2 away from or towards the main sustaining means 6.

Preferably, the movement means 8 are operatively connected to control means 9. The control means 9 are suitable to interface with each of the motors 81 included in the movement means 5. In particular, the control means 9 are suitable to command the movement means 5 and, thus, to command the machining means 4, the suction means 5, the main sustaining means 6 and the secondary sustaining means 7.

The control means 9 can comprise a processor 90 and a control terminal 91.

The processor 90 can include the set of electrical connections to the motors 81 and the processing unit, which communicates the activation and deactivation signals for each of the means 2, 3, 4, 5, 6, 7, 8 present in the apparatus 1 .

Whereas, the control terminal 91 is suitable to allow a user to communicate with the processor 90 so as to give the commands to each of the means 2, 3, 4, 5, 6, 7, 8.

In fact, each of the stated means 2, 3, 4, 5, 6, 7, 8 can be commanded to guarantee the complete functionality and efficiency of the apparatus 1 on tubular elements 10 with different dimensions.

Thus, the processor 90 can be a numerical control machine of the known type and the control terminal 91 can comprise a computer or other means, which allow the user to command the apparatus 1 .

The user can give the commands relating to the positioning of the tubular element 10 regarding, for example, the diameter of the tubular element 10 actuating the sustaining means 6, 7 and constraining the tubular element 2 to the coupling means 2.

Furthermore, he/she can give commands for the machining of the tubular element 10 moving the coupling means 2 around the coupling direction 2a and opportunely activating and moving the machining means 4 and the suction means 5.

As it is described, the apparatus is suitable to allow the machining of tubular elements 10, preferably including a smooth and regular surface.

However, the apparatus 1 can also allow the machining of tubular elements 10 comprising flanges and edgings and thus defining an irregular outer surface.

Advantageously, the apparatus 1 can comprise annular expanders 64.

The annular expanders 64 are removably constrained to at least the main rollers 60 so as to locally increase the diameter of the main rollers 60, as shown in Fig. 5.

In particular, the annular expanders 64 are suitable to allow the tubular element 10 to rest solely on the same annular expanders 64.

In this way, any edgings or flanges can be housed in the cavities made between the adjacent annular expanders 64.

Thus, the annular expanders 64 can be openable so as to be easily mounted and dismantled from the rollers. For example, the annular expanders 64 can comprise two portions, which can be mutually constrained by means of mechanical joints, such as screws, in order to make the annular expander 64.

To achieve the same object, the coupling means 2 can comprise adapters 23.

The adapters 23 are cores, which can be mounted, for example, radially, at the ribbing 22 of the spindle so as to create a circular structure around which it is possible to constrain the tubular element 10 by interlocking without needing to introduce the edgings of the same tubular element 10 inside the ribbing 22 of the spindle 20.

In this way, when the circular sectors 21 of the spindle expand, the adapters 23 expand with the spindle constraining the tubular element 10. Therefore, the adapters 23 allow tubular elements 10, flanged or comprising edgings, to be removably constrained to the coupling means 2.

Opportunely, at least an adapter 23 for each circular sector 21 is removably constrained. The connection can be made by interlocking or, preferably, by means of mechanical joints, such as screws.

The operation of the apparatus 1 described previously in structural terms is as follows.

The user can rest a tubular element 10 on the main sustaining means 6 and adjust each of the rollers 60, 61 , 62 using the control means 9 so as to create the curvature necessary for the stable housing of the tubular element 10.

After carrying out such process, the secondary sustaining means 7 are inserted inside the tubular element 10 and the spindle 20 locks the tubular element. The secondary sustaining means 7 are also commanded using the command means 9 so as to be compatible with the dimensions of the tubular element 10. The latter rests the inner surface thereof on the secondary sustaining means 7 so as not to deform along the coupling direction 2a due to undesired bending.

After setting all of the coupling means 2 are set, it is possible to command the machining means 4 to start the machining of the tubular element 10. The suction means follow the machining means 4 at a predetermined distance being free with respect to the coupling means 2 and inserted within the volume defined by the tubular element 10 starting from the free end. The invention comprises a new process for machining tubular elements 10. In particular, the process comprises at least an assembling step, a positioning step and a machining step.

In the assembling step, a tubular element 10 is arranged on the main sustaining means 6 and it is constrained to the coupling means 2. In particular, preferably, the tubular element 10 is centred on the coupling direction 2b and the main sustaining means 6 are moved so that at least the rollers 60 adhere to the outer surface of the tubular element 10.

Furthermore, if the tubular element 10 is large, the secondary roller 61 can be positioned 61 adjacent to the tubular element 10.

Whereas, the third rollers 62, if present, can be arranged symmetrically along the sides of the tubular element 10 and then they can also be moved along the first sustaining direction 6a, which, in this case, is parallel to the ground.

Therefore, the tubular element 10 is further supported by the main sustaining means to avoid deformations with respect to the original profile of the same tubular element 10.

During the positioning step, the machining means 4 are positioned, preferably by the movement means 8, at a fixed point relative to the support means 3 so that the machining means 4, opportunely the machining head 41 , are arranged in the vicinity of the outer surface of the tubular element 10.

Thus, in the machining step, the machining means 4 are activated and, at the same time, the tubular element 10 is caused to rotate around the coupling direction 2a by the coupling means 2.

