Specifications TU Research Articles

Optimization of the content of isobutane in the feed stream of the plant for sulfuric acid alkylation of isobutane with olefins

The raw materials for the industrial production of moto- and air-alkylates are isobutane and butane-butylene fractions containing in their composition a component, n-butane, which is inert for the reaction of sulfuric acid alkylation of isobutane with olefins. In accordance with the Specifications TU 0272-024-00151638-99, the content of n-butane in the isobutane fraction, depending on the grade of the fraction, is 0.7÷20% wt. Its presence reduces the useful reaction volume of the alkylation reactor, and when separating the components of the alkylation reaction mass, it is necessary to use a distillation column (debutanizer). The possibility of including an additional column in the technological scheme for removing n-butane from the composition of the fraction (respectively, isobutane concentration) before it is fed into the alkylation reactor is being considered. This is of particular importance for factions with a brand below "High Brand". The study is conducted using the Honeywell UniSim Design software system. The Peng-Robinson method was used to calculate the properties of process stream components. The theoretically optimal design of the apparatus was calculated: when using a distillation column with a pressure in the apparatus of about 400 kPa to reduce the content of n-propane in the distillate (obtained isobutane fraction) to 0.001 mol. the share will require 48 theoretical plates, the accepted reflux ratio R = 8.9, the temperatures in the condenser and reboiler are 26.88 and 47.27 °C, respectively. A computational experiment has shown that in order to achieve the practical absence of n-butane in the obtained isobutane fraction (concentration of about 0.1% wt.), it is possible to use a distillation column with the following technological modes: the number of plates is 60, the feed plate is 15, the efficiency of contact devices is 0.8; the pressure in the column is about 400 kPa, the temperature in the condenser and reboiler is Тk=28.91÷29.05 ℃ and Тр=46.72÷47.25 ℃, respectively, reflux ratio R=20.41. This fraction also does not contain pentanes.

Mastering the production of special types of pipes made of ferritic-martensitic steels, taking into account the peculiarities of the microstructure and properties

The main results of the development of a technology for the production of special types of pipe products, carried out taking into account the features of the microstructure, the laws of phase and structural transformations, as well as the resistance to plastic deformation in a wide temperature range of steels of the ferritic-martensitic class of grades EP450-Sh and EP823-Sh, are presented. The microstructure was studied with determination of the grain size, the content of non-metallic inclusions and fraction of the main structural components depending on the heating temperature for quenching. Using the Gleeble 3800 multifunctional complex, the resistance to fracture deformation at high temperatures was determined. In the laboratory of JSC RusNITI, physical modeling of the cold rolling process in a two-roll stand was carried out according to the oval-oval calibration scheme in the mode of successive increase in reduction. On the basis of the studies carried out for the steel grades under study, were developed the modes for pressing stock hot-pressed pipes with dimensions of 133.0×14.0 and 89.0×7.0 mm; cold rolling of both large-scale samples of round pipes and stock pipes intended for subsequent production of hexagonal pipes; final heat treatment of pipes of round and hexagonal sections, ensuring compliance with the requirements of technical specifications. As part of the project direction, PJSC TMK developed and implemented, through inter-plant cooperation with JSC VTZ, TMK-INOKS Ltd. and JSC RusNITI, a new technology for manufacturing hexagonal pipes according to the hot pressing – cold deformation scheme (rolling, profiling), whereby large-scale samples of new types of pipes for special purposes were obtained from EP450-Sh and EP823-Sh steel grades. The results obtained are used to form a set of technical requirements for the new type of high-tech pipe products, presented in technical specifications TU 420-2021, TU 422-2021, TU 423–2021.

