EP2982455A1

EP2982455A1 - Apparatus and method for bending tubular components

Info

Publication number: EP2982455A1
Application number: EP15179891.5A
Authority: EP
Inventors: Armando Scaramuzza
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-08-05
Filing date: 2015-08-05
Publication date: 2016-02-10

Abstract

An apparatus (100) for bending tubular components (T) comprises a support base (101), first and second retaining means (1, 2) of the tubular component (T) capable of retaining the tubular component (T). The first retaining means (1) are supported on the base (101). The apparatus further comprises a rotary support portion (102) connected to the base (101) in a rotary manner about a bending axis (Z). The second retaining means (2) are supported on the rotary support portion (102). The apparatus (100) further comprises an articulated core(3) which may be inserted inside the tubular component (T), may be bent at least about a bending axis (Z) and may move with respect to the base (101) along rectilinear guide means (4) in a controlled manner coordinated with a movement of rotation of the rotary support portion (102). The second retaining means (2) comprise an abutment edge (20) capable of abutting against a bent end (T') of the tubular component (T) so as to prevent axial movements of the tubular component (T) extracting it from the second retaining means (2).

Description

The invention relates to an apparatus for bending tubular components, of the type comprising retaining means of the tubular component and a rotary support portion by means of which an end of the tubular component is rotated.
In the construction of industrial plants of various types, it is necessary to provide for the adoption of rigid tubular components for the transport of liquid or gaseous products under pressure. In many cases, normally in accordance with the capacities and the operating conditions of the plant, and therefore the dimensions of the component, it is not possible to carry out the bending operation during the installation and positioning steps and therefore it is necessary to provide the tubular connections which it is necessary to use beforehand.
To that end, it is known to use machines for bending tubular components which allow the production of connection elements according to the angle desired. For example, the American patent application US 2006/0201219 describes an apparatus for bending bar-like and tubular components which comprises a first fixed portion and a second movable portion, which is in particular rotatable with respect to the first portion. Each of the portions comprises means for gripping the tube which are produced by means of vices which press on respective ends of the tube itself.
The movable portion, once the tube has been blocked, rotates with respect to the fixed portion and the tube is bent by abutting a curved surface, having a shape complementary to the curvature which it is desirable to produce.
A main disadvantage of that machine as well as other known machines, such as, for example, the ones described in DE 10 2011 000845 , US 6,155,091 , US 2004/011106 , US 2006/053853 , US 5,937,686 , is connected with the fact that the portions on which the gripping action is carried out normally have to be discarded, being readily deformed or even destroyed at the surface during the bending step.
It is therefore necessary to make allowance for a waste of material which, in known machines, is not negligible, with a consequent increase in costs.
An additional problem is that of the difficulties connected with the construction of tubular elements which are bent at radii of curvature which are small in the case of relatively small thicknesses and high diameters.
In fact, it is evident that, when the diameter of the tube increases and the thickness decreases, the mechanical structure is more readily subjected to local deformations which are not controlled during the curvature of the tube and which make it necessary to restrain the radius of curvature.
On the other hand, by reducing the radius of curvature it would be possible to reduce the volume required for the installation of the tubular elements, in particular when they have to extend along a wall in the region of a corner thereof. Furthermore, in general, the deformations to which the material may be subjected during the bending operation may lead to surface irregularities with resultant losses of charge which are undesirable in the present applications.
Therefore, those problems are perceived more greatly in the case of materials which cannot be heated without losing some of the mechanical characteristics thereof, as in the case of stainless steel.
The technical problem addressed by the present invention is therefore to provide an apparatus for bending tubular components which is structurally and functionally configured to overcome all the disadvantages set out with reference to the cited prior art.
That problem is solved by means of an apparatus for bending tubular components according to claim 1 and by a method for bending tubular components according to claim 9.
Preferred features of the invention are defined in the dependent claims.
The invention and the method according to the present invention allow bending of tubular components with minimum wastage of material and are found to be particularly suitable for producing radii of curvature which are relatively small even in the case of components having large dimensions and/or small thicknesses. This also allows the bending operation to be carried out with small radii of curvature in the cold state, thereby allowing processing even of those materials which cannot be subjected to thermal variations during the processing thereof.
In addition, the invention and the method according to the present invention allow minimization of the presence of uncontrolled local deformations at the surface of the tubular component, thereby preventing to the greatest possible extent possible surface irregularities.
The features and additional advantages of the invention will be better appreciated from the following detailed description of a preferred but non-exclusive embodiment thereof which is illustrated by way of non-limiting example with reference to the appended drawings, in which:

Figure 1 is a perspective view of the apparatus for bending tubular components according to the present invention;
Figure 2 is a plan view of the apparatus for bending tubular components of Figure 1 ;
Figure 3 is a partial perspective view of retaining means and an articulated core of the apparatus for bending tubular components of Figure 1;
Figure 4 is a partial, detailed perspective view of the retaining means and the articulated core of Figure 3 with a relevant tubular component;
Figure 5 is a detailed perspective view of the retaining means of Figure 3;
Figure 6 is a perspective view in accordance with a different perspective of the apparatus for bending tubular components according to the present invention in a different operating configuration;
Figures 7 and 8 are perspective views of the articulated core of the apparatus according to the present invention according to two operating configurations;
Figure 9 is a perspective view of the apparatus for bending tubular components according to the present invention, in which panels have been removed for illustrating the internal components thereof;
Figures 10 and 11 are additional detailed perspective views in accordance with different perspectives of the retaining means of Figure 3;
Figure 12 is a plan view of a second embodiment of the apparatus for bending tubular components according to the present invention;
Figure 13 is a side view of the apparatus for bending tubular components of Figure 12;
Figure 14 is a perspective view of the apparatus for bending tubular components of Figure 12 in a different operating configuration; and
Figure 15 is a perspective view in accordance with a different perspective of the apparatus for bending tubular components in the operating configuration of Figure 14.