All of the movements carried out during the assembling and machining steps can be configured beforehand or during the machining by the control means 9. In particular, it is possible to set all of the machining parameters by means of the control terminal 91 . This activity can be carried out beforehand or it can be carried out during the machining.

Therefore, preferably, the machining process can comprise a further programming step.

The programming step can be carried out before each other step, it can be carried out only once, or it can be carried out whenever it is considered necessary. Furthermore, the programming step can also be carried out between the assembling step and the machining step or at other times.

In the programming step, it is possible, for example, to set and record all of the mutual distances between the means 2, 3, 4, 5, 6, 7, 8 on the internal memory of the processor 90, so as to create a univocal reference system, for example, which is fixed with respect to the support means 3.

Furthermore, in the programming step, using the control means 9, it is possible to insert the diameter characteristic of the tubular element 10 being machined so that each of the means 2, 4, 5, 6, 7, 8 can automatically be arranged in the correct position.

Such operations are already commonly carried out in the systems of the prior art. Flowever, advantageously, the apparatus 1 allows the threshold value referring to the mutual distance between the suction means 5 and the machining means 4 to be defined in the programming step.

In this way, depending on the different thicknesses of the tubular elements 10, it is possible to maintain great efficiency in terms of cleaning the scraps deriving from the machining step; in fact, preferably, the suction means 5 and the machining means 4 move integrally so as to keep the mutual distance thereof below the threshold value set during the machining step.

Advantageously, the machining process can also comprise a stabilising step.

- The stabilising step can be carried out, for example, during the assembling step so as to prepare the tubular element 10 to interact correctly with the coupling means 2 and the machining means 4. Thus, opportunely, the assembling step is carried out, in particular, before the tubular element 10 is constrained to the coupling means 2. In particular, in the stabilising step, the secondary sustaining means 7 are preferably inserted within the tubular element 10 and moved along the second sustaining direction 7a so as to sustain the tubular element 10, avoiding undesired deformations of the latter.

Substantially, the main sustaining means 6 and the secondary sustaining means 7 define a circumference passing through at least the rollers 60, 71 , which coincides with the profile of the tubular element 10 if the latter is substantially hollow and cylindrical.

Thus, advantageously, also for large tubular elements 10, in terms of diameter, it is possible to carry out machining, avoiding the common deformations occurring at the free end of the tubular element 10, i.e. the end far from the coupling means 2. Additionally, the secondary sustaining means 7 significantly facilitate the locking by the coupling means 2 as interventions by an external operator are not needed to align the section of the tubular element 10 with the coupling plane 2a.

All of the described steps are functional for smooth tubular elements 10, however, they might not work with tubular elements 10 comprising flanges or edgings.

Preferably, for the latter, the process comprises a further conversion step.

In the conversion step, at least the main sustaining means 6 are provided with annular expanders 64. In particular, preferably, at least two annular expanders 64 are applied on each main roller 60 so that only the annular expanders 64 sustain the tubular element 10. Furthermore, the annular expanders 64 are mutually spaced apart on the same main roller 60 so that the edging portions and flanges can be arranged in the cavities made between the annular expanders 64 or after the annular expanders 64.

Thus, the annular expanders 64 can also be arranged on the secondary rollers 61 and on the third rollers 62, preferably, in pairs.

Additionally or alternatively, the process can comprise an adjustment step, wherein it is possible to arrange the adapters 23 on the coupling surface 2a at the ribbing 22. In this way, if the tubular element 10 has flanges or edgings at the end to be arranged in contact with the coupling means 2, it is possible to constrain the tubular element 10 by means of such adapters 23.

In order to allow the coupling to the tubular element 10 in a compliant position, the coupling plane 2a is spaced apart from the main sustaining means 6 by moving the coupling means 2 along the coupling direction 2b.

A compliant position means a position wherein the difference in positioning of the tubular element 10 is taken into account due to the fact that the latter is no longer inserted between the ribbing 22, but arranged above them. Therefore, for example, the coupling plane 2a could be retracted with respect to the main sustaining means 6 along the coupling direction 2b by a distance equal to the depth of the ribbing 22. Thus, the adapters 23 are expanded in the assembling step. Therefore, the adjustment step and/or the conversion step are preferably carried out before the assembling step to prepare the apparatus for tubular elements 10 with flanges or edgings.

The orbital machining apparatus for tubular elements 1 according to the invention offers important advantages.

In fact, the apparatus 1 allows large and small tubular elements to be machined indifferently. In fact, the main sustaining means 6 and the secondary sustaining means 7 allow the shape of the tubular elements 10 to be maintained, avoiding deformations which may occur at the free end of the same, i.e. in the portion in which the same is not constrained by the coupling means 2a.

Furthermore, the configuration of the suction means 5 allows the apparatus to be adapted to large tubular elements 10, preventing the apparatus from being dirtied with scraps, or avoiding having to install extensions with the obvious burden on machining times and machining costs of the tubular element stated above.

In addition to the advantages stated previously, the apparatus 1 allows smooth tubular elements 10 and tubular elements 10 with flanges or edgings to be machined indifferently due to the configuration of the annular expanders 64 and/or the adapters 23.

The latter advantage is extremely important, especially if we consider that machining can often be requested during execution, i.e. on pieces and tubular elements 10, which are ready for installation and thus already provided with flanges and edgings. The invention is subject to variations falling within the scope of the inventive concept defined by the claims.

In such scope, all details can be replaced by equivalent elements and any materials, shapes and sizes can be used.