WO2009019210A1

WO2009019210A1 - Tube coiling/decoiling machine and relative process

Info

Publication number: WO2009019210A1
Application number: PCT/EP2008/060122
Authority: WO
Inventors: Stefano Lodolo; Bruno Chiuch
Original assignee: Danieli & C. Officine Meccaniche S.P.A.
Priority date: 2007-08-03
Filing date: 2008-08-01
Publication date: 2009-02-12
Also published as: ITMI20071609A1; BRPI0814328A2; EP2188075A1; CN101795787A; EP2188075B1

Abstract

Tube coiling/decoiling machine, used in particular downstream of a rolling mill, capable of significantly increasing the production rate by automating numerous operations, consequently reducing labour costs. In particular said coiling/decoiling machine comprises a drum (7), suitable for rotating around its longitudinal axis, provided with a cavity (9) for containing the first end of the tube (13) corresponding to a peripheral portion there of. A relative tube coiling/decoiling process more efficient than the one currently used is described.

Description

Tube coiling/decoiling machine and relative process

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Field of the invention

The present invention refers to a metal tube coiling/decoiling machine, and the relative process, which can be used in particular downstream of the rolling plants. State of the art

Downstream of the rolling mill for tubes, made of copper for example, a coiling/decoiling machine is normally positioned which has the function of winding the straight tube coming from the rolling mill into a coil, supporting the coil formed and subsequently unwinding it for the drawing processes downstream.

As the length of a rolled tube is greater than 100 metres, the winding thereof into coils, weighing at least 500 kg, reduces its overall dimensions. The material of these tubes can be easily deformed as it has been annealed by the rolling process upstream. Said coiling/decoiling machine has a cross-shaped structure provided with two or four coil supporting stations, each being equipped with two motorised rollers provided with grooves, with axes positioned horizontally supporting the entire weight of the coil. Between the rolling mill and the coiling/decoiling machine the following are nor- mally present:

- a shearing unit which cuts the beginning and end of the tube, portions which have been deformed by the last rolling unit and which are therefore non- conforming;

- an independent bending unit, fixed to the ground, which bends the tube to form the coil.

After being cut by the shearing unit, the beginning of the tube passes through the bending unit at the coiling machine inlet and is bent to form the coil. Between the tip and the first wound turn of the tube, two or more supporting clamps are manually applied to prevent interference with the tip which would otherwise become de- tached at every turn of the coil. The winding continues until the rolling mill has completed the cycle and the end of the tube is cut as it has been deformed and is therefore non-conforming. The machine is then rotated 180° in the case of a machine with two stations, or 90° in the case of a machine with four stations, and the tube is cleaned inside by means of a jet of air directed manually.

The end of the tube becomes the beginning of the coil for the following processes. The beginning of the coil is prepared for the subsequent drawing operations with insertion of plug and oil inside the tube for drawing of the internal diameter and is squeezed, preferably tapered, in order to pass through the die plate and be gripped by the traction assemblies downstream, comprising tracks or cam-type pulling benches or other.

Once the coiling/decoiling machine has been rotated 90°, in the case of four stations, the tapered lead end of the coil is fed manually towards the traction assemblies downstream and the tube is gripped and drawn at speed right through to the last turns of the coil. At this point the drawing speed must be reduced to minimum, the supporting clamps manually removed and the end of the coil manually supported.

Disadvantageously when using the machine in the state of the art, numerous operations have to be performed manually during the coiling/decoiling process. This involves a slowdown in production and significant labour costs, in addition to in- creased operator risks to the detriment of safety.

The need is therefore felt to produce an automatic tube coiling/decoiling machine and relative process able to overcome the above-mentioned drawbacks. Summary of the invention The primary object of the present invention is to produce a tube coiling/decoiling machine, used in particular downstream of a rolling mill, which results in a significant increase in production rate by automating numerous operations, consequently reducing labour costs and improving operator safety. A further object of the present invention is to provide a relative tube coiling/decoiling process which is more efficient and quicker than the conventional method.

A further object of the invention is to produce a tube coiling/decoiling machine which allows the coil to be supported without damaging the surface and the shape. The present invention, therefore, aims to achieve the above-mentioned objects by producing a coiling/decoiling machine for at least one tube moving in a predetermined direction which, as claimed in claim 1 , comprises bending means to bend a first end of the tube and guide it so as to form a coil, a cross-shaped struc- ture in which each arm of said cross is provided with means for winding/unwinding said coil, said structure being suitable for rotating, thereby moving said coiling/decoiling means from a coiling station to a decoiling station, characterised in that said coiling/decoiling means comprise a drum, suitable for rotating around its longitudinal axis, provided with a cavity for containing said first end of the tube cor- responding to a peripheral portion thereof.