Initially with reference to Figure 1, an apparatus for bending tubular components T is generally designated 100.
The apparatus 100 comprises a support base 101 which is produced in accordance with a preferred embodiment by means of a frame and a series of removable panels. A rotary support portion 102 is connected to the base 101 in a rotary manner so as to be able to rotate with respect to the base 101 according to methods which will be described in greater detail below.
The rotation movement takes place about a bending axis Z which corresponds to the axis about which the tubular component T is bent. The movement of the rotary portion 102 takes place by means of suitable movement means 5.
In the present embodiment, the movement means 5 which are illustrated in detail in Figure 9 comprise an actuator 50 which linearly moves a sliding member 51 which can slide on guides 52. The sliding member 51 is connected to chains 52 which are connected to the rotary portion 102 at an opposite end to the portion, preferably at pulleys 54 which are fixedly joined to the portion 102 itself.
The actuator 50 is arranged in such a manner that the extraction of the relevant rod 55 produces a rotation of the pulleys 54 and, consequently, the portion 102, about the axis Z.
Again with reference to Figure 1, the apparatus 100 for bending tubular components T according to the present invention further comprises first and second retaining means 1, 2 for the tubular component T which are fixedly joined to the base 101 and the rotary portion 102, respectively. More specifically, the retaining means 1 and 2 are capable of retaining respective ends of the tubular component T.
With reference to Figure 4, according to a preferred embodiment, the first retaining means 1 are constructed by means of a pair of jaws 11, 12 which comprise respective opposing surfaces which are formed in a complementary manner with respect to the tube which it is necessary to retain. Preferably, the first jaw 11 is fixed to the base 101 by means of support planes 111, 112, 113 which can slide relative to each other on guides and which allow the movement thereof within a plane.
However, the second jaw 12 is movable on a linear guide 121 which allows the movement of the jaw 12 in a direction parallel with the longitudinal axis of the longitudinal component portion T which is retained by the jaws 11 and 12.
Preferably, the linear guide 121 is supported in a sliding manner by means of an articulated mechanism 13 which is capable of moving the linear guide 121 and the second jaw 12 towards/away from the first jaw 11. In other words, that articulated mechanism 13 allows the jaws 11 and 12 to close, by moving them together and thereby retaining the tubular component T.
Preferably, the articulated mechanism 13 is of the type with a toggle and comprises a series of pairs of connecting rods 131 and 132. According to a preferred embodiment, a first series of connecting rods 131 has an end which is rotatably connected to the base and a second end which is rotatably connected to a first end of the respective connecting rod 132 of the second series. However, the second end of the connecting rods 132 is connected in a rotatable manner to a support element 133 on which the linear guide 121 is supported by means of additional guides 134.
Still in accordance with a preferred embodiment, the support element 133 is further able to slide on the base 101 by means of guides 135 which are orientated in the approach/withdrawal direction with respect to the first jaw 11. Therefore, the rotation of the connecting rods 131, for example, controlled by means of an actuator 136, allows the support element 133 to be approached/withdrawn, as well as the linear guide 121 and the second jaw 12 with respect to the first jaw 11, thereby bringing about the closure/opening thereof.
That embodiment advantageously allows effective retention of the tubular component T while allowing the translation movement of the retaining means 1 in the axial direction X. As will be seen in greater detail below, that characteristic allows the tubular component T to be accompanied during the bending steps.
It should further be observed that the jaws 11 and 12 are fixed in a removable manner so as to be able to change them in accordance with the diameter of the tubular component T to be bent.
Preferably, in order to provide greater stability for the first retaining means 1, there is provided a reinforcement rod 14 which connects the articulated mechanism 13 to a pin which cannot be seen in the Figures and which is coaxial with the axis Z.
Then with reference to Figure 2, the second retaining means 2 preferably also comprise a pair of jaws 21 and 22 which can be moved together/apart in a direction perpendicular to the axis of the portion of the tubular component T which is retained by the second retaining means 2.
It is evident that, as illustrated in Figure 2, that direction corresponds to the one of the first retaining means 1, as well as the general axial development direction of the component T as long as this is rectilinear.
Preferably, the second retaining means 2 further comprise a movement device 23 for the second jaw 22, preferably formed by a linear actuator 230, the rod 231 of which allows the linear movement of the second jaw in the direction which is described above and illustrated in the Figures. According to a preferred embodiment, the movement device 23 is fixedly joined to the rotary portion 102 and therefore also allows the tubular component T to be retained during the rotation thereof.
In order to also provide greater stability for the second retaining means 2, the apparatus 100 preferably comprises a reinforcement rod 24 which extends between the movement device 23 and the pin which is coaxial with the axis Z.
Then with reference to Figure 4, the second retaining means 2 further comprise an abutment edge 20 which is preferably produced at the jaws 21 and 22. As illustrated in the Figures, the edge 20 is capable of abutting a bent edge T' of the tubular component T, thereby preventing the translation movement thereof along the axis X in the extraction direction, that is to say, withdrawal movement, of the component T away from the jaw or more generally from the retaining means.
To that end, according to a preferred embodiment, the abutment edge 20 defines an opening through which the tubular component T can pass in the region of the nominal portion thereof, that is to say, the portion which is not subjected to bending. At the same time, the opening defined by the abutment edge 20 does not have sufficient dimensions to allow the passage of the bent end T', thereby bringing about the abutment between the end and the abutment edge 20.
