Patent Application
20140190262
The invention relates to a feeding device for an ultrasound inspection system.
Guiding devices for guiding test objects in ultrasound inspection systems are known from the prior art. For example, DE 19931350 B4 discloses an inspection device for the ultrasound inspection of bar stock in which guiding means are provided on both end faces of the tubular container. The guiding means are thus configured for guiding the bar to be inspected in such a way that the bar to be inspected is disposed substantially concentrically with the cylinder axis. The guiding means can be assembled from two semi-annular portions.
Furthermore, a device for the non-destructive inspection of elongated test pieces with ultrasonic pulses is known from the utility model DE 7933989 U1, wherein a mutual guidance of the test piece and the test chamber is accomplished by means of guiding bushes.
The aforementioned documents are disadvantageous in that the guiding bushes must be replaced if the transverse dimension of the test objects changes.
Since faulty results occur during ultrasound inspection if the test objects are not fed into the ultrasound inspection chamber of the ultrasound inspection system in a centered manner, it is the object of the present invention to provide a simple and reliable feeding device. Moreover, it is an object of the present invention to enable a reliable ultrasound inspection of test objects with a changing cross section.
This object is accomplished by means of a feeding device with the features of claim 1, an ultrasound inspection system according to claim 11, and a method for ultrasound inspection according to claim 14. Advantageous embodiments are in each case the subject matter of the dependent claims. It must be remarked that the features cited individually in the patent claims can be combined in any technologically meaningful manner and depict other embodiments of the invention. The description, in particular in connection with the figures, additionally characterizes and specifies the invention.
The invention relates to a feeding device for an ultrasound inspection system with means for transporting a test object, in particular a pipe, into an ultrasound inspection chamber of the ultrasound inspection system. The feeding device according to the invention comprises at least one guiding unit with at least one, preferably three, still more preferably six elastically biased counter bearings. The counter bearings, via contact parts, rest on the jacket surface of the test object and guide the test object during transport.
The feeding device according to the invention is advantageous in that the test object is thereby fed into the ultrasound inspection chamber in a centered manner and that the ultrasound inspection can thus supply reliable results.
According to the invention, the counter bearings can be uniformly disposed in the circumferential direction of the jacket surface of the test object. In order to achieve an optimum distribution of the weight of the test object on the counter bearings, it is, however, also conceivable that the counter bearings are non-symmetrically disposed in the circumferential direction of the jacket surface; in this case, it is advantageous in particular if the majority of the counter bearings used are disposed under the test object.
In an advantageous embodiment of the invention, a spring, preferably a leaf spring and/or a rubber buffer, is provided as the means for elastically biasing the counter bearing in the direction of the test object. Preferably, this means can be individually biased, for example by a threaded adjustment option. It is thus possible to bias the counter bearings in a non-symmetrical way, for example, to bias those that rest against the lower side of the jacket surface of the test object more strongly than those counter bearings resting against the upper half of the jacket surface.
For the present invention, springs of spring steel are preferably used, such as e.g. the spring steel 38Si7. However, using other materials with an even higher elastic limit is also conceivable.
In an advantageous embodiment of the present invention, the counter bearings moreover have damping means. Damping means dampen the return movement of the counter bearing. The damping property is, for example, a property inherent in the rubber material used.
A rubber buffer which has a cross section that changes in the direction of the load is preferably used as an elastic returning means. The rubber buffer can be designed to have a conical, preferably parabolic, shape.
Natural rubbers are particularly suitable as materials for the rubber buffer. In a preferred embodiment, the rubber buffer has a Shore hardness of about 55. However, the use of any other material that exhibits an elastically dampening behavior is also conceivable.
In order not to damage the surface of the test object while it is guided through the ultrasound inspection system, the contact part preferably has to be designed in such a way that there is as little surface pressure as possible. This can be achieved, among other things, by as large a contact surface as possible between the contact part and the test object. In a preferred embodiment, the contact part is formed from a harder material than the test object; materials with a Rockwell hardness of at least 60 HRC, preferably at least 64 HRC, are particularly suitable for this purpose. However, it is also conceivable that a contact part of plastic is used.
According to a preferred embodiment, the contact part comprises a run-up surface. A run-up surface means a surface of the contact part which is inclined towards the direction of transport, in order to cause the contact part to pivot against the bias at least when the test object is inserted.
In an advantageous embodiment of the invention, the contact parts can be double-wedge bodies, preferably non-symmetrical double-wedge bodies. By using double-wedge bodies as contact parts, two run-up surfaces are defined and there is the option of feeding or transporting the test object not only in one direction, but in both directions. This is particularly advantageous if the test object has to be moved back and forth, for example if an area of the test object has to be re-inspected with ultrasound. The test object does not have to be guided out of the ultrasound inspection system completely and transported to the inlet of the ultrasound inspection system anymore. The test object can simply be moved back to the area to be inspected.
The method according to the invention is particularly suitable for the ultrasound inspection of rods and pipes. Preferably, pipes with a cross section that changes in the longitudinal direction, in this case particularly pipes with a thickened end, particularly preferably upset end pipes, are examined with the method according to the invention. Because of the elastic properties, the counter bearing or counter bearings adapt optimally to the different diameters of the test objects and position the test objects centrally in the ultrasound inspection system. However, it is also conceivable to examine other axially-symmetrical test object, such as, for example, a hexagon or nonagon with the ultrasound inspection method.
In the present invention, the test objects cause the counter bearings to pivot. Therefore, no external drives, such as motors, are required that increase the susceptibility to failure of the ultrasound inspection system.
Test objects with various diameters or cross sections can be examined with the ultrasound inspection system according to the invention. The pipes to be examined can have a diameter of a few centimeters, preferably smaller than 50 mm, particularly smaller than 80 mm.
An ultrasound inspection system in which the feeding device according to the invention is located outside the ultrasound inspection chamber must be considered particularly advantageous. On the one hand, this construction enables an easier access to the individual elements of the ultrasound inspection system. On the other hand, the ultrasound inspection chamber is used exclusively for ultrasound inspection, so that the inspection yields more reliable results.
The invention as well as the technical environment is explained in more detail below with reference to the figures. It must be remarked that the Figures depict a particularly preferred embodiment of the invention, but that they are not limited thereto. In the figures:
The figures show schematic views of a preferred embodiment of the present invention. The feeding device for an ultrasound inspection system comprises at least one guiding unit (1), preferably with elastically biased counter bearings (2) resting against a jacket surface (8) of the test object (7) via a contact part (4). The contact parts (4) can be configured as double wedges (4) in a preferred embodiment. In
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2010 031 637.7 | Jul 2010 | DE | national |
| 10 2010 038 973.0 | Aug 2010 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2011/062030 | 7/14/2011 | WO | 00 | 3/14/2013 |