According to a further aspect of the invention, a process is provided for coiling/decoiling at least one tube moving in a pre-determined direction, via use of the above-mentioned coiling/decoiling machine which, as claimed in claim 1 1 , comprises the following phases: a) bending of the tube by means of said bending means at the inlet of a coiling station; b) insertion of a first end of the tube in a containing cavity provided in the drum of said coiling station, so as to automatically support said first end during rotation of the drum, and winding of the tube in a coil on said drum. Advantageously the coiling/decoiling machine, subject of the present invention, allows automation of the following operations:

- supporting and guiding the beginning and end of the coil by means of a drum provided with recess or containing cavity, also during movement of the coil from one station to another of the machine;

- restoration of the diameter and internal cleaning of the tube;

- tapering of the tube;

- feed-in of the tapered lead end of the coil towards the traction assemblies downstream. A further advantage of the device of the invention is represented by the fact that the machine has, on each arm of the cross-shaped structure, a drum with recess for containing the tube and provided with bending machine/curve aiding device and beginning and end of coil support, thus guaranteeing a high production rate for the entire tube production line.

The dependent claims describe preferred embodiments of the invention. Brief description of the figures Further characteristics and advantages of the invention will become clearer in the light of the detailed description of preferred but not exclusive embodiments of a tube coiling/decoiling machine illustrated, by way of non-limiting example, with the help of the accompanying drawings in which: Fig. 1 shows a plan view of the machine according to the invention; Fig. 2 shows side views of a component of the machine of Fig. 1 in the various stations of said machine;

Fig. 3 shows a side view of the coil winding and unwinding stations of the machine of Fig. 1. Detailed description of preferred embodiments of the invention With reference to the figures cited, a tube coiling/decoiling machine according to the invention, indicated overall by reference number 1 , generally provided between a rolling mill (not illustrated) and traction assemblies downstream for the subsequent work processes, comprises a cross-shaped structure 2 and is provided with a work station corresponding to each arm of the cross. These work stations comprise:

- a winding station 3 for forming a tube coil;

- a station 4 for tapering one end of the tube;

- a station 5 for unwinding the coil of tapered tube;

- a waiting station 6. On each arm of the cross-shaped structure 2 there is a coil supporting drum 7, to which a bending machine 8 is integrally fixed below.

The cross-shaped structure 2 is suitable for rotating 90° around its axis X to move the drum 7 and bending machine 8 from one station to the other each time during a coiling/decoiling cycle. Advantageously the drums 7 are provided with a recess 9 to contain the beginning or tip of the tube coming from the rolling mill and appropriately bent by the bending machine 8. This solution of using drums provided with containing recess per- mits elimination of the manual operation for application of the supporting clamps between the tip and the first coiled turn of the tube on the motorised rollers to prevent interference with the tip.

The recesses or cavities 9 of the drums 7 can be provided inside with means for locking and releasing the beginning of the tube coming from the rolling mill. Said locking and releasing means are such as not to deform this end of the tube contained in the recess 9. The bending machine 8 and drum 7 are motorised by means of respective inde- pendent controls 8', 8", T 7", engaged/disengaged by means of special joints and fixed on the ground both in the coiling station 3 and in the decoiling station 5, as illustrated in figures 1 and 3.

In the example of Fig. 3 the independent controls T, 7" transmit the rotation to the drums 7 around their axes in the stations 3 and 5 by means of a chain transmis- sion system 14 or other suitable system.

The bending machine 8 and drum 7 are provided with respective brakes, for example disc brakes, independent and mounted on board, so that they can be kept still in position during rotation of the cross-shaped structure and in the tapering station 4 and waiting station 6. Upstream of the coiling station 3 a shearing unit is provided (not illustrated) for cutting the beginning and end of the tube coming out of the rolling mill, as the material of these parts of the tube has been deformed during rolling. Alternatively, the rolled tube can come from a warehouse. The tapering station 4 is advantageously provided with an automatic tapering unit 10 mounted on a carriage 1 1 which permits movement thereof to the work position.

