EP2406021B1 - Pipe bending machine with pipe manipulator - Google Patents

Description

The invention relates to a pipe bending machine and a method for loading and inserting pipes in pipe bending machines, with the features of the preamble of claim 1, such as from the DE 26 30 967 A known.

In such pipe bending machines, the pipes to be bent are inductively heated at the bending point. The pipes are often thick-walled steel pipes with wall thicknesses from 3 to 120 mm and with large diameters from 400 to 1660 mm and weights of several tons. The tube bending machines developed for this purpose are correspondingly large and heavy, with which bending radii of 1 to 10 meters can be realized.

The handling of the bent pipes is problematic. For each bend, the pipe to be bent must be clamped at its straight end in a feed carriage, while a bending lock is attached to the end to be bent. An annular device for inductive heating, usually also referred to as an induction ring, is located between the flexible lock and the feed carriage. This induction ring has to be dismantled in a complex manner during all reclamping and loading processes and then reinstalled and aligned, because otherwise there would be the danger that vibrating pipes would cause damage during transport. As a rule, this means a considerable delay in the bending processes, which significantly limits the turnover of a pipe bending machine. To solve such difficulties, other clamping devices for guiding pipes have also been described in the prior art.

The DE 26 30 967 A teaches to bend a pipe and to remove it from the bending device by means of a mandrel without having to remove the induction ring. However, the mandrel is not used as a feed and also not as a tool for gripping the pipe and inserting it into the pipe bending machine.

The DE 31 47 688 A1 describes a pipe quick-action clamping device with which the smallest possible, non-bendable pipe length is to be achieved at the clamping end, whereby a radial clamping movement is achieved by means of a bolt-shaped expanding collet with several longitudinal slots distributed around the circumference. For this purpose, the expanding pliers are also placed over one end of the pipe to be bent. With such a technology, however, only small differences in wall thickness can be compensated for and the tool cannot be used over a large range of pipe diameters. It is also not possible to pass the rear pipe end through the heating device.

In the FR 1 442 832 A it is intended to grip a thin-walled installation pipe from the inside and to feed it to a mechanical bending device. The device is not suitable for large and thick-walled pipes that can only be formed using the induction bending process.

More collets for pipes are in the scriptures DE 1 966 496 U. and US 2862540 described. However, these are also not suitable for picking up large pipes of different diameters and inductively bending them in pipe bending machines.

The object of the invention is therefore to provide a pipe bending machine in which the reclamping and loading processes are shortened and simplified and thus the throughput that can be achieved and the cost-effectiveness thereof are increased.

The object is achieved by a tube bending machine with the features of claim 1.

• In der Rohrbiegemaschine wird ein Rohr in axialer Richtung durch eine dieses Rohr ringförmig umschließende, Erwärmungseinrichtung geführt.
• Bei dem in Vorschubrichtung des Rohres gelegenen Teil der Rohrbiegemaschine befindet sich mindestens ein Biegearm,
• Ein am Biegearm befindliches Biegeschloss umfasst das zu biegende Rohrstück fest und bewegt sich während des Vorschubes des Rohres um die Biegedrehachse.
• Am Ende des Rohres ist eine axial in Vorschubrichtung des Rohres in der Vorschubeinrichtung verschiebbare Aufnahmepinole eingebaut.
• Die Aufnahmepinole greift von innen in das Rohr greift und spannt das Rohr dabei von innen fest.
• Die Aufnahmepinole führt das Rohr in definierter Weise axial durch die Erwärmungseinrichtung bis in eine vordere Spanneinrichtung.

Such a pipe bending machine is used to bend large diameter pipes and has a pipe manipulator for moving the pipes.

• In the pipe bending machine, a pipe is guided in the axial direction through a heating device which surrounds this pipe in a ring.
• There is at least one bending arm in the part of the pipe bending machine located in the direction of advance of the pipe,
• A bending lock located on the bending arm firmly encompasses the pipe piece to be bent and moves around the bending axis during the advance of the pipe.
• At the end of the tube, an accommodating quill that is axially displaceable in the feed direction of the tube is installed in the feed device.
• The pick-up gun reaches into the tube from the inside and clamps the tube from the inside.
• The pickup sleeve guides the tube axially in a defined manner through the heating device into a front clamping device.

