SK4452003A3 - Magnetic induction flaw detector for the external inspection of small diameter pipes, pressure tanks and for the internal inspection of large diameter pipes and pressure tanks - Google Patents

Abstract

The subject matter of the patent is a diagnostic device which enables non-destructive control of ferromagnetic materials. The device is primarily intended for diagnosis steel pipes, pressure vessels, sheets of various thicknesses. The task of the device is to indicate differently oriented fault points, cracks or cracks in the internal and the outer surface of the test body.

Description

. Magnetoinductive flaw detector for external inspection of small diameter pipes, pressure vessels and for internal inspection of large diameter pipes and pressure vessels.

Technique Area

The invention relates to technical diagnostics where it helps to extend the possibilities of detecting the real state of above-ground metallic pipelines of ferromagnetic materials.

BACKGROUND OF THE INVENTION

The steel wire rope test room is authorized by the authorization no. 119/2002 for the authorized person SKTC - 147 in accordance with the provision of Section 11 of Act No. 264/1999 Coll. for testing of specified products according to the Regulation of the Government of the Slovak Republic no. 400/1999 Coll. The Steel Rope Testing Room (SOL) is a testing laboratory accredited by SNAS bodies no. S 098/02 providing services in the field of testing steel ropes and chains used in mining, transport and textile ropes for life-saving equipment. SOL services are divided into accredited, non-accredited and other activities.

In addition to testing, SOL is also engaged in research and development of new diagnostic equipment for various industries. The attention of SOL workers is currently focused on the gas sector. All diagnostic devices used so far in this area are designed as single-purpose. The uniqueness of these devices is linked to the fact that they are designed solely for the diagnosis of pipelines. In addition, they are capable of indicating defects oriented in only one direction relative to the direction of movement of the machine. Their use is also limited by the dimensions of the pipeline under test.

SUMMARY OF THE INVENTION

The MAG-1.0 object of the invention is a unique diagnostic device. The device is completely different from the diagnostic tools used so far. New design solutions have been applied to this instrument, which has been made possible by the development of new materials. Compared to comparable devices, the dimensions and design changes have been reduced several times, resulting in a more versatile application and will make it possible to reliably detect defects even in unsuitable locations for diagnostics. The device consists of several basic parts and these are:

Rare earth magnet,

The yoke of the magnetic circuit,

Rotary magnetic circuit carrier,

Carrying case,

Stabilization equipment,

Measuring device,

Ancillary and supplementary parts,

The rare earth magnet is composed of a mixture of NdFeB and has been obtained by the supplier process. Compared to conventional magnets, it is characterized by high magnetic power while maintaining minimum dimensions.

The yoke of the magnetic circuit has the task of transferring the magnetic field of the rare earth magnet to the test material, which must be magnetically active. The transfer of magnetic energy, the magnetic field, is performed without contact. The yoke of the magnetic circuit consists of L-shaped components made of magnetically mild steel (with a remanent magnetic induction value close to zero and a low coercive force). The yoke of the magnetic circuit is made by milling.

The rotatable magnetic circuit carrier has the task of retaining the magnet and the yoke of the magnetic circuit so as to assume an optimal position relative to each other, i. to touch each other across the board. At the same time, a measuring coil is mounted on the rotary carrier, which is immovable in order to ensure that only the relevant signal is transmitted to the magnetic field transmitting parts. The swivel carrier is made of non-magnetic material.

Carrier housing, its task is to carry a rotatable magnetic field carrier. In addition, the carrier housing is provided with protrusions that allow the attachment of the stabilizing devices and a locking screw with a corresponding groove that rotates the rotating magnetic field carrier by 90 °. The advantage of the rotating solution is that the device can reliably indicate surface cracks and fissures at 0 ° rotation, at 90 ° perpendicular rotation and at 45 ° rotation both parallel and perpendicular to the direction of movement of the diagnostic device. The magnetic circuit carrier housing is made of a non-magnetic material.

The purpose of the stabilization devices is to keep the magnetic circuit support in an optimal position relative to the material under test. It consists of supporting and supporting wheels, and their carriers, provided with holes for fastening to the carrier housing. Wheel carriers are made of non-magnetic material. The support wheels used are in two dimensions, namely according to their location relative to the carrier housing. In the center are drilled holes in which there is a non-magnetic self-lubricating housing. Wheel axles pass through the wheel housing, by means of which the wheels are attached to the wheel carriers. The wheels are made of non-magnetic material.

The measuring device consists of a sensing element - coil system, analyzer with source, converter and computer. The task of the measuring device is to detect, monitor and record changes in the induced electrical voltage in the coil, which is caused by a change in the magnetic field strength in the test material. The intensity of the magnetic field in the magnetically conductive material usually changes if the magnetic circuit is disturbed due to the material's inconsistency. The signal output from the coil is transmitted to the portable computer through the analyzer with the source and converter, which records the measured signal to the hard disk by means of suitable software and at the same time visualizes it on the computer monitor. The coils are housed in a housing of non-magnetic material. The coil housing is provided with a groove that serves to adjust the optimum position of the coils to the material being monitored. The coils are made by winding copper wire onto a ferromagnetic core.

Auxiliary and additional parts of the diagnostic equipment include connecting screws, connecting cables.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1 is an overall view of a base portion of the apparatus.

Carrying case,

Carrier housing lugs,

Load wheel,

Locking screw,

Stabilizing device,

Locking screw action groove,

A-A Section plane

B - B Section plane.