A further advantage is represented by the fact that on the front of the automatic tapering unit 10 a retractable automatic device 12 is fitted for restoring the internal diameter of the tube deformed by the shearing unit and for internal cleaning of the tube. The entire coiling/decoiling process of a tube 13, for example a copper tube, com- ing from a rolling plant or rolling mill, is described below.

The rolling mill processes the tube 13 having a length greater, for example, than 100 metres, in a straight form.

When it comes out of the rolling mill, the tip of the tube, after being cut by the shearing unit, passes through the bending machine 8 at the inlet to the coiling station 3 of the machine 1 and is bent to form the coil on the drum 7. Advantageously the tip of the tube is inserted by the bending machine 8, operated by the relative control 8', into the containing recess 9, provided in the drum 7, and is automatically supported during rotation of the drum around its axis controlled by the relative independent control T.

The coiling continues until the rolling mill has completed the cycle and the end of the tube is cut by the shearing unit.

Once coiling of the tube 13 on the drum 7 has been completed, the cross-shaped structure rotates 90°, moving the coil to the tapering station 4. The end of the tube 13 is supported during rotation of the bending unit 8 and now becomes the tip or beginning of the tube coil for the processes downstream.

During rotation of the cross-shaped structure and in this tapering station 4, the bending unit 8 and drum 7 are kept still in position by means of two independent disc brakes mounted on board. The retractable automatic device 12, on the front of the automatic tapering unit 10, is initially in line with the tube 13. The tapering unit 10 moves forward to the work position and positions itself in contact with the tube so that the device 12 can restore the diameter of the tube and clean it inside. Subsequently the tapering unit 10 withdraws to the waiting position, the device 12 shifts and the tapering unit moves forward again to the work position in order to automatically perform the following operations:

- insertion inside the tube of plug and oil for drawing of the internal diameter;

- tapering of the beginning of the tube coil.

Once the tapering operation has been completed, the tapering unit 10 withdraws again to the waiting position and the cross-shaped structure 2 rotates 90°, thereby moving the coil to the unwinding station 5. During rotation, the tip or beginning of the tube coil is supported by the bending unit 8. In this decoiling station 5, the bending unit 8 and drum 7 are operated again by the respective independent controls 8", 7" fixed on the ground and engaged/disengaged by means of special joints.

The bending unit and drum, rotated in the coil unwinding direction, automatically feed the tube to the traction assemblies 15 downstream, comprising tracks or cam-type pull benches or other. The tube 13 is then gripped and drawn at speed in a drawing machine 16 and the end of the coil is automatically supported by the recess 9 of the drum and by the bending unit 8. Once decoiling of the tube 13 has been completed, the cross-shaped structure 2 rotates again 90°, moving the drum 7 and the relative bending unit 8 to the waiting station 6. At this point the machine waits for the next 90° rotation to begin a new coiling/decoiling cycle.

In a variation (not illustrated) of the coiling/decoiling machine of the invention, the waiting station can be located between the coiling station and the tapering station. This configuration provides a tube coil unwinding direction perpendicular to the rolling direction.

In this case, once coiling of the tube 13 on the drum 7 has been completed, the process of the invention provides for the cross-shaped structure to rotate 90°, moving the coil to the waiting station. This is followed by three successive 90° ro- tations of the cross-shaped structure 2 to move the drum 7 and bending unit 8 to the tapering station, to the decoiling station and to the coiling station respectively to begin a new coiling/decoiling cycle.

Claims

1. Machine for coiling/decoiling at least one tube (13) in a pre-determined direction, comprising bending means (8) to bend a first end of the tube (13) and guide it so as to form a coil, a cross-shaped structure (2) wherein each arm of said cross is provided with means for winding/unwinding said coil, said structure being suitable for rotating, thereby moving said coiling/decoiling means from a coiling station (3) to a decoil- ing station (5), characterised in that said coiling/decoiling means comprise a drum (7), suitable for rotating around its longitudinal axis, provided with a cavity (9) for containing said first end of the tube corresponding to a peripheral portion thereof.

2. Machine as claimed in claim 1 , wherein one of said bending means (8), suitable for supporting a second end of the tube coiled on the drum (7) and for acting as an aid during unwinding of the coil, is fixed integrally to each drum (7).