Досвід впровадження адитивних технологій при ремонті деталей ГТД зі сплава ЕП 648 ВІ (ХН50ВМТЮБ-ВІ) в умовах серійного виробництва

Technology has been developed for repairing the nozzle assembly (SA) casing in the D-18T engine by additively growing the damaged part by microplasma surfacing with a powder of EP648VI (KhN50VMTYUB-VI) alloy. Traditionally, a part with such damage was rejected. The cost of replacing a damaged part with a new one is about 200 thousand hryvnias. The article discusses the equipment and features of the growing technology using the method of microplasma multilayer surfacing. Additive growth of the cut-damaged part was carried out on a STARWELD 190 H robotic installation for microplasma powder surfacing using EP648 VI alloy powders with a 63–163 micron fraction. After growing, heat treatment (aging at 700 ºС, exposure for 16 hours), mechanical processing, and quality control of the grown part were carried out. To create an evidence base to determine the possibility of installing a repaired part on the engine, a set of studies was carried out, which included the determination of the chemical composition of samples grown using a technology similar to repair, metallographic studies, and mechanical tests. As a result, it was found that the chemical composition of the deposited metal meets the requirements of the technical specifications TU 14-1-3046-97 "Bars made of heat-resistant alloy grade KhN50VMTYUB (EP648), and the microstructure of the deposited metal after heat treatment is a γ - solid solution with the presence of carbides, carbonitrides and a small amount of γ´ phase, which corresponds to the normally heat-treated state of the EP 648 VI (KhN50VMTYUB-VI) alloy and the level of mechanical properties of the grown alloy with subsequent serial heat treatment (aging at 700 ° C, holding for 16 hours) not lower than the level of the forging used at serial production of a part. The economic effect of the introduction of this technology is shown, which is more than 100 thousand hryvnias (about 23% of the cost of a new part).

Research of modification influence on cracking resistance of cast iron in moulds

The research is devoted to determination of influence of grey iron modification technology; this gray iron is used for manufacture of steel casting moulds. Difficult operating conditions stipulate strict requirements both on construction of moulds and on their materials. These moulds materials should reliably withstand to effect of cast steel with the temperature 1600–1700 °C, as well as to thermal shock which is directly proportional to this temperature, to essential cyclic thermal stresses and deformations. Peculiar operating conditions of moulds (such as high heating temperature, mounting on movable and stationary runners, intensive traffic routes etc.) hamper conduction of the required investigations directly during their operation. The research was carried out on physical models of moulds for consumable electrodes of vacuum arc remelting with geometrical similarity scale 1:10. The following mould models for consumable electrodes, cast of iron, were tested: modified by ferrosilicon FS65 (according to the GOST 1415-93), modified by primary aluminium A99 (according to the GOST 11069-2001), modified by vanadium slag ShVD-1 (according to the technical specification TU 14-11-178-86), modified by ferrosilicobarium FSB-30 and by silicomishmetal SIMISh-1. These modifiers were selected owing to their wide use at production facilities. Thereby, the conducted tests were aimed to examine the features of moulds walls deformation and stress-strain state on the models of gray and modified cast iron; they allowed to assess the advantages and disadvantages of obtained structure and graphite inclusions forms. They will also help to develop the most rational form of external surface for moulds designed for section and sheet metal, previously determining destruction features. Application of thinwalled moulds with rational form can provide substantial decrease of their specific consumption. Examination of metal quality which was cast in pilot (lightened) moulds with curved external surface displayed that metal macrostructure for pilot and usual ingots is the same.

Assessment of influence of disperse filler polarity on structure and water absorption of epoxy compositions

