Electroslag Surfacing Research Articles

RESTORATION OF LARGE MODULAR TEETH OF BALL MILL GEARS BY ELECTRO-SLAG SURFACE

This article is devoted to researching the possibility of restoring straight-toothed large-module gears by electro-slag surfacing of individual defective teeth. During the work, an installation was designed and manufactured to restore gears that do not require further machining. A comparative analysis of the proposed technology with the traditional surfacing technique was carried out, paying attention to variables such as the composition of the surfacing material used, process parameters, stabilization of the electro-slag process, and ensuring the geometric dimensions and profile of the tooth. The study results demonstrate that the proposed technology provides higher hardness and wear resistance of remanufactured parts compared to traditional methods.

ВПЛИВ СТРУМОПІДВОДУ НА ЕЛЕКТРОМАГНІТНІ ПРОЦЕСИ В КРИСТАЛІЗАТОРІ ДЛЯ ЕЛЕКТРОШЛАКОВОГО НАПЛАВЛЕННЯ МЕТАЛ

The results of numerical modeling of electromagnetic processes in the system of electroslag surfacing of metal with sectional mould for different positions of the terminals of the current supply, which is made on the basis of the devel-oped mathematical model. The results are presented in the form of current density distributions in the metal of section with a vertical slit and electromagnetic forces in the liquid slag. It is shown that the azimuth displacement of the upper terminal of the mould, which is connected to the current-carrying section relative to its vertical slit, significantly affects the electromagnetic forces in the slag bath but does not change the heat output in the system. At the same time, the position of the lower terminal connected to the workpiece has virtually no effect not only on heat dissipation but also on the forces in the liquid slag. Ref. 6, fig. 2, table.

МОДЕЛЮВАННЯ ЕЛЕКТРОМАГНІТНИХ ПРОЦЕСІВ В СЕКЦІЙНОМУ КРИСТАЛІЗАТОРІ ДЛЯ ЕЛЕКТРОШЛАКОВОГО НАПЛАВЛЕННЯ МЕТАЛУ

A three-dimensional mathematical model for the study of electromagnetic processes occurring in a sectional current-supply crystallizer during electroslag surfacing of metal is presented. Numerical simulations of the electromagnetic field in such system were performed, the distributions of electric current density, volumetric heat emissions in the system elements, as well as the distribution of electromagnetic forces in liquid slag were obtained. The comparison of calculated and experimental values of the integral parameters of the specified system is carried out. References 8, tables 2, figures 5.

УДОСКОНАЛЕННЯ ЕЛЕКТРОШЛАКОВОГО НАПЛАВЛЕННЯ ХРОМИСТИХ ЧАВУНІВ

The main disadvantages of the existing methods of improving the strength of coatings, including the use of electroslag surfacing, on existing equipment structures to implement this process are considered. The task is to significantly improve the process of elec-troslag surfacing to ensure the desired operational strength of the coating and thus ensure the absence of cracks in the metal.It is shown that electroslag surfacing of chromium cast irons allowsto significantly improve their mechanical properties, in particular strength and to obtain defect-free high-quality welded metal for operational requirements. The use of current-carrying crystallizer expands the possibilities of use in the surfacing of different types of surfacing materials and regulating the structure and properties of the weld metal. The industrial experience of electroslag surfacing in the current-carrying crys-tallizer of rolled rolls with the use of chromium cast iron in the form of fractions and liquid additives, including chromium cast iron, is presented. A new direction in the development of surfacing works is shown -obtaining flat bimetallic blanks designed to strengthen fast-wearing surfaces.It is emphasized that a significant advantage of the current-carrying mold is its sectional design.Various schemes of realization of electroshack surfacing process both two-section and three-section with their features and definition with definition of the basic advantages and lacks are presented.This technology is quite promising and effective and can be proposed for wider implementation, due to the fact that there are relatively simple ways to implement surfacing.

Electroslag surfacing of chromium cast irons in current-carrying mould

It is shown that electroslag surfacing of chromium cast irons can significantly improve their mechanical properties and obtain defect-free quality weld metal. The use of current-carrying mould expands the possibilities for using of different types of surfacing materials and regulating of the structure and properties of the deposited metal. Industrial experience of electroslag surfacing in the current-carrying mould of rolling rolls with chromium cast iron in the form of shot and liquid additive is presented. New direction in the development of surfacing work — obtaining of flat bimetallic billets designed for the hardening of wear surfaces is shown.