This makes it possible to dispense with removing and reinstalling the induction ring, since the tube can be guided precisely through the induction ring until the rear tube end can be stretched far enough in front of the induction system without fear of evasive movements of the tube with a destructive effect are. The pickup gun applies the force with which the pipe is guided through the heating device. The pipe manipulator essentially consists of the receiving pin and the devices that serve to move the receiving pin in the axial direction, the latter corresponding to the usual feed devices according to the conventional art.

According to the invention, it is provided that the receiving pin fixes the pipe to be bent in at least two holding planes that are perpendicular to the horizontal pipe center axis. With such a tube inside Recording device, it is possible to hold the pipe so that it can not slip in the longitudinal direction or in the tangential direction. The two holding levels must be so far apart that they can safely absorb the large leverage forces without causing deformations at the force application points of the pipes. Additional holding levels can be provided as support.

It is also provided according to the invention that the fixation takes place in a frictionally locking manner in each of the holding planes by holding devices which are pressed against the tube from the inside. Due to the considerable forces, attention must be paid to defined, limited compressive forces and sufficient force application areas.

Furthermore, it is provided according to the invention that the receiving quill is rotatable. This facilitates clamping in the case of multiple bends and enables the tube to be rotated after several, possibly spatially complicated, bending processes in such a way that the tube can be removed safely.

In a further embodiment of the invention, it is provided that the holding devices are formed in each plane by holding levers which have force introduction elements for the inside of the tube at their outer ends, the holding levers being actuated by a hydraulic system within the receiving quill and being concentrically spread in the process. The holding levers can be arranged in the same direction or in opposite directions. In the event of a synchronism, the force introduction surfaces of the different holding planes can also be connected to one another.

In a further embodiment of the invention it is provided that three, four, five or six holding levers are provided in each of the holding planes, the holding levers being distributed uniformly over the circumference.

1. a) Positionieren des zu biegenden Rohres axial fluchtend vor dem Rohrmanipulator,
2. b) Einführen der Aufnahmepinole des Rohrmanipulators mit eingezogenen Haltehebeln in das Rohr, bis mindestens zwei Halteebenen innerhalb des zu biegenden Rohres sind,
3. c) Hydraulisches Ausfahren der Haltehebel, bis das Rohr durch die Aufnahmepinole festgehalten wird,
4. d) Heranziehen des Rohres durch die ringförmige Erwärmungseinrichtung (3) hindurch bis die Position, an der das Rohr in einem Vorschubwagen gespannt werden kann,
5. e) Schieben und gleichzeitiges Biegen des Rohres mittels induktiver Erwärmung,
6. f) Nach Beenden des Biegevorgangs Herausschieben des gebogenen Rohres durch die abgeschaltete Erwärmungseinrichtung (3) hindurch bis in das Biegeschloss (1),
7. g) Spannen des Rohres im Biegearmschloss,
8. h) Hydraulisches Einfahren der Haltehebel,
9. i) Herausführen der Aufnahmepinole aus dem Rohr,
10. j) Abtransport des Rohres.

A method for loading and guiding a pipe before and after a bending process using a pipe bending machine according to the invention comprises the following steps:

1. a) positioning the pipe to be bent axially aligned in front of the pipe manipulator,
2. b) inserting the receiving manipulator of the pipe manipulator with retracted holding levers into the pipe until at least two holding levels are inside the pipe to be bent,
3. c) Hydraulic extension of the holding levers until the pipe is held by the pick-up gun
4. d) pulling the tube through the ring-shaped heating device (3) until the position at which the tube can be tensioned in a feed carriage,
5. e) pushing and simultaneously bending the tube by means of inductive heating,
6. f) after the bending process has ended, the bent tube is pushed out through the switched-off heating device (3) into the bending lock (1),
7. g) tensioning the tube in the bending arm lock,
8. h) hydraulic retraction of the holding lever,
9. i) leading the pick-up gun out of the tube,
10. j) removal of the pipe.

It is therefore no longer necessary to position the tube with cranes in the bending machine. Furthermore, conventional bending operations can be carried out in one, without waiting for the pipe to cool, which reduces productivity significantly improved because it speeds up the entire bending process considerably. The removal can then be carried out in a simple manner, for example by means of an indoor crane.

During the bending process, care must be taken to ensure that no holding levers are extended when the force application surface in question comes close to the induction ring, but that the holding levers are in a parking position.

Fig. 1

zeigt hierbei eine Übersicht über die Teile der Biegemaschine und ihr Zusammenwirken mit dem Rohrmanipulator.