Introduction. Composite materials on the basis of epoxy resin find wide application as adhesives, coatings and structural materials whose properties it is possible to regulate by introduction of various additives including disperse fillers in the epoxy binder. Positively influencing properties of epoxy materials, the disperse fillers can reduce water resistance of the materials. This work is aimed at studying of influence of polar and nonpolar disperse fillers on structure and water absorption of the epoxy materials. Materials and methods. When obtaining composite materials, the following components were used: ED-20 epoxy resin (state standard GOST 10587-84), dibutylphthalate (state standard GOST 8728-88) plasticizer, polyethylenepolyamine (specification TU 2413-357-00203447-99) hardener, marshallite (state standard GOST 9077-82) and graphite (state standard GOST 17022-81) disperse fillers. The structure of samples was investigated by means of IR-spectroscopy method. Water absorption was determined in boiling water using the standard gravimetric method (state standard GOST 4650-2014 (ISO 62:2008)) and evaluated by sample mass variation within 120 days. Results. As a result of the conducted researches, the optimum content of the marshallite and graphite fillers in epoxy materials is established. When mass filler-to-binder ratio is equal to 15/85, water absorption of the materials is minimum. The IR-spectroscopy method showed that introduction of the marshallite polar filler in the epoxy binder promotes ordering of material structure due to formation of hydrogen bond between reactive groups of the filler and resin. Localizing in amorphous areas, particles of the graphite nonpolar filler lead to weakening of the hydrogen-bond system. Interaction of marshallite-filled samples with water is accomplished at the swelling mode, with equilibrium degree of swelling about 1 %. The mechanism of interaction of graphite-filled samples with water includes the alternating stages of dissolution and swelling, which are more expressed as compared with check samples. Conclusions. Water resistance of epoxy materials filled with disperse fillers is defined by a microstructure of the cured resin. Introduction of the marshallite polar filler in the epoxy binder leads to ordering of material structure that results in increasing of water absorption. Introduction of the graphite nonpolar filler in the epoxy binder leads to disordering of material structure that results in reducing of water absorption. Lower value of water absorption of graphite-filled epoxy material is connected with partial dissolution of the sample. Using nonpolar fillers is inexpedient for epoxy materials contacting with water.

Performance of Surface Layers Applied by New Powder Wire in Highly Abrasive Wear

The influence of chromium (in high concentrations) as a reducing agent in the manufacture of Fe–C–Si–Mn–Cr–Ni–Mo powder wire is studied. Metal layers are applied to St3 steel plates under An-26S flux, with preliminary heating of the basic metal to 250–300°C. Powder wire (diameter 5 mm) manufactured on a laboratory machine is applied by means of an ASAW-1250 welding system, in the following conditions: current 420–520 A; voltage 28–32 V; welding rate 7.2–9.0 m/h. After surfacing, the metal is cooled to room temperature. In producing the powder wire, the filler consists of PZhV1 iron powder (State Standard GOST 9849–86); FS75 ferrosilicon powder (State Standard GOST 1415–93); FKh900A high-carbon ferrochrome powder (State Standard GOST 4757–91); FMn78(A) carbon ferromanganese (State Standard GOST 4755–91); PNK-1L5 nickel powder (State Standard GOST 9722–97); FMo60 ferromolybdenum powder (State Standard GOST 4759–91); FV50U0.6 ferrovanadium powder (State Standard GOST 27130–94); PK-1U cobalt powder (State Standard GOST 9721–79); and PVN tungsten powder (Technical Specifications TU 48-19-72–92). Within the chosen concentration ranges, carbon, manganese, chromium, molybdenum, nickel, and to some extent vanadium increase the hardness of the applied layer and also decrease the wear rate of the samples. The low viscosity of the matrix prevents the retention of tungsten carbide at the surface. Consequently, wear occurs not by uniform abrasion of the surface but by the extraction of high-strength carbon particles from the matrix. As a result, new cracks are formed in the matrix, which accelerates its wear. Multifactorial correlational analysis yields dependences of the hardness and wear resistance of the applied layer on the mass content of the elements in the Fe–C–Si–Mn–Cr–Ni–Mo powder wire. These dependences may be used to predict the hardness and wear resistance of the applied layer with change in its chemical composition.