Preferably, the bent end T' extends radially towards the outer side of the tubular component T.
In this manner, when the jaws 21 and 22 retain the tubular component T, preventing movements in directions normal to the axis X, the tubular component T is retained in that direction, at least in one sense, by means of abutment with the edge 20.
That characteristic is found to be particularly advantageous because it allows the component T to be advanced, or more specifically the bent end T' thereof, along a bending path, that is to say, in rotation about the axis Z, without needing a high clamping force on the jaws 21 and 22.
In this manner, it is possible to prevent the end portions of the tubular component T from being subjected to deformations as a result of the clamping force of the jaws and having to be removed for the use of the tubular component once it is bent. In fact, it will be sufficient to dispose of a small portion thereof corresponding to the bent zone.
It may also be noted that the apparatus according to the present invention allows production of the bent end T' and blocking of the tubular component T, preventing movements in directions normal to the axis X in both senses, with methods which will be described in greater detail below. Then with reference to Figure 5, the first jaw 21 of the second retaining means 2 preferably has a portion 211 extending in a rectilinear manner and a portion 212 extending in a curved manner. In particular, the portion 212 extending in a curved manner extends about the axis Z in such a manner that, during rotation of the rotary portion 102, the first jaw 21 provides support for the tubular component T at the bend, as illustrated in Figure 6.
Now with reference to Figure 3, the apparatus 100 according to the present invention further comprises an articulated core 3 which can be inserted inside the tubular component T. The core 3 is associated in a removable manner with rectilinear guide means 4, so as to be able to be replaced in accordance with the inner diameter of the tubular component T.
As illustrated in Figure 4, the core 3 has such dimensions as to be able to be received with a given play inside the tubular component T. In other words, it will be possible to insert and remove the core in/from the tubular component without there being any interference between the components, but at the same time the core 3 will prevent excessive deformations owing to compression on the tubular component T. In particular, preferably, the extent of the deformations allowed by the core will only be in the resilient range, therefore without generating permanent deformations in the structure of the component T.
According to a preferred embodiment, the articulated core 3 comprises a rigid shaft, with which there are associated a plurality of rings 30 which are articulated to each other, as may be seen in Figures 7 and 8.
The articulation between the rings 30 may be constructed according to any known method, for example, by means of a plurality of spherical joints, not illustrated in the Figures.
In any case, as will become clearer below, the articulated core 3 is constructed so as to be able to bend during use at least about the bending axis Z.
Again with reference to Figure 3, the articulated core 3 is supported by way of rectilinear guide means 4 which allow the movement thereof in an axial direction X so as to be able to insert/withdraw it into/from the tubular component T.
Preferably, the guide means 4 comprise a pair of guides 41, on which there can slide a frame 42 which supports a rod 43 which is suitable for supporting in a removable manner the articulated core 3, so as to be able to replace it in accordance with the dimensions of the tubular component T which it is desirable to bend.
The movement of the frame is produced by means of an actuator 44 which is fixedly joined to the base 101. Preferably, the actuator is arranged in such a manner that the withdrawal of the rod therefrom corresponds to a movement of the articulated core 3 away from the tubular component T.
According to a preferred embodiment, the apparatus 100 further comprises a bending device 6 for producing the bent end T' of the tubular component T.
With reference to Figure 4, according to a preferred embodiment, the bending device 6 is fixed to the movable portion 102 and comprises an abutment cylinder 60 or other similar member which acts on the end of the tubular component T which is retained by the second retaining means 2. Preferably, the abutment cylinder 60 is further retained by means of a reinforcement rod 65 which extends between the cylinder and the pin coaxial with the axis Z.
More specifically, the tubular component T is arranged so as to be retained by the second retaining means 2 with a portion projecting with respect to the abutment edge 20. By moving the abutment cylinder 60 towards that projecting portion by means of a relevant actuator 61, illustrated in Figure 2, that portion of the tubular component is urged and deformed so as to bring about the bending of the end. There is thereby obtained a bent end which is suitable for being engaged with the abutment edge 20. Preferably, in the region of the bent end, the wall of the tubular component T is bent through approximately 90° with respect to the portion which is not bent.
Preferably, in this operating step, the articulated core 3 is advantageously inserted inside the component T, in order to ensure that the deformation takes place towards the outer side, thus obtaining the bent end T' desired. To that end, according to a preferred embodiment, the abutment cylinder 60 is produced by means of a tubular element inside which it is possible to insert an end of the articulated core 3. In particular, the articulated core 3 may be arranged so as to extend beyond the bent end T' of the tubular component T, in other words therefore being in an axial position which is more advanced with respect to that end, thereby providing a support which is suitable during the bending step.
Furthermore, in order to prevent movements of the tubular component T in the retraction direction during the production of the bent end, following the action of the abutment cylinder 60, an opposite end of the tubular component T abuts a block 45 which is fixedly joined to the rod 43 which supports the articulated core 3.
Preferably, during the operation of bending the end T', the block 45 is in abutment with an end wall 114 of the first retaining means 1.
Once the bent end T' is obtained, the tubular component T can be retained by the second retaining means so as to rotate that end about the bending axis Z. Preferably, the abutment cylinder 60 also acts on the bent end T' during the rotation thereof so as to retain the tubular component T in both the directions parallel with the axis X.
