Исследование градуировочной характеристики турбинных преобразователей расхода жидкости типа MVTM

Most of the failures of turbine flow converters (TFC) used in the Russian system of main oil pipelines and oil product pipelines are caused by abrupt changes in the viscosity of the transported medium. In studies related to determination of the influence of the rheological properties of the pumped oil on the metrological characteristics of TFC that have a calibration curve in the form of a piecewise approximation without taking into account the correlation of TFC rotor speed with the viscosity of the pumped liquid in the flow rate subrange, the instability of the metrological characteristics in the operating range is observed. Taking into account the tendency to increase the volume of production and pumping of high-viscosity oils it can be assumed that the irregularity of the metrological characteristics of TFC, expressed in the change in the conversion factor will remain, which will negatively affect the reliability of accounting operations using oil quality control system (OQCS). Accordingly there is a need to maintain the error of TFC within the set limits in the subranges and throughout the entire range of flow rates. According to the results of the study performed by the authors it was confirmed that for the TFC of MVTM type the use of the calibration curve in the form of a piecewise-parabolic approximation with the dependence of the conversion factor on the ratio of TFC pulse frequency to the oil viscosity makes it possible to minimize the effect of changes in the parameters of the pumped medium on the measurement accuracy and as a consequence to stabilize the metrological characteristics of TFC in the recalibration interval, eliminate the costs of performing out-of-turn verifications, increase the accuracy and metrological reliability of the OQCS. Большинство отказов турбинных преобразователей расхода (ТПР), используемых в российской системе магистральных нефтепроводов и нефтепродуктопроводов, обусловлено резкими изменениями вязкости транспортируемой среды. В исследованиях по определению влияния реологических свойств перекачиваемой нефти на метрологические характеристики ТПР, имеющих градуировочную характеристику в виде кусочно-линейной аппроксимации без учета корреляции частоты вращения ротора ТПР с вязкостью перекачиваемой жидкости в поддиапазоне расхода, отмечается нестабильность метрологических характеристик в рабочем диапазоне. Учитывая тенденцию увеличения объема добычи и перекачки высоковязких нефтей, можно предположить, что непостоянность метрологических характеристик ТПР, выражаемая в изменении коэффициента преобразования, сохранится, что негативно скажется на достоверности учетных операций с применением систем измерений количества и показателей качества нефти (СИКН). Соответственно, возникает потребность в поддержании погрешности ТПР в установленных пределах в поддиапазонах и во всем диапазоне расходов. По результатам проведенного авторами исследования подтверждено, что для ТПР типа MVTM использование градуировочной характеристики в виде кусочно-параболической аппроксимации с зависимостью коэффициента преобразования от отношения частоты импульсов ТПР к вязкости нефти позволяет минимизировать влияние изменений параметров перекачиваемой среды на точность измерений и, как следствие, стабилизировать метрологические характеристики ТПР в межповерочном интервале, исключить затраты на выполнение внеочередных поверок, повысить точность и метрологическую надежность СИКН.

Measurement of Oil Consumption by Turbine Flow Meters in Conditions of Wax Deposition

Commercial metering of oil is performed at almost all stages of the life cycle, from well production control to the transfer of the produced oil to the end customer. In most cases, special systems for measuring the quantity and quality of commercial oil (SIQO) are used for this. If such a system implements an indirect dynamic measurement method, then a turbine flow meter is most often a means of measuring volumetric flow. Its accuracy depends on many external factors, including wax deposits on the inner surface of the measuring pipeline and on the elements of the flow meter itself. The article investigates the influence of the thickness of the paraffin layer on the error value of the turbine flow meter. It is shown that the decrease in metrological reliability occurs mainly due to the appearance of a paraffin layer in the measuring line itself. It is proposed to determine the timing of the metrological characteristics verification by indirect parameters, in particular, by the change in pressure in the measuring line.

Metrological support of maintenance by the technical state of communication means

Modern and prospective communication means are among the most knowledge-driven, high-tech types of industrial products, which are subject to enhanced requirements for quality and efficiency of application. The effective functioning of modern communication means is provided by built-in software, including metrological support. In this paper, we consider the specifics of metrological maintenance of large-scale communication facilities (tens and hundreds of thousands of elements) consisting of separate subunits, the serviceability, maintenance, and recovery of which can be performed autonomously. It is proposed to enhance the efficiency of the by-state-maintenance (also called maintenance by the technical state) by accounting for the specifics of metrological support, establishing an optimal sequence of operations, selecting the measuring instruments in accordance with relevant requirements. To do this, one has to use a combined indicator composed of individual parameters of the tests and the probability of their preferred choice. This allows to assess the technical condition of the communication means with a given probability during a minimal time. In addition, one can estimate the time of maintenance, taking into account the metrological reliability and the probability of correct evaluation of the result of checking the parameters by the measuring instruments. The order of implementation of the obtained results is formalized in the form of an algorithm and an example of their realization is presented.