Stabilization of Self-slaking Slags from Ferroalloy Production

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Reduction of Tungsten from Its Oxide in Surfacing by Means of Powder-Core Wire

The influence of introducing tungsten and tungsten concentrate in powder-core wire on the structure, microhardness of the structural components, hardness, and wear of the applied metal layer is studied. For surfacing, tungsten-bearing powder wire (types H and E in the IIW classification) is produced in the laboratory. The fillers employed are KR-1 silicon powder (State Standard GOST 2169–69); MR-0 manganese powder (State Standard GOST 6008–82); PKhA-1M chromium powder (Technical Specifications TU 14-1-1474–75); VEL-1 vanadium (Technical Specifications TU 48-0533–71); PNK-1L5 nickel (State Standard GOST 9722–97); PAP-1 aluminum (State Standard GOST 5494–95); PVT tungsten (Technical Specifications TU 48-19-72–92); and PZhV-1 iron powder (State Standard GOST 0489–96). In some wire, tungsten powder is replaced by KSh-4 tungsten concentrate (State Standard GOST 213–83), produced by OAO GK AIR. The carbon-bearing reducing agent employed is gas-purification dust from aluminum production. Its composition is as follows: 21.00–43.27 wt % Al2O3, 18–27 wt % F, 8–13 wt % Na2O, 0.4–6.0 wt % K2O, 0.7–2.1 wt % CaO, 0.50–2.48 wt % SiO2, 2.1–2.3 wt % Fe2O3; 12.5–28.2 wt % Ctot; 0.03–0.90 wt % MnO, 0.04–0.90 wt % MgO, 0.09–0.46 wt % S, and 0.10–0.18 wt % P. The wire (diameter 5 mm) is produced on laboratory equipment. An ASAW 1250 system is used for surfacing, in the following conditions: Is = 400–450 A; Uarc = 32–36 V; Vs = 24–30 m/h. In surfacing, five metal layers are applied, under a layer of AN-26S flux and flux based on slag from silicomanganese production. The chemical composition of the applied metal is determined, and metallographic data are obtained: the size of the former austenite grain, the size of the martensite needles, and the content of nonmetallic inclusions are determined. Wear tests are conducted, and the hardness and microhardness are measured. The use of tungsten concentrate instead of tungsten powder in surfacing is shown to be possible in principle. The degree of tungsten extraction is calculated. For type-H wire, the replacement of tungsten powder by tungsten concentrate does not increase the content of nonmetallic inclusions in the metal layers applied; the primary austenite grain size is decreased. For type-E wire, the use of tungsten concentrate tends to decrease the primary austenite grain size and the size of the martensite needles and also increases the microhardness of martensite within the applied layer. The replacement of tungsten powder by tungsten concentrate in class-H wire considerably increases the hardness and wear resistance of the applied layer.

Flux-Cored Wire for the Surfacing of Parts Subject to Wear

Flux-cored wire of Fe–C–Si–Mn–Cr–Ni–Mo composition (type A in the International Institute of Welding classification) is developed for the surfacing of abrasively worn parts. In the laboratory, multiple surface layers are applied to plate samples, with preliminary heating to 350°C and subsequent (after surfacing) slow cooling. An ASAW-1250 welding tool with the new wire is used for surfacing: six layers are applied to a 09Г2С steel plate. Instead of amorphous carbon, the wire consists of dust containing carbon and fluorine, with the following composition: 21–46% Al2O3, 18–27% F, 8–15% Na2O, 0.4–6.0% K2O, 0.7–2.3% CaO, 0.5–2.5% SiO2, 2.1–3.3% Fe2O3, 12.5–30.2% Ctot, 0.07–0.90% MnO, 0.06–0.90% MgO, 0.09–0.19% S, and 0.10–0.18% P. The filler is a powder: PZhV1 iron powder (State Standard GOST 9849–86); FS75 ferrosilicon powder (State Standard GOST 1415–93); FKh900A high-carbon ferrochrome powder (State Standard GOST 4757–91); FMn78(A) carbon ferromanganese powder (State Standard GOST 4755–91); PNK-1L5 nickel powder (State Standard GOST 9722–97); FMo60 ferromolybdenum powder (State Standard GOST 4759–91); FV50U0.6 ferrovanadium powder (State Standard GOST 27130–94); PK-1U cobalt powder (State Standard GOST 9721–79); and PVN tungsten powder (Technical Specifications TU 48-19-72–92). Analysis of the applied layer shows that, within the ranges studied, carbon, chromium, molybdenum, nickel, manganese and, to a small extent, vanadium both increase the surface hardness and slow sample wear. Increasing the tungsten concentration somewhat increases the surface hardness but decreases the wear resistance. The low ductility of the matrix prevents the retention of tungsten carbides at the surface and so, rather than uniform surface wear, what is observed is crumbling of strong carbide particles from the matrix, with the formation of cracks that facilitate additional wear. The introduction of cobalt in the batch does not markedly affect the hardness and surface wear: the matrix obtained is more ductile but less hard. With no hard carbide particles in the matrix, the introduction of cobalt is deleterious. Multifactorial correlation analysis yields dependences of the hardness and wear resistance of the applied layer on the content of elements in the Fe‒C–Si–Mn–Cr–Mo–Ni–V–Co flux-cored wire.