Since the opposite end is secured by means of the first retaining means 1 in directions normal with respect to the axis X, that rotation movement will involve the bending of the tubular component T.
During the advance of the end T', the articulated core is retained inside the tubular component.
However, the apparatus 100 comprises control means 7 which are illustrated schematically in Figure 1 and which are provided to control and coordinate the movement of the articulated core 3 with the rotation of the rotary portion 102.
More specifically, the control means 7 allow at least partial withdrawal of the articulated core 3 following a partial rotation of the rotary portion 102.
In greater detail, the bending method carried out by means of the apparatus 100 and the relevant control means 7 is constituted by a first step comprising bending of an end of the tubular component T so as to bring about the bent end T'.
That bending can be carried out according to the methods described above, that is to say, by retaining the tubular component T so as to define a portion thereof which projects with respect to the abutment edge 20, inserting the articulated core 3 therein and abutting the portion of the component T which projects from the edge 20 by means of an abutment cylinder, or it can be brought about in a preliminary manner according to other known methods.
The bent end T' obtained in this manner is therefore retained, preferably by means of the abutment edge 20 of the second abutment means 2, so as to prevent axial movements of the tubular component T in at least one direction.
However, the opposite end of the tubular component T is retained so as to prevent at least movements thereof which are normal with respect to the axial direction X of the tubular component T.
Subsequently, the articulated core 3 is inserted inside the tubular component T, preferably at least as far as the bent end T'.
The rotation of the bent end T' about the bending axis Z takes place in a gradual manner, preferably by subdividing a total bending angle α of the tubular component T into fractions of an angle.
In other words, the bent end T' is caused to rotate under operating conditions described above through a predetermined angle αi corresponding to a fraction of the total bending angle α. It is further evident that the rotation takes place in an opposite direction with respect to the axial direction in which the movements of the bent end T' are prevented. That rotation therefore involves the bending of the tubular component about the axis Z, for the reasons set out above. It may further be noted that the rotation of the bent end T' may be accompanied by an advance movement of the first retaining means 1, in accordance with what has been set out above.
The rotation is then stopped and, by retaining the bent end in the angular position reached, the articulated core 3 is removed at least partially from the tubular component T.
In this manner, the action of the articulated core 3 on the walls of the tubular component T allows any irregularities to be eliminated, allowing optimum surface finishing to be obtained. At the same time, the presence of the articulated core inside the tubular component T during the bending allows support to be provided therefor, thereby preventing compression and other deformations which are undesirable.
The steps of insertion of the articulated core 3, rotation of the bent end T' through a fraction of the total angle α and removal of the articulated core 3 are therefore repeated until a complete rotation of the bent end T' is obtained equal to the total bending angle α desired.
Now with reference to Figures 12 to 15, according to an alternative embodiment, the bending device 6 comprises a press 62 which actuates the abutment cylinder 60.
As may be observed in Figure 15, the press 62 comprises a support member 620 which is supported by means of a pair of guides 621 and 622 on the movable portion 102.
Preferably, the guide 621 which is parallel with the actuation direction of the press 62 is partially flexible so as to be able to compensate for any movements which take place during the rotation of the portion 102 in the bending steps of the tubular component T.
According to a preferred embodiment, the support member 620 further comprises two columns 64, on which there slides a sliding member 63 which supports the abutment cylinder 60 and which is actuated by means of an actuator which is also fixed to the support member 620.
Advantageously, the abutment cylinder 60 is fixed in an adjustable manner to the sliding member 63 so as to be able to adjust the position thereof within a plane perpendicular to the axis X of the tubular element T, in order to also allow centring for different diameters.
The presence of the press 62 allows the loads which are produced during the step of construction of the bent end T' to be withstood more effectively, and allows an improvement in the blocking thereof during the steps of bending of the component T about the axis Z.
The present embodiment further comprises a blocking device 7 of the tubular component T which comprises a fork-like element 70 which is mounted in a sliding manner on a column 71.
In greater detail, the fork-like element 70 can slide along an axis Y parallel with the axis Z so as to be able to be lowered on the tubular component T, in the region of a portion adjacent to the bent end T', partially surrounding the component T.
To that end, the fork-like element 70 has a curved edge 71 which has a shape complementary to the outer surface of the tubular component T so as to be able to retain it effectively, both in a direction parallel with the axis X and in directions perpendicular thereto.
The invention thereby solves the problem set out, achieving at the same time a plurality of advantages. In particular, the tubular component is not subjected to particular undesirable deformations during the bending, as a result of the use of the articulated core and the relative movement. The bending of the tubular component T is further carried out without the need for high levels of material waste, it being possible to retain the component only by means of the bent end which allows effective retention using only a minimal portion of the component.
The advantages set out above therefore make the apparatus according to the present invention particularly suitable for being used for tubes having great dimensions, while allowing small radii of curvature even in the case of small thicknesses of the wall of the tubular component.
In addition, the possibility of integrating the bending device in the apparatus according to the present invention allows the production of an integrated unit with a consequent advantage from the point of view of productivity.

