V. E. Loskutov

Feasibilities of Using the ELCUT Software for Calculations in Nondestructive Testing

Examples of calculations of typical nondestructive testing problems with the use of the ELCUT 4.1 software designed for simulating the physical fields are given. A method which permits, using this software, to increase significantly the accuracy and the reproducibility of the results is proposed. The calculation results obtained using versions 4.1 and 4.2 of the ELCUT software are compared. It is shown that the calculations carried out with the use of versions 4.1 of the software distributed freely via the Internet makes it possible to establish the basic relations of the problems solved.

Irreversible changes in the magnetization as indicators of stressed-strained state of ferromagnetic objects

The changes in the magnetic properties of low-carbon steels connected with reversible and irreversible magnetization reversal processes under the action of elastic stresses are studied. It is shown that, on the curve of return from the coercive force, the maximal irreversible increment in the magnetization corresponds to the zero values of applied stresses. The application of compressive stresses leads to a sharp decrease in the irreversible component of the magnetization increment. Tensile stresses influence slightly the proportion between reversible and irreversible processes. New possibilities for the multiparametric quasi-static evaluation of stressed-strained states of ferromagnetic objects are revealed.

Current state of safety testing of main pipelines

The paper briefly describes the history of quality testing of buried main pipelines. The pioneering research into the development of magnetic techniques for detection of flaws caused by corrosion in pipelines has been conducted at the Institute of Metal Physics of the Ural Division of Russian Academy of Sciences. The fairly high accuracy of measured parameters of detected flaws is confirmed. The topical problems concerning pipeline testing are formulated.

Automated control of the velocity of in-tube diagnostic tools for main gas pipelines: II. Electronic equipment of a bypass device

The design and operation of electronic in-tube nondestructive-testing equipment containing a bypass device are described. The electronic equipment designed for the bypass device is built in the general system of onboard electronic equipment and performs automatic control of the preset velocity of a flaw detector or other diagnostic pigs moving through a pipeline.

In-tube nondestructive testing of main gas pipelines

A complex of auxiliary equipment for in-tube nondestructive testing of main gas pipelines (MGPs) via magnetic flaw detectors is described. A list and schedule of procedures for in-tube inspection of MGPs are presented. Typical flaws in the tube metal of MGPs are studied and classified by the degree of hazard.

Automated control of the velocity of in-tube diagnostic tools for main gas pipelines: I. Development, design, and operating principle of a bypass device

The study considers the development, design, and operating principle of a bypass device integrated into existing in-tube diagnostic tools. The bypass device is designed for automated control of the velocity of in-tube pig flaw detectors in main gas pipelines. Equipment of in-tube diagnostic tools with an automated-control system for the velocity provides performance of in-tube inspection without decreasing gas transportation. This facilitates the flaw detection of main pipelines substantially and makes a dispatcher of a gas-compressor station free of controlling the velocity of passage of in-tube diagnostic tools. The results of assembling a bypass device used for automated control of the velocity of in-tube diagnostic tools for main gas pipelines are considered. Arrangement of the bypass device in existing diagnostic tools for nondestructive testing is based on the experience of development, design, and exploitation of pig flaw detectors, which make it possible to locate the elements of the bypass device without any substantial restructuring of the pig flaw detectors.

A pig introscope for inspection of main gas pipelines

Development, design, and experimental testing of a new magnetic in-tube pig flaw detector is considered. An in-tube introscope makes it possible to obtain with photographic accuracy a direct image of the inner tube surface for assessment of internal flaws in pipelines.

Magnetic Field of a Circular Butt Weld of a Trunk Oil and Gas Pipeline

The results of computer simulation (using the ELCUT software) of the magnetic field of a weld of ferromagnetic pipes both in the weld body and from outside the weld are given. Both linear and nonlinear cases of magnetization are considered. It is shown that in the nonlinear case the magnetic permeability and induction in the weld body are extremely nonuniformly distributed over its thickness, i.e., different weld layers operate on significant different sections of the magnetization curve.

The quality control of underground gas pipelines via the electromagnetic and acoustic method

The modern development of the market economy in the face of competition imposes stringent requirements on the creation of materials and products. This applies particularly to such important industries as quality control of materials and the quality of underground pipelines. Long-term experience in the diagnostics of trunk pipelines has shown that apart from ordinary (classical) stress corrosion, defects occur with minimal disclosure of corrosion cracks. These stress-corrosion defects are practically not registered by previously used defectoscopes with longitudinal (DMT) and transverse (DMTP) magnetization systems. The Russian SPA Spetsneftegaz has designed and created an electromagnetic and acoustic contactless EMA defectoscope.

In-tube demagnetizing pig flaw detector

A method of in-tube demagnetization that can be realized using a demagnetizing magnetic plunger that passes through a tube and is driven by a transported product has been developed as a result of analysis of qualitative and quantitative characteristics of the demagnetization process.