Development and investigation restore technology of pump-compression tubes exhausted service life

В настоящее время существует проблема преждевременного разрушения насосно-компрессорных труб (НКТ) в условиях нефтедобычи в РФ. Основными причинами являются различные типы коррозии. С целью восстановления труб, исчерпавших эксплуатационный ресурс, предложена технология лейнирования НКТ внутренней тонкостенной трубой из коррозионностойкой стали. Технология позволяет производить композиционные трубы с высокими эксплуатационными характеристиками. Технология была испытана в полевых условиях, результаты испытаний показали высокую эффективность технологии лейнирования для решения проблем коррозионного разрушения НКТ.The problem of rapid failure of pump-compression tubes (PCT) exists under present conditions of oil production in the Russian Federation. Primary cause of this problem is different types of corrosion. To restore damaged tubes the technology using corrosion resistant steel inner pipe lining is offered. The technology allow to get composite tubes which have high servicing characteristics. The technology was tested under field conditions and the results of those tests showed high efficiency of the above lining method to solve the problem of PCT corrosion damage.Программа развития УрФУ на 2013 год (п.1.2.2.3

Improvement of manufacturing technology for thin-walled pipes made of copper alloys

Thin-walled pipes made of copper alloys - the brass grades L96, L68, L63, LANKMc; the bronze grade BrOF (the GOST state standard) are of great demand in aircraft, shipbuilding, automotive, defense, diesel and instrument-making industries. Pipe diameter ranges between 4.0 and 20 mm, and wall thickness is in the range from 0.1 to 0.6 mm. The manufacture of these pipes using traditional technological schemes is characterized by high labor input and low stability in providing quality characteristics, such as dimensional accuracy, the presence of surface defects and the level of mechanical properties. This study presents scientific evidence, new technological schemes developed for manufacturing pipes made of copper alloys with the use of the equipment and technology of multiple drawing on a long movable mandrel and results of their adoption at Revda Non-Ferrous Metal Processing Works JSC. © 2018 Trans Tech Publications, Switzerland.The study was made within the basic part of the state job in the field of scientific activity No. 11.9538.2017/BP; it was supported by Act 211 of the Government of the Russian Federation (agreement No. 02.A03.21.0006)

Rheological Properties and Microstructure of AlSi10Mg Aluminum Alloy produced by Selective Laser Melting

The present study is focused on rheological properties of AlSi10Mg aluminium alloy produced by selective laser melting (SLM) at temperatures of hot deformation with the aim to investigate the dependence of strain resistance on temperature, strain rate and strain degree. As-build cylindrical specimens made of AlSi10Mg aluminium alloy was examined on a cam plastometer in temperature range 20 - 500 °C, at strain rate ξ equal to 1, 10 s-1 up to strain degree e equal to 1.2. The paper presents results of study of initial microstructure, microhardness measurement and flow curves of AlSi10Mg alloy produced by SLM. The flow curves of AlSi10Mg alloy produced by SLM can be used in the computer simulation and development of new manufacturing methods of the metallic parts by additive technologies with the use of deformation post-treatment. © Published under licence by IOP Publishing Ltd.Government Council on Grants, Russian FederationThe study was made within the basic part of the state job in the field of scientific activity No. 11.9538.2017/8.9 and was supported by Act 211 of the Government of the Russian Federation (agreement No. 02.A03.21.0006)

Rheological Properties of Two-Phase Titanium Alloy VT23 under Hot Deformation in a Wide Temperature Range

The results of tests of two — phase titanium alloy VT23 on the plastometric complex IES UB RAS in the temperature range 700–1200 °C are presented, deformation curves are constructed. Peak values of stresses σs on deformation curves are identified, the microstructure of the alloy after different heating temperatures is studied.Представлены результаты испытаний двухфазного титанового сплава ВТ23 на пластометрическом комплексе ИМАШ УрО РАН в диапазоне температур 700–1200 °C, построены кривые деформирования. Выявлены пиковые значения напряжений σs на кривых деформирования, изучена структура сплава после различных температур нагрева

ИССЛЕДОВАНИЕ СОПРОТИВЛЕНИЯ ДЕФОРМАЦИИ ПОЛИКРИСТАЛЛИЧЕСКОГО ИРИДИЯ

Rheological properties of polycrystalline iridium of I 99.9 brand are investigated in order to construct the dependence of deformation resistance on studied factors (strain ratio, rate, and temperature). The tests of cylindrical samples made of iridium are performed using a cam plastometer in temperature range t = 900÷1400 °C at strain rates ξ = 0,2 and 20 s–1 as well as at t = 800÷1400 °C and ξ = 2 s–1 using the upsetting method at a strain rate up to 0,8. The results of investigations can be used to develop the pressure treatment of iridium wares at large plastic strains and in a broad range of thermomechanical parameters.Исследованы реологические свойства поликристаллического иридия марки И 99,9 с целью построения зависимости сопротивления деформации от исследуемых факторов (степени, скорости и температуры деформации). Испытания цилиндрических образцов из иридия проведены на кулачковом пластометре в интервале температур t = 900÷1400 °С при скоростях деформации ξ = 0,2 и 20 с–1, а также при t = 800÷1400 °С и ξ = 2 с–1 методом осадки со степенью деформации до 0,8. Результаты исследований могут быть использованы для разработки технологий обработки давлением изделий из иридия при больших пластических деформациях и в широком диапазоне термомеханических параметро

On ring deformation by internal pressure

Large-sized rings, manufactured by various methods of metal forming, are used in many industries. For the power industry, it is relevant to manufacture of retaining rings made of non-magnetic austenitic steel in order to strengthen the winding frontal parts of the rotors of turbine-type generators of a large unit capacity. In the process of generator operating, the retaining ring is one of the most loaded elements. As a result, material of retaining rings should have high strength properties, sufficient plasticity and good magnetic inductivity. Deformation of rings by internal pressure is the most promising and effective way of their cold hardening, providing a favorable and uniform stress-strain state of the metal in the manufacture of non-magnetic retaining rings for powerful turbine-type generators. Since the finished ring must acquire specific dimensions and a specified deformation degree in the process of cold hardening, the urgent task is calculation of the billet dimensions. The existing calculation procedure relies heavily on experimental manufacture data and is applicable only to a narrow range of rings, which reduces the accuracy of calculation and, ultimately, leads to an increase in ring allowances and a decrease in the metal utilization factor. In this research work a new technique for calculating the initial dimensions of rings, which is based on the incompressibility condition was developed and proposed. Taking into account the assumed boundary conditions, a system of two equations with three terms is compiled. To solve an incomplete equation system, it was suggested to introduce additional equations –in first version of the technique, the well-known solution of Nadai was used. In the second version –the condition of constancy of relative thickness of the ring wall permissible from the experimental data of deformation of rings of different sizes was used. The results of calculating the rings initial dimensions for both proposed techniques were compared with the experimental data. The maximum deviation from experimental data does not exceed 4% and the deviation average value does not exceed 1%, which indicates a sufficiently high accuracy of the proposed calculation techniques and the possibility of using them in manufacturing practice. © 2019, National University of Science and Technology MISIS. All rights reserved