Claims

An apparatus (100) for bending tubular components (T) comprising a support base (101), first and second retaining means (1, 2) of the tubular component (T) capable of retaining the tubular component (T) with respect to movements in a direction normal to an axis of longitudinal development (X) of the tubular component (T), the first retaining means (1) being supported on the base (101), and further comprising a rotary support portion (102) connected to the base (101) in a rotary manner about a bending axis (Z), the second retaining means (2) being supported on the rotary support portion (102), characterized in that it comprises an articulated core (3) which may be inserted inside the tubular component (T), may be bent at least about the bending axis (Z) and may move with respect to the base along rectilinear guide means (4) in a controlled manner coordinated with the movement of rotation of the rotary support portion (102), and in that the second retaining means (2) comprise an abutment edge (20) capable of abutting against a bent end (T') of the tubular component (T) so as to prevent axial movements of the tubular component (T) extracting it from the second retaining means (2).
An apparatus (100) for bending tubular components (T) according to claim 1, wherein the abutment edge (20) defines an opening which has dimensions which are sufficient to allow the passage of the tubular component (T) at a portion thereof which is not subjected to bending, but insufficient to allow the passage of the bent end (T').
An apparatus (100) for bending tubular components (T) according to claim 1 or claim 2, wherein the bent end (T') extends radially towards the outer side of the tubular component T.
An apparatus (100) for bending tubular components (T) according to any one of the preceding claims, further comprising a bending device (6) for bending an end of the tubular component (T) comprising an abutment member (60) which may be moved in order to abut against an end of the tubular component (T) projecting from the abutment edge (20).
An apparatus (100) for bending tubular components (T) according to any one of the preceding claims, wherein the first retaining means (1) and/or the second retaining means (2) comprise jaws (11, 12, 21, 22) on which there are defined respective opposing surfaces defining cylindrical surface portions shaped in a complementary manner with respect to the tubular component (T) and which may be moved towards/away from one another so as to retain the tubular component (T).
An apparatus (100) for bending tubular components (T) according to claim 5, wherein the second retaining means (2) comprise a jaw (21) which comprises a portion (211) extending in a rectilinear manner and a portion (212) extending in a curved manner, the portion (212) extending in a curved manner extending about the bending axis (Z) and being interposed between the bending axis (Z) and the tubular component (T) when the rotary portion (102) is rotated.
An apparatus (100) for bending tubular components (T) according to claim 5 or 6, wherein the first retaining means (1) comprise a jaw (12) which can move in a direction parallel with the longitudinal axis of a longitudinal component portion (T) of the first retaining means (1).
An apparatus (100) for bending tubular components (T) according to any one of claims 5 to 7, further comprising a toggle mechanism (13) for moving the jaws together/apart.
A method for bending tubular components (T) comprising:
- bending an end of the tubular component (T) so as to form a bent end (T');

- retaining the bent end (T') so as to prevent axial movements of the tubular component (T) in at least one direction;

- retaining an opposite end of the tubular component (T) in order to prevent, at the opposite end, at least movements normal with respect to a direction of axial development (X) of the tubular component;

- inserting an articulated core (4) inside the tubular component (T);

- rotating the bend end (T') about a bending axis (Z) through a predetermined angle (αi) corresponding to a fraction of an overall bending angle (α) of the tubular component, the rotation taking place in an opposite direction with respect to the axial direction in which the movements of the bent end (T') are prevented;

- extracting the articulated core (3) at least partially from the tubular component (T);

- repeating the steps of inserting the articulated core (3), rotating the bent end (T') through a predetermined angle (αi) and extracting the articulated core (3) until there has been obtained an overall rotation of the bent end (T') equal to the overall bending angle (α) of the tubular component (T).
A method for bending tubular components (T) according to claim 9, wherein the step of bending an end of the tubular component (T) is carried out by retaining the tubular component (T) with a portion projecting with respect to an abutment edge (20) and locally deforming the projecting portion by applying a stress by means of an abutment member (60).
A method for bending tubular components (T) according to claim 10, wherein the articulated core (3) is inserted inside the tubular component (T) during the step of bending an end.
A method for bending tubular components (T) according to any one of claims 9 to 11, wherein the articulated core (3) is partially inserted in/extracted from the tubular component (T) in a repeated manner, following the rotation through the predetermined angle (αi).