Quality of the Seam in Welding under Flux by Means of Barium–Strontium Carbonatite

The use of barium–strontium carbonatite in the modification and refining of ferrocarbon alloys is considered. Its use in welding fluxes is proposed. That possibility is analyzed for the example of BSK-2 barium–strontium modifier (Technical Specifications TU 1717-001-75073896–2005) produced by OOO NPK Metalltekhnoprom, with the following composition: 13.0–19.0% BaO, 3.5–7.5% SrO, 17.5–25.5% CaO, 19.8–29.8% SiO2, 0.7–1.1% MgO, 2.5–3.5% K2O, 1.0–2.0% Na2O, 1.5–6.5% Fe2O3, 0–0.4% MnO, 1.9–3.9% Al2O3, 0.7–1.1% TiO2, and 16.0–20.0% CO2. A production technology is proposed for a flux additive containing 70% barium–strontium carbonatite and 30% liquid glass. Several welding-flux compositions based on slag from silicomanganese production are tested. The flux additive is introduced in quantities of 1, 3, and 5%. The specifics of welding under the proposed welding fluxes are determined. The chemical composition of the fluxes, the slag crusts, and the metal in the weld seam are determined by X-ray spectral analysis. The weld seams are studied metallographically. It is possible in principle to use barium–strontium carbonatite as a refining additive to welding fluxes; it also provides a protective atmosphere for the welded metal. By introducing barium–strontium carbonatite, the content of nonmetallic inclusions (nondeforming silicates, point oxides, and brittle silicates) in the weld seam may be reduced, and the desulfurizing properties of the welding fluxes may be enhanced. The introduction of up to 5% barium–strontium carbonatite in welding fluxes based on silicomanganese slag ensures that the metal in the weld seam has ferrite–pearlite structure of Widmanstatten type. The grain size is slightly reduced here: from a score of 4 to 4–5.

Glass-filled polyurethane materials produced by fiber composite spraying

By using polymer composites in auto parts, the vehicle mass may be considerably reduced, with improvement in the dynamic properties and load capacity of the vehicle and also in its fuel consumption and tailpipe emissions. In the present work, recommendations are made for improving the performance of glassfilled polyurethane materials produced by fiber composite spraying. To that end, the thermal stability, impact strength, high-temperature strength, and Shore D hardness are determined in accordance with Technical Specifications TU 2292-010-14682925–2014. The sound absorption and UV resistance of the composites are also determined.

Розрахунок рецептур та розробка технологічної схеми виробництва альбумінового сиру «Урда» для промислових підприємств

