Development of an electric linear actuator for shut-off and control valves

Перед ООО «НИИ Транснефть» и АО «ТОМЗЭЛ» была поставлена задача по разработке типоразмерного ряда электроприводов прямоходных, применяемых для управления клапанами запорно-регулирующими, с целью организации их серийного производства в России. При определении требований к разрабатываемой арматуре были учтены особенности эксплуатации ее импортных аналогов. Новые разработки должны были соответствовать общим техническим требованиям, требованиям безопасности и эргономики, предъявляемым к электроприводам, которые применяются на объектах трубопроводного транспорта нефти и нефтепродуктов. В процессе подготовки технических решений был проведен анализ тематических публикаций, международных и российских нормативных документов, технических характеристик электроприводов отечественного и зарубежного производства, существующих решений по схемам компоновки электроприводов блоками электронного управления. В рамках выполнения опытно-конструкторской работы были найдены оптимальные конструкционные решения, учитывающие фактические условия эксплуатации оборудования, разработана конструкторская документация на типоразмерный ряд электроприводов прямоходных, изготовлен опытный образец электропривода и успешно проведены его предварительные и приемочные испытания. The specialists of Pipeline Transport Institute LLC and TOMZEL JSC were tasked with developing a standardsize range of linear electric drives used to control shut-off and control valves in order to organize their serial domestic production. Operation features of its imported analogues were taken into account while determining the requirements for the developed equipment. New developments had to meet the general technical requirements, safety and ergonomics requirements for electric drives used at oil and oil products pipeline transportation facilities. In the process of preparing technical solutions, an analysis of thematic publications, international and Russian regulatory documents, technical characteristics of electric drives of domestic and foreign production, existing solutions for layouts of electric drives with electronic control units was carried out. As part of the development work, optimal design solutions were found, taking into account the actual operating conditions of the equipment, design documentation was developed for the standard-size range of linear electric drives, a prototype electric drive was manufactured and its preliminary and acceptance tests were successfully carried out.

Study on Asymmetry Concentration of Mixed Oil in Products Pipeline

Long-distance pipelines transporting multiple product oils such as gasoline, diesel and jet fuel, are important facilities for transporting fossil energy. One major concern in operation is the energy consumption of the pipeline. Energy consumption should be made optimized tracking batches of oils and cutting mixed oil, which requires an accurate prediction of concentration curve. In engineering, the concentration curve is usually assumed to be symmetric, but it is actually asymmetric, which may lead to estimation errors. Thus, the asymmetric concentration of mixed oil should be studied. The formation mechanism of the asymmetry of concentration curve has not been clearly clarified. A new method is proposed to measure the asymmetry of the concentration curve. Quantitative analysis is carried out for each factor on the asymmetry distribution of concentration curve. Based on the convection–diffusion equation, a modified oil-mixing model considering near wall adsorption effect is established. The model shows a good agreement with the Jablonski empirical formula. The error, compared with the experimental results, is less than 5%. The main findings are: (1) deviation volume has a negative correlation with pipe diameter and mean velocity; (2) adsorption coefficient has a greater impact on the length ratio of front and tail oil than diffusion coefficient; (3) the influence of all factors considered on the total length of mixed oil, front oil, tail oil and trail oil are basically the same; (4) if the limit of adsorption concentration in adsorption layer is 1, the reasonable value of adsorption coefficient a and b should be around 0.4. The results reveal the mechanism of asymmetric concentration of product oils and can provide practical suggestions to deal with the mixed oil.

Puddling Puddle Welds

Unique characteristics of individual pipelines come from over a century of evolving design, construction, maintenance, regulation and operation. These characteristics are especially true for legacy, pre-regulated pipelines. Due to the unique nature of the threats present on these assets, there is a need for unique inspection technologies and techniques that can increase pipeline integrity. Reconditioned and repaired pipe utilizing puddle weld repairs is one such threat. An advanced analysis was completed on a 10-inch, 68-mile light products pipeline. The pipeline was constructed with reconditioned pipe that was estimated to contain tens of thousands of puddle welds. Historical in-line inspection (ILI) data generally underperformed in classifying and discriminating puddle welds versus metal loss features. The primary objective of this project was to assess the probability of identification (POI) of a multiple dataset ILI tool utilizing multiple magnetic flux leakage (MFL) magnetization directions and residual (RES) magnetization measurements. A secondary objective was to scrutinize data for signs of coincident features. Hydrostatic testing failures showed that puddle welds with porosity and cracking were susceptible to failure and that the identification of these features would be beneficial. Analysis of historical puddle weld investigations and newly completed multiple dataset ILI data revealed strong identification capabilities in the RES dataset. The high-field magnetizations offered secondary confirmation but often saturated out thermal effects or material differences. The final report included over 40,000 identified puddle welds and five classifications for further investigation. Field investigations for 212 features were completed and the results compared to the ILI data to assess performance. A confusion matrix was created for true positive (TP), true negative (TN), false positive (FP) and false negative (FN) conditions. The smallest TP puddle weld dimension was 0.7″ × 0.7″, and the population had a statistical sensitivity value of 98% (132 TP and 3 FP). Three additional anomalies denoted as atypical were also investigated. The ILI signatures at these locations were consistent with previous repairs in which puddle welds with cracking were found and repaired. Two of the three features investigated were found to have cracking. Crack propagation was found to be both axial and non-axial in orientation. The results show that puddle welds can be detected and identified with extremely high accuracy. In addition, the preliminary classification results for atypical puddle welds show a high potential for identifying secondary coincident features. This paper details the stages, deliverables and results from an ILI advanced analysis focused on puddle welds.

Leak Rate Testing of a Natural Pipeline Defect

If a stable through wall defect (leak) were to occur in a pipeline, the leak rate is an important factor for both safety and environmental assessments, and also to determine the performance requirements for a leak detection system. For a “large” leak, an assessment can be based on simple idealization as an orifice, but for narrow crack like defects this is not appropriate. The flow through a crack is dependent on factors such as the surface roughness and the crack opening. These issues have been extensively studied for nuclear pipework where the fluid is either pressurized water, steam or CO2, and guidance is given in Annex F of BS 7910. However, there is little published work for pipeline geometries and single phase liquids such as refined hydrocarbons. This paper presents the results of experiments measuring the leak rates through a tight axial through wall crack in a NPS 8 refined products pipeline. Leak rate measurements were made using water (for safety reasons) over a range of pressures. The data were fitted to a model for leakage through a tight crack that takes account of interaction of asperities in surface roughness. The fitted equation was then adjusted to take account of the different density and viscosity of the pipeline products. It was concluded that the model was able to give a good prediction of the measured leak rates and that the adjustments for the product properties were small.

Development of a standard-size range of part-turn electric drives

Specialists of NII Transneft LLC and TOMZEL JSC were tasked with developing a standard-size range of partturn electric drives with an electronic control unit for ball shutoff valves in order to arrange the Russian production of this type of equipment. When determining the requirements for the developed valves, the features of the operation of foreign-made part-turn electric drives were taken into account. New developments had to meet general technical requirements, safety and ergonomics requirements for electric drives operated in oil and petroleum products pipeline transport facilities. When elaborating technical solutions, an analysis of thematic publications, international and Russian regulatory documents, technical characteristics of domestic and imported drives, existing solutions for the layout of electric drives with electronic control units has been accomplished. As part of the R&D work, optimal design solutions have been found taking into account the actual operating conditions of the equipment, design documentation has been developed for the standard-size range of part-turn electric drives, prototypes have been manufactured, and their preliminary and acceptance tests have been accomplished successfully.