Electroslag surfacing of 110G13L steel using various types of surfacing materials

ABSTRACT Electroslag surfacing was performed in a 180 mm current-conducting mould on 110G13L steel billets using shavings and electrodes from the same steel grade as a remelted material. It has been established that for any type of surfacing material, the structure of the deposited metal is austenitic. It is shown that the use of electroslag facing with chips allows to obtain a lower penetration of the base metal in comparison with electrode surfacing. The most dangerous area for the appearance of microcracks is the zone of fusion of the base and deposited metals, the width of which depends on the technology of surfacing and, accordingly, the power of thermal action on the base metal.

Виготовлення електрошлаковим наплавленням ударної частини молотків механізму струшування електрофільтрів

The expediency and relevance of the development of technological solutions that make it possible to increase the efficiency of electric precipitation filters, which are the main gas cleaning equipment at thermal power plants, metallurgical and cement industries, have been considered. It is recommended to improve the operation of the shake mechanism of the electrical precipitator by forming the impact part of the hammer with a material resistant to plastic deformation under impact loads and provides a minimum and constant area of impact contact of the hammer with the shaking anvil beam throughout the life cycle. Review and analysis of publications in the field of surfacing revealed the lack of data on the properties of the proposed material deposited by electroslag method, as well as its use in the impact mechanisms of electrical precipitators. The impact part of the hammer was made of the proposed material by electroslag surfacing in a special detachable copper water-cooled mold with a powder electrode. The structure and properties of the metal of the hardened part of the hammer have been studied. As a result, it has been found that the chemical composition of the metal of the deposited impact part of the hammer is close to the composition of the metal deposited with the OZN-300M electrodes with a low content of sulfur and phosphorus; this being due to the effect of refining in electroslag remelting. The surfacing process provides the formation of a tight monolithic, homogeneous dispersed and defect-free structure characteristic of cast electroslag metal. In the cast metal, the presence of non-metallic inclusions of predominantly globular shape with a characteristic average size of 2.5-4.5 μm in the form of oxides and sulfides with a volume percentage (0.60-0.70)×10-2 and (0.51-0.60)×10-2, respectively has been revealed

Research of corrosion-resistant welding of NPP equipment performed with a strip electrode by arc and electroslag methods

This article presents the results of studies of corrosion-resistant surfacing with a strip electrode under a layer of flux on carbon steel, performed by arc and electroslag methods. The similarity of the chemical composition, structure, mechanical and corrosion characteristics of the deposited metal in both cases is estab- lished. It has been shown that electroslag surfacing provides greater purity for non-metallic inclusions.

ЗАСТОСУВАННЯ ЕЛЕКТРОШЛАКОВОГО НАПЛАВЛЕННЯ ДЛЯ ВИГОТОВЛЕННЯ МОЛОТКІВ УДАРНОГО МЕХАНІЗМУ СТРУШУВАННЯ ОСАДЖУВАЛЬНИХ ЕЛЕКТРОДІВ ЕЛЕКТРОФІЛЬТРІВ

У статті представлено основні дані про технологічні можливості виготовлення деталей для ударного механізму струшування осаджувальних електродів електрофільтрів. Запропоновано й аналітично обґрунтовано перспективність зміни технологічного процесу виготовлення молотка ударного механізму з метою максимального збільшення коефіцієнта корисної дії електрофільтру при одночасному збільшенні експлуатаційної надійності молотків і зниженні вартості їх виробництва. Встановлено, що процес виготовлення молотка практично можна звести до однієї операції – електрошлакового наплавлення. Водночас для вихідних заготовок (хвостовик і витратний електрод) застосовуються стандартні стали стандартного сортаменту. В результаті дослідження якості металу наплавленої ударної частини молотка встановлено, що процес електрошлакового наплавлення забезпечує формування монолітної і бездефектної структури; мікроструктура наплавленого металу – ферито-перлітна, досить однорідна і дисперсна, що характерно для литого металу в водоохолоджуваному кристалізаторі. Ударнівипробування молотків, отриманих з використанням електрошлакового наплавлення, проводили на спеціальному ударному стенді, який забезпечує енерго-кінематичні параметри удару молотка по балці струшування, аналогічні промисловому електрофільтру. Випробування показали їх високу надійність (руйнувань не було) і тим самим підтвердили можливість їх промислового застосування. Розрахований очікуваний економічний ефект від застосування технології електрошлакового наплавлення при виготовленні молотків ударного механізму струшування стосовно розробленої конструкції молотка становив близько 350–400 грн за штуку. Отриманів роботі результати можуть бути використані на виробництві, при проектуванні технологічних процесів виготовлення деталей, що мають складний технологічний процес виготовлення.