Software and hardware module to support decision-making of qualitative abnormal changes presence in sample data based on information metrics

The key task of society development is to ensure rational use of natural resources and related continuous monitoring of natural and technical systems state. Regarding the growing problems of ensuring operational control of critical infrastructure facilities, tasks of epidemiological and environmental protection, solving the issues of developing new information technologies that meet modern requirements for scientific and practical activities and implementing their software and hardware modules for supporting decision-making on the presence of qualitative anomalous changes in monitoring data aimed at ensuring information and metrological reliability of control systems, becomes critical for the life support of the population. An information technology and a software and hardware module for supporting decision-making on the presence of qualitative abnormal changes in sample data, which are predictors of significant changes in the internal state of monitored objects, natural-technical systems or control devices, are proposed. A method for choosing parametric criteria for the difference in monitoring data using numerical measures of Shannon information entropy and Kullback-Leibler divergence is presented. The use of the developed and demonstrated in practice methodology makes it possible to achieve an increase in the accuracy, convergence and reproducibility of measurements through the use of numerical statistical modeling to obtain a numerical estimate of confident recognition boundaries of a qualitative anomalous change in the shape and shift of the sample distribution of monitoring data, including small samples.

Diagnostics of secondary power supplies means of communication

The article discusses an approach to technical diagnostics of secondary power supplies for communication facilities. Diagnostics is carried out during the current repair. This takes into account the features of the object being diagnosed, which affect the process of searching for defects. The purpose of the article is to analyze possible options for the development of diagnostic support for secondary power supplies. This takes into account the metrological reliability of measuring equipment. The probability of correct diagnosis is also calculated when searching for defects during routine repairs. Practically implemented recommendations for ensuring the required values of the indicators of the maintainability of communication facilities are substantiated. The possibility and expediency of using effective methods for diagnostics of secondary power supplies of communication facilities, which consider the sources as objects with many inputs, are shown. This allows the design to take into account the requirements for the maintainability of the product. During routine repairs, the time needed to search for defects is minimized. This is done through a rational choice of diagnostic procedures. When choosing, design features and conditions for restoring performance are taken into account. The proposed block diagram of the algorithm for choosing a diagnostic option minimizes the average recovery time of an object. A specific example of using the results obtained in the development of a conditional diagnostic algorithm for the power supply unit of the exciter and the radio receiver of an average power radio station is given. It is advisable to use the results obtained in the development of diagnostic support for promising communication facilities or in the improvement of existing communication facilities without additional costs.

КОНЦЕПТУАЛЬНИЙ ПІДХІД ДО МЕТРОЛОГІЧНОГО ЗАБЕЗПЕЧЕННЯ СТВОРЕННЯ КОМПОЗИТНИХ КОНСТРУКЦІЙ ЦИВІЛЬНИХ ЛІТАКІВ

A conceptual approach to the metrological support of the creation of composite structures for civil aircraft units has been developed and substantiated.It is shown that polymer composite materials currently occupy a significant place in the structures of civil aircraft and the volume of their effective use is constantly increasing, reaching in some cases 50% of the weight of the airframe, which indicates the relevance of the problem of metrological scientific support for creating structures of this class.The main goals of metrological assurance have been revealed, including the requirements for the uniformity and accuracy of measurements, the sufficiency and reliability of effective control, high quality measurements, as well as reducing the time and cost of research and experiments, metrological reliability, reducing the range of used measuring instruments, improving the safety of working conditions and environmental protection.At all stages (stages) of the existence of an aircraft, the effectiveness of structures made of PCM is ensured by various methods, methods and technical means of metrology. The main components of quality assurance are considered, which, being different in nature (process, property, form of conformity, set of devices, science), are integrated into a single system of concepts that form (ensure) the quality of an object.A block diagram of the main quality assurance tools is proposed, including certification, standardization, technical measurements, interchangeability and metro logic, as well as a block diagram of the general characteristics of the measurement quality. It is shown that these block diagrams together form the concept of scientific support for the creation of efficient structures of composite aircraft assemblies.It is proposed to form the development of this concept on the basis of the developed complex criterion for the effectiveness of the use of polymer composites in the environments of production, technological and scientific support.The structure of research is determined on the basis of the proposed conceptual approach to metrological support for the creation of composite structures of civil aircraft units at the main stages of their life cycle