In FIG. 2 is a cross-sectional view of the base portion of the apparatus of FIG. 1 along the plane B-B.

Rare earth magnet,

The yoke of the magnetic circuit,

Rotary magnetic circuit carrier,

Carrying case,

Carrier housing lugs,

Load wheel.

In FIG. 3 is a cross-sectional view of the base portion of the apparatus of FIG. 1 by plane A - A.

Rare earth magnet,

Rotary magnetic circuit carrier,

Carrying case,

Carrier housing protrusion,

Load wheels,

Locking screw,

Coil housing,

coils,

Coil diameter adjusting screw.

In FIG. 4 shows a stabilizing device.

Support wheel carrier,

Support wheel.

DETAILED DESCRIPTION OF THE INVENTION

At present, the diagnosis of pipelines, especially gas pipelines in our territory, is carried out by a foreign company, with almost all attention being paid to the pipelines of the international transit system that transports natural gas from its sites in the Russian Federation to consumers in Western Europe. The international transit pipelines are buried underground over their entire length, so that their condition is checked in the form of so-called "ground". internal inspection. This means that underground buried pipes are diagnosed reliably and regularly. In contrast, maintenance of pipelines stored above ground is insufficient. It is carried out only rarely and only in places where the greatest wear is expected, ie in places where the direction of the pipeline changes. To date, no reliable device has been developed for diagnosing defects in above-ground pipelines, particularly as regards straight sections. As SOL employees are also employees of the Department of Petroleum Engineering of the Faculty of Mining, Ecology, Management and Geotechnology of the Technical University of Košice, they are in constant contact with the employees of companies engaged in the extraction, treatment and distribution of hydrocarbons such as. SPP as, SPP DZ Slovtransgas Nitra, SPP DZ Slovtransgas Senica, Nafta a.s. Gbely, Nafta Záhorie, Nafta Východ and Naftagas Malacky. The maintenance experts of the aforementioned companies interpreted their requirements for the diagnosis of overhead pipelines. Equipment for performing such maintenance shall be universal, efficient, efficient and easy to operate. Therefore, SOL workers have increasingly engaged in the development of a new diagnostic device for diagnosing surface cracks and fissures in above-ground pipelines of different diameters.

The device can be used to test the surface of the steel pipes of pipelines by placing the device freely on the surface of the pipeline and the stabilizers ia JO with wheels 6 and 2 (Fig. 4) are placed in the optimum position so that the carrier sleeve 4 has taken the desired position relative to the pipe. By means of the locking screw 7, the desired direction of the material magnetization can be set in the range of 0 ° - 90 °. The yoke of the magnetic circuit 2, thanks to the rare earth magnet, also creates a magnetic circuit. The induced electrical voltage is induced in the coils by the movement of the magnetic field, the course of which is sensed and recorded. The coil diameter adjusting screw 12 can be used to adjust the distance between the coils and the surface of the test material, optimizing the sensed signal.

MAG - 1.0 works on the principle of magnetic stray fluxes. This method has exceptionally proven in practice. A reliable method for the determination of surface cracks, surface cracks and cold joints on magnetically conductive materials is considered worldwide.

Currently, the equipment is used by SOL personnel to determine the true surface condition of steel sheets and pressure vessels.

Diagnostic Device Design:

The entire diagnostic device is composed of several pieces as described in the Summary of the Invention. The exact number of these parts is determined by the particular field requirements i.e. pipe diameter. The individual parts are placed one after another and next to each other on a checkerboard principle so that the device is able to map 100% of the pipeline perimeter in one passage.

The individual segments are interconnected by screws so as to be movable relative to each other, which improves the throughput of the device on deformed pipe sections and welds.

The individual parts of the diagnostic equipment were made on the basis of technical documentation, written by Ing. Jozef Krešák PhD, and Ing. Pavel Peterka Production of the mechanical part was carried out in cooperation with the Development Workshops and Laboratories of the Faculty of Mechanical Engineering of the Technical University of Košice and the Department of Iron Metallurgy and Foundry of the Faculty of Metallurgy of the Technical University of Košice. The production of the electronic part including the coils was carried out solely under the direction of SOL Ing. Pavel Peterko PhD.

Claims (5)

Patent claims 1. MAG —— L & - - Magneto-inductive flaw detector for external inspection of small diameter pipes, pressure vessels and for internal inspection of large diameter pipes and pressure vessels - characterized in that it has a segment design and a rotatable yoke of magnetic circuit. 2. - Magnetoinductive flaw detector for external inspection of small diameter pipes, pressure vessels and internal inspection of large diameter pipes and pressure vessels - characterized in that the sensing member consists of a set of two separate coil-like structures and assemblies which are connected in series and structurally arranged above them. 3. MAG --- Uft - Magnetoinductive flaw detector for external inspection of small diameter pipes, pressure vessels and for internal inspection of large diameter pipes and pressure vessels - characterized by having a rotatable yoke of the magnetic circuit and the sensing element, allowing variable indication of various oriented defects ranging from transverse to longitudinally oriented defects. 4. MAG 'fcô - Magneto-inductive flaw detector for external inspection of small diameter pipes, pressure vessels and for internal inspection of large diameter pipes and pressure vessels - characterized by its swiveling carrier ensuring perfect adherence of the device to both the round and flat surface of the test item material. 5. MAG-TdL Magneto-inductive flaw detector for external inspection of small diameter pipes, pressure vessels and for internal inspection of large diameter pipes and pressure vessels - characterized by a segmented construction allowing perfect adaptation to the size and shape of the area to be inspected.