Использование шеелитового концентрата для повышения износостойкости рабочей поверхности, восстановленной при электрошлаковой наплавке

Parts subject to intense abrasive wear have a short service life. In the manufacture or restoration of such parts by electroslag surfacing, strengthening of the deposited metal is required. The use of ready-made alloying powders in surfacing increases the cost of the finished part, which necessitates the search for cheaper materials for alloying the parts being welded. The study of the efficiency of alloying the deposited metal through the melted insert, as well as by direct introduction of alloying powders into the slag bath has been carried out. Mixtures based on enriched mineral scheelite concentrate and graphite are used as alloying powders

Research in the properties of hammers of the shaking mechanism of electrostatic precipitators manufactured by electroslag surfacing of the shock part

Research in the properties of hammers of the shaking mechanism of electrostatic precipitators manufactured by electroslag surfacing of the shock part

Application of chips of steel 5KhNM in electroslag surfacing of dies in current-conducting mold

Application of chips of steel 5KhNM in electroslag surfacing of dies in current-conducting mold

Применение стружки из стали 5ХНМ при электрошлаковой наплавке штампов в токоподводящем кристаллизаторе

Применение стружки из стали 5ХНМ при электрошлаковой наплавке штампов в токоподводящем кристаллизаторе

Electroslag surfacing of layers of different thickness in stationary current-supplying mould

Electroslag surfacing of layers of different thickness in stationary current-supplying mould

Электрошлаковая наплавка слоев разной толщины в стационарном токоподводящем кристаллизаторе

Электрошлаковая наплавка слоев разной толщины в стационарном токоподводящем кристаллизаторе

Effects of Vanadium on Microstructure and Wear Resistance of High Chromium Cast Iron Hardfacing Layer by Electroslag Surfacing

The 3.6C-20Cr-Fe-(0–2.32)V high chromium cast iron (HCCI) hardfacing layers were deposited on low alloy steel by electroslag surfacing. The microstructure of hardfacing layers were observed and the carbide types, size and area fraction were measured. In addition, the hardness and wear resistance were tested. Results show that the interface between hardfacing layer and low alloy steel is defect free. 3.6C-20Cr-Fe hardfacing layer contains primary carbides and eutectic. Increasing V wt % in the hardfacing layer, primary carbides are decreasing by increasing eutectic along with martensite formation. For 1.50 wt % of V, the microstructure contains a lot of eutectic and a little of martensite. For 2.32 wt % of V, primary austenite formed, the microstructure is primary austenite, eutectic and a little of martensite. In the V alloyed hardfacing layers, V has strong affinity with carbon than chromium, hence V can replace a part of Cr in M7C3 and (Cr4.4–4.7Fe2.1–2.3V0.2–0.5)C3 type carbides are formed. When the V is 2.32 wt %, (Cr0.23V0.77)C carbides are formed in the hardfacing layer. The hardness and wear resistance are improved by increasing V from 0 to 1.50 wt %. However, when the V is 2.32 wt %, the primary austenite has reduced the hardness and wear resistance of hardfacing layer.

Электрошлаковая наплавка высокохромистого чугуна на сталь 110Г13Л

Электрошлаковая наплавка высокохромистого чугуна на сталь 110Г13Л

Electroslag surfacing of high-chromium cast iron with 110G13l steel

Electroslag surfacing of high-chromium cast iron with 110G13l steel

Application of non-conducting consumable billets at electroslag surfacing in current-supplying mould

The Paton Welding Journal, 2018, №04. International Scientific-Technical and Production Journal «The Paton Welding Journal» «The Paton Welding Journal» has been published monthly since 2000 in English, ISSN 0957-798X. «The Paton Welding Journal» is a cover-to-cover English translation of the «Avtomaticheskaya Svarka» (Automatic Welding) journal. The «Avtomaticheskaya Svarka» journal has been published monthly since 1948 in Russian, ISSN 005-111X.

Использование нетоковедущих расходуемых заготовок при электрошлаковой наплавке в токоподводящем кристаллизаторе

Использование нетоковедущих расходуемых заготовок при электрошлаковой наплавке в токоподводящем кристаллизаторе