Виробництво сиру «Урда» у промислових умовах може зайняти вагоме місце в асортиментному ряді молочних продуктів, оскільки сир має високі біологічну цінність та смакові якості. Одержання сиру «Урда» залежить від кількості свіжої овечої молочної сироватки. Відомо, що з 10 дм3 овечого молока можна отримати 450…500 г сиру «Урда», тому що такий продукт виготовляють виключно з овечої сироватки. Він є значно дорожчим порівняно з іншими видами сиру. Однак, використавши як додаткову сировину сироватку з коров’ячого молока, можна значно здешевити вартість готового продукту, а також раціонально використати вторинну сировину, що утворюється при виробництві сирів із коров’ячого і овечого молока. У статті запропоновано науково обґрунтовані рецептури для виробництва альбумінового сиру «Урда»; розроблено технологічну схему виробництва продукту. Технологія альбумінового сиру «Урда» пройшла промислову апробацію на ПАТ «Ковельмолоко», м. Ковель. На продукт розроблено технічні умови ТУУ 01.4-00492990-004:2014. В основі розрахунку рецептур альбумінового сиру «Урда» було проведення експериментальних досліджень, які дали можливість визначити раціональне співвідношення овечої та коров’ячої сироваток для виробництва продукту. Встановлено, що для виробництва сиру «Урда» можна використовувати суміші сироваток (овеча:коров’яча) у співвідношеннях 1:1 та 3:1. Розроблена технологія альбумінового сиру «Урда» може бути впроваджена на молокопереробному підприємстві, де налагоджено випуск твердих сичужних сирів і розсольного сиру бринза. Впровадження нової технології не потребує великих виробничих площ, дороговартісного обладнання і додаткового переоснащення виробництва. Виробництво альбумінового сиру «Урда» може бути реалізовано на діючих виробничих площах паралельно з випуском основної продукції.

Electrowelded straight-seam high-strength pipe for structural use

Technical Specifications TU 1381-068-00186654–2016 have been developed for large-diameter electrowelded straight-seam high-strength pipe used in special-purpose structures, including those that operate in severe climatic conditions. Pipe made from thick sheet with a low impurity content by thermomechanical rolling with accelerated cooling is characterized by low-temperature strength, crack resistance, thermal stability, and resistance to fatigue-crack propagation. Such pipe resists mechanical aging and withstands seismic shocks. Research data permit the formulation of Technical Specifications TU 1381-068-00186654–2016 such that the special-purpose structures made from electrowelded straight-seam pipe will operate reliably.

Operation of imported rail on the East Siberian Railroad

Japanese R65 rail is metallographically analyzed after operation in the East Siberian Railroad. Its chemical composition complies with Technical Specifications TU 0921-239-01124323–2007 for the steel used in the production of 350LDT rail. The macrostructure of the metal is of satisfactory quality. The tensile mechanical properties, hardness, and impact strength at +20°C determined on samples from the nonoperational chamfer of the rail head are consistent with Technical Specifications TU 0921-239-01124323–2007 for the steel used in the production of 350LDT rail. The impact strength at negative temperatures does meet the corresponding requirements. The content of nonmetallic inclusions is low. However, exogenous inclusions are present at unacceptable levels. The microstructure of the Japanese rail sample consists of sorbite and plate pearlite, whose dispersity declines on moving away from the surface. In operation of the rail, thin inclined cracks (depth 1.1 mm) form at the surface of the working chamfer in the rail head; in addition, lateral wear is considerable (up to 15 mm).

MODERNIZATION AS A WAY TO IMPROVE THE USE OF UNIVERSAL CARS

Purpose. The main design requirements of the modernized cars are those allowing reduction of operating costs and improvement of economic efficiency of their use. Due to the relevance of this subject the work presents the complex of conducted research, which will allow in prospect to use the universal flatcar, converted according to the Technical specifications TU 3182-065-71390252-2911 for container service. The research includes: evaluation of strength, fatigue safety of the design elements and conformity assessment of the strength characteristics of the modernized flatcar elements to the regulatory documents. Methodology. The analysis covers the use of specialized and universal rolling stock for transportation of containers, as well as the issues of modernization of universal cars. The strength of the flatcar bearing structure is evaluated based on the complex of numerical and experimental studies. The experimental part includes the static, repair load and impact tests. The car strength qualities and the fatigue safety are evaluated on the basis of calculated and experimental data. Findings. The conducted static, repair load and impact tests, given the quasi-static longitudinal forces, allowed the evaluation of the car structure strength according to the regulatory documents. The calculated and experimental data make it possible to assess the fatigue safety of structural elements. The present work is completed by obtaining the results that allow performing reasonable re-equipment of universal flatcars with baseplates with fitting stops to fasten the containers. Originality. The results of calculated and experimental studies showed that the modernized flatcars meet the conditions of strength and have sufficient fatigue safety factor. This makes it possible to recommend the re-equipment of universal flatcars for all car-repair enterprises that submitted the prototypes. Practical value. The complex of works was conducted that demonstrated the possibility of re-equipment of universal flatcars for the transportation of large containers. Part of the car fleet, kept in reserve, with little material costs can be transferred to the operational fleet. The modernization – re-equipment of universal flatcars with stationary specialized devices will increase the car usability coefficient.