3. Machine as claimed in claim 2, comprising a tapering station (4), in an intermediate position between the coiling (3) and decoiling (5) stations, provided with an automatic tapering unit (10) to taper the second end of the tube, positioned on a carriage (1 1 ) which permits movement thereof from a waiting position to a work position.

4. Machine as claimed in claim 3, wherein on the front of the automatic tapering unit (10) an automatic retractable device (12) is positioned suitable for restoring the diameter of the tube and cleaning the inside of the tube before the tapering operation.

5. Machine as claimed in any one of the preceding claims, wherein in said decoiling station (5) traction assemblies (15) are provided suitable for being automatically fed with the tube being decoiled by the corresponding drum (7) and bending unit (8).

6. Machine as claimed in any one of the preceding claims, wherein at the level of said coiling (3) and decoiling (5) stations, first controls (7', 7") and second controls (8', 8") are provided, independent from each other, for operating the drums (7) and bending units (8) respectively.

7. Machine as claimed in claim 6, wherein joints are provided for engaging and disengaging said first and second controls (7', 7", 8', 8").

8. Machine as claimed in claim 7, wherein the first controls (7', 7") are suitable for transmitting a rotation to the drums (7) around their axes by means of a chain transmission system (14).

9. Machine as claimed in any one of the claims from 6 to 8, wherein drums (7) and bending means (8) are provided with respective independent brakes.

10. Machine as claimed in any one of the preceding claims wherein a waiting station (6) is provided between the decoiling station (5) and the coiling station (3) or between the coiling station and the tapering station.

1 1. Process for coiling/decoiling at least one tube (13) moving in a pre-determined direction, by means of a coiling/decoiling machine comprising bending means (8) to bend a first end of the tube (13) and guide it so as to form a coil, and a cross- shaped structure (2) wherein each arm of said cross is provided with means for winding/unwinding said coil comprising a drum (7), said structure being suitable for rotating, thereby moving said drum from a coiling station (3) to a decoiling station (5), said process comprising the following stages: a) bending of the tube by means of said bending means (8) at the inlet to a coiling station (3); b) insertion of a first end of the tube in a containing cavity (9) provided in the drum (7) in said coiling station, so as to automatically support said first end during rotation of the drum, and coiling of the tube on said drum (7).

12. Process as claimed in claim 1 1 entailing, after stage b), a first rotation of the cross-shaped structure (2) to move said drum (7) and bending means (8) to an intermediate tapering station (4) between the coiling (3) and decoiling (5) stations, a second end of the tube being supported by said bending means (8) during said first rotation.

13. Process as claimed in claim 12, wherein said tapering station (4) provides for tapering of said second end of the tube (13) by means of an automatic tapering unit (10).

14. Process as claimed in claim 13, wherein before the tapering operation, plugs and oil are inserted inside the tube for drawing of the internal diameter by means of said automatic tapering unit (10).

15. Process as claimed in claim 14, wherein before the tapering operation, the tube diameter is restored and the tube is cleaned inside by means of an automatic retractable device (12).

16. Process as claimed in one of the claims from 13 to 15 entailing, after the tapering operation, a second rotation of the cross-shaped structure (2) to move said drum (7) and bending means (8) to the decoiling station (5), the second end of the tube being supported by said bending means (8) during said second rotation.

17. Process as claimed in claim 16, wherein in said decoiling station (5) the bending means (8) and the drum (7) are rotated in the coil unwinding direction in order to automatically feed the tube to the traction assemblies (15) downstream.

18. Process as claimed in claim 17, wherein during unwinding of the coil, the first end of the tube is automatically supported by the containing cavity (9) of the drum (7) and by the bending means (8).

19. Process as claimed in claim 18 entailing, after the decoiling operation, a third and a fourth rotation of the cross-shaped structure (2) to move said drum (7) and bending means (8) respectively to a waiting station (6) and then to the coiling station (3) to begin a new coiling/decoiling cycle.

20. Process as claimed in claim 18 entailing, before the first rotation of the cross- shaped structure (2), a third rotation of said structure (2) to move the drum (7) and bending means (8) to a waiting station (6) and entailing, after the decoiling operation, a fourth rotation of the cross-shaped structure (2) to move the drum (7) and bending means (8) to the coiling station to begin a new coiling/decoiling cycle.

21. Process as claimed in claim 19 or 20, wherein in said tapering station (4), in said waiting station (6) and during the rotations of the cross-shaped structure (2), the bending means (8) and drum (7) are kept still by means of respective independent brakes.