Fig. 2a bis 2d

zeigen eine Aufnahmepinole mit eingefahrenen, und

Fig. 3a bis 3d

mit ausgefahrenen Haltehebeln.

The invention is explained in more detail below on the basis of nine sketches.

Fig. 1

shows an overview of the parts of the bending machine and their interaction with the pipe manipulator.

2a to 2d

show a shooting gun with retracted, and

3a to 3d

with extended holding levers.

Fig. 1 shows the bending machine with a bending lock 1, the bending axis of rotation 2, behind which there is also an induction ring 3 in the same plane. On the front part of a feed carriage 4 there is a pickup 5 which is connected to a feed rod 6 and has the holding lever 7. Pickup gun 5, feed rod 6 and holding lever 7 form the pipe manipulator. The inserted tube 8 is shown up to the induction ring 3 and is then only shown in dashed lines in the unbent state.

Fig. 2a shows a side view of the pipe manipulator consisting of the pickup 5, feed rod 6, the four holding levers 7 in the retracted state and their force introduction surfaces 9.

Fig. 2b shows a 45 ° cut, Fig. 2c a frontal view in the axial direction and Fig. 2d an isometric representation.

Shows in the same way Fig. 3a a side view of the pipe manipulator consisting of the pickup 5, the feed rod 6, the four Retaining levers 7 in the extended state and their force introduction surfaces 9. The holding planes 10 are also shown here.

Fig. 3b shows a 45 ° cut, Fig. 3c a frontal view in the axial direction and Fig. 3d an isometric representation.

Reference list

1

Bending lock

2nd

Bending axis of rotation

3rd

Induction ring

4th

Feed carriage

5

Pickup quill

6

Feed rod

7

Holding lever

8th

pipe

9

Force application area

10th

Holding level

Claims (4)

1. A pipe bending machine for bending pipes (8) of large diameter, wherein

   - a pipe manipulator is provided for moving the pipes, by means of which a pipe (8) is guided in the axial direction through a heating means (3) which annularly surrounds the pipe (8),

   - at least one bending arm is located in the part of the device for bending which is situated in the feed direction of the pipe (8),

   - a bending lock (1) located on the bending arm firmly encompasses the pipe piece to be bent and moves about the bending axis of rotation (2) while the pipe is being advanced,

   characterised in that the pipe manipulator comprises a feed rod (6), a holding lever (7) and a receiving sleeve (5) which is rotatable, axially displaceable in the feed direction of the pipe (8) and which:

   - is installed at the end of the pipe (8) in the feed means (4),

   - is designed for engaging in the pipe (8) from the inside and for firmly clamping the pipe (8) from the inside, and

   - is displaceable for guiding the pipe (8) in a defined manner through the heating means (3) into the bending arm lock (1),

   and that the pipe (8) to be bent can be fixed by the receiving sleeve (5) in at least two holding planes (10) which are perpendicular to the pipe centre axis, and that the fixing takes place in a frictional manner in each of the holding planes (10) by the holding levers (7) which can be pushed against the pipe (8) from the inside.
2. The device according to claim 1, characterised in that the holding levers (7) have force introduction elements (9) at the outer ends thereof for the inner side of the pipe and are actuated by a hydraulic system within the receiving sleeve (5) and can be expanded concentrically.
3. The device according to claim 2, characterised in that three, four, five or six holding levers (7) are provided in each of the holding planes (10), said holding levers being distributed uniformly over the circumference.
4. A method for loading and guiding a pipe (8) before and after a bending process by means of a device according to claim 2 or 3, characterised by the following steps:

   a) positioning the pipe (8) to be bent in an axially aligned manner in front of the pipe manipulator,

   b) inserting the receiving sleeve (5) of the pipe manipulator with retracted holding levers (7) into the pipe (8) until at least two holding planes (10) are inside the pipe (8) to be bent,

   c) hydraulically extending the holding levers (7) until the pipe (8) is held in place by the receiving sleeve (5),

   d) pulling the pipe (8) through the annular heating means (3) into a position at which the pipe (8) can be tensioned in a feed carriage (4),

   e) pushing and simultaneously bending the pipe by means of inductive heating,

   f) pushing the bent pipe (8) out through the switched-off heating means (3) into the bending lock (1) after the bending process has ended,

   g) clamping the pipe (8) in the bending lock (1),

   h) hydraulically retracting the holding levers (7),

   i) guiding the receiving sleeve (5) out of the pipe (8), and

   j) removing the pipe (8).

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