CZ19772U1 - Device for measuring wall thickness of large dimension objects - Google Patents

Description

Device for measuring the wall thickness of large bodies

Technical field

The invention relates to a device for measuring and determining the wall thickness of large-dimensional bodies, for example sheet metal containers or piping systems, in particular pipelines.

BACKGROUND OF THE INVENTION

Up to now, the wall thickness measurement of thin-walled large-dimension parts has been mainly carried out by mechanical gauges of various design solutions or by means of ultrasonic thickness gauges. In the case of the use of enclosed mechanical gauges, the possibility of measurement is limited by the dimensions of the measured components. When measuring large-dimensional bodies using ultrasonic thickness gauges, its reliability and reliability are only bound to a relatively flat surface. Therefore, this measurement is not suitable for measuring the thickness of a rugged surface that normally occurs on the surface of parts affected by point corrosion. Ultrasonic thickness gauges have not been proven even when measuring thickness at the surface of the cast part. In the case of measuring the thickness of piping systems, it is necessary to expose the measured points, which increases the time and cost of the performed measurement.

For these reasons, the use of existing measurement methods is limited because, for example, measuring irregular and rugged surfaces is not only very laborious and costly, but its results do not include displaying the real state of the measured parts in solid sections.

The essence of the technical solution

These drawbacks are overcome by a device for measuring the wall thickness of large-dimensional bodies, in particular sheet metal containers or piping systems according to the present invention. Its essence is that it consists of an iridium gamma-ray radiator for the measurement of the measured object, which is connected to a digital computer unit, which is connected to a block of graphical representation of contour lines to determine the topography of the surface of the measured large object. The iridium gamazarium is preferably portable.

The device according to the present technical solution enables not only operative measurement of selected areas of large-dimensional bodies, but also tabular or graphical evaluation of its results. This device is suitable for measuring sheet metal, vessel walls or tubes, etc., and the tubes can be tested including their insulation. The data obtained are directly applicable for the calculation of stresses in the material, for example by the finite element method. The dimensions of the measured objects are not limited and measurements can be carried out using both portable irradiated gamma-ray emitter and non-portable X-ray emitters. The measuring device and system can be advantageously applied especially in the determination of the residual lifetime of pipelines at risk of corrosion. In these measurements and subsequent evaluation it is possible to determine the corrosion loss of the pipe wall and the extent of its damage without removing the insulation. Reliability determination of safety, resp. the residual service life of the corrosion product pipelines is dependent on the accuracy of the description of the damaged pipe wall topography.

Examples of technical solution

The device according to the present invention was designed to determine the residual lifetime of pipelines while simultaneously detecting the extent of surface or spot corrosion of the pipeline surface.

The device consists of a portable irradiated gamma-ray radiator for the examination of a measured body by radiation, which is connected to a digital computer designed for processing measured values, which is connected to a block of graphical representation of contour lines to determine the surface topography of the measured large body. The measurement was performed on a 900 mm diameter pipe and a 12 mm pipe wall design thickness on a selected 2 m pipe section. This selected pipe section, irradiated with a portable irradiator, including its insulation, was shown

-1 CZ 19772 Ut on radiograms. Subsequent mathematical computer processing of the obtained radiograms of the measurement allowed to eliminate the effects of tube geometry on film blackening. A graphical representation of the topography of the surface defect of the measured pipe section using contour lines describing the topography of the surface defect of the measured pipe was achieved by computer tabular processing of the digital image poškozeníοί of this damage, using coordinates that were exposed during radiation. Then the wall thicknesses of the tube were determined by computer processing at the node points of the grids of any distance, as well as the minimum and maximum thicknesses together with their coordinates.

The graphical output was the contour lines of the measured area, when using the mathematical method for focusing the image, the software used allowed reliable determination of thicknesses despite the insulation. The detailed description of the topography of surfaces included not only the results of the measured value of the tube thickness in the selected irradiated area, but also the shape of its damage.

Industrial applicability

The device for measuring the wall thickness of large-dimensional bodies is widely used, both in testing rooms and in outdoor operating conditions.

Claims (2)

15 PROTECTION REQUIREMENTS A device for measuring the wall thickness of large-dimensional bodies, in particular sheet metal containers or pipe systems, characterized in that it consists of an iridium gamma-ray emitter for examining the measured body by radiation, the gamma-ray emitter being connected to a digital computer unit connected to a contour graphical block for determination of topography 20 of the surface of the measured large body. The device for measuring the wall thickness of large-sized bodies according to claim 1, characterized in that the iridium gamma emitter is portable.