Production of hexahedral pipe blanks from centrifugally cast 04Х14ТЗР1Ф (СЧ82) steel billet for the nuclear industry

A new production technology for centrifugally cast 04Х14ТЗР1Ф boron-steel has been developed. In addition, technology has been developed for the production of hot-rolled 290 × 12 mm pipe from such blanks on a TPU 8-16″ system with Pilger mills and for the conversion of such pipe to hexahedral pipe blanks (dimensions 257 +2/–3 × 6 +2/–1 × 4300 +80/–30 mm). The hexahedral pipe blanks produced by this means meet the requirements on the geometric dimensions, mechanical properties, and intercrystallite corrosion in Technical Specifications TU 14-3-1630–89 for the manufacture of racks used in holding tanks at nuclear power plants and in spent-fuel transportation.

Production of seamless pipe in a pilger mill with new groove configurations

New groove configurations for the pilger mill reduce the nonuniformity of sleeve deformation on transition from the striker to the polishing section and enhance pipe quality. The rolling of 08X18H10Tsteel-Ш pipe blanks (produced by electroslag remelting) by the new method to obtain intermediate pipes is considered. Machining of the intermediate pipes—boring and turning—produces commercial pipe of diameter 530 and 630 mm corresponding to Technical Specifications TU 14-3R-197–2001.

Dehydration of the still residue from the rectification of raw benzene

The still residue from the rectification of raw benzene is a stable emulsion with a water content exceeding 60%. Until 2012, it was dehydrated in the department of coumarone–indene resins by vacuum distillation. The closing of that department entailed the development of an alternative technology, which consists of two stages: 1) addition of 20–25% of the benzene fraction to the still residue and the removal of the water that settles in the lower layer; 2) distillation of the benzene and residual water by the heat from spent steam. After dehydration, the still residue contains 0.5–3.0% water and complies with Technological Specifications TU 2415-194-00190437. This technology permits the processing of the waste from the tar-distillation department in the stills of the benzene department—in particular, light distillates from the naphthalene column (containing naphthalene and 40–60% water) and light oil of no commercial value that contains phenolic hydrocarbons, resin-forming compounds, and phenols. After adding 10–15% of such wastes to the raw still residue, the mixture is dehydrated by the proposed technology. The introduction of such wastes in the still residue prior to dehydration permits the additional production of up to 4 t phenolic hydrocarbons and 40 t of commercial products such as coal solvent naphtha and coumarone–indene resin each month.

Regulating the macrostructure of continuous-cast billet

The macrostructure of 10, 20, 09Γ2C, and дб steel billet (diameter 150 and 220 mm) is investigated. Regardless of the casting parameters and grade of steel, the metal in the continuous-cast billet studied contains sections distributed randomly over the length that are characterized by impermissible central porosity in tests. The nonuniform distribution of this defect over the length of the billet is due to unstable solidification of the central zone and is not eliminated in continuous casting of the steel. The research permits the adoption of a new edition of Technical Specifications TU 14-159-324-2012 for continuous-cast billet, with requirements on the extent of the central porosity.

Nanodiamonds effect on characteristics of copper galvanic coatings

The introduction of nanodiamonds (Technical Specification TU 3974-001-10172699-94) into a sulfuric acid electrolyte of copper plating was shown to result in decreased porosity and the corresponding diminishing of the electric resistance of the copper coatings.