Arc Voltage Research Articles

Multi-Layers Composite Plasma Coatings Based on Oxide Ceramics and M-Croll

The paper considers the influence of the parameters of the plasma spraying process on the technological characteristics of multilayer coatings based on nickel-chromium, nickel-chromium-aluminum-yttrium materials, oxide ceramics, intended for operation at high temperature and additional dynamic loads. The design of plasma coatings during their application (with subsequent high-energy processing) under such conditions requires a comprehensive solution – both the use of high-quality powder ingredients and the optimization of technological parameters. The plasma process of applying powder materials has been improved to obtain the maximum values of their utilization factors. The technological characteristics that affect the properties of plasma coatings are optimized, namely: the flow rates of the plasma-forming and materials-transporting gases, the flow rate of supplied powder materials, the current and voltage of the electric arc of the plasma torch, the distance from the plasma torch nozzle exit to the substrate. The paper presents the results of studies of the structure of coatings, performed using scanning electron microscopy. Their analysis has made it possible to form general regularities obtained by the action of radiation of compression plasma flows on coatings formed by air plasma. The considered structures are created using the processes of melting, compaction and high-speed cooling of plasma coatings. The main optimization indicators are the maximum local compaction and spillage of the obtained compositions with the absence of defects and destruction from the impact of compression plasma flows. The main effect during the action of radiation of a compression plasma flow on previously formed coatings is thermal. It contributes heating of the near-surface layer. When the coating is exposed to radiation of compression plasma flows, a remelted layer of oxides with a thickness of about 12–15 µm is created, smoothing the relief of the formed surface and creating a network of cracks on the surface, diverging into the depth of the coating. The liquid-phase processes occurring in the molten phase of the near-surface layers after exposure to compression plasma radiation change the structure of the layers and contribute to the modification of their mechanical properties. By smoothing the surface, increasing the density of the surface crystallized layer and minimizing macro-defects – pores or macrocracks – the mechanical characteristics of the coatings increase.

Cooperation of an Electric Arc Device with a Power Supply System Equipped with a Superconducting Element

This paper analyses the validity of using superconductors in the power supply system of arc devices. Two cases were analysed: when an additional superconducting element was included in the conventional power supply system and when the total power supply system was made of a superconductor. The analysis was carried out by simulating the cooperation of the arc receiver with its simplified power supply system in Matlab Simulink software. The characteristics of the changes of the arc current, its conductance and voltage as a function of the arc length changes for selected superconductor parameters, i.e., different values of the critical current and different values of the resistance in the resistive state, are given. The time courses of these quantities as well as the courses of resistance changes in the superconductor at randomly varying arc lengths are presented. The analysis showed that by selecting the critical current and resistance in the resistive state of the superconductor, arc parameters such as arc current drawn and arc conductance can be influenced. By making the entire power system from a superconductor, the arc current can be increased by 1.8% for a 1 cm arc and by 1% for a 1 cm arc. The ability of the superconductor to lose its superconducting state and return to that state can be used to limit the value of the current drawn by the arc over certain ranges of arc length. The range of these lengths can be controlled by selecting the value of the critical current of the superconductor. By selecting the resistance of the superconductor in the resistive state, the value of the limited current can be influenced. In the case studied, for a 1 cm arc length, an arc current 45% lower was obtained when the superconductor was in the resistive state.

A novel reverse-polarity plasma torch with extended hot-wall nozzle for atmospheric plasma spraying of dense yttria-stabilized zirconia coatings

Due to the high heating temperature and low cost, atmospheric plasma spraying (APS) has been widely used in the preparation of ceramic coatings, but its coatings are normally formed by the stacked splats from fully or partially melted feedstock particles, which inevitably leads to some pores, unbonded interfaces or cracks. Thus, in this paper, a novel atmospheric plasma spraying technique using a reverse-polarity plasma torch (RPT) with extended hot-wall nozzle was proposed to fully melt and accelerate feedstock particles for the preparation of dense YSZ ceramic coatings. Firstly, the RPT spray system was designed in detail, and its main electro-thermal characteristics were experimentally studied. The results showed that the RPT exhibited higher arc voltage, thermal efficiency and lower arc voltage fluctuation than that of traditional rod-cathode/normal-polarity plasma torches (NPT) at the similar output power. Secondly, a numerical simulate was carried out to reveal the effect of the extended hot-wall nozzle on the temperature and velocity distributions of the plasma jet. The results showed that the extended hot-wall nozzle remarkably extended the high-temperature and high-velocity region of the plasma jet from the RPT exit to the downstream. Finally, the dense and uniform YSZ coatings with a porosity of about 5.3% were successfully prepared by the RPT with extended hot-wall nozzle. The results showed that the YSZ coating exhibited denser microstructure and fewer defects than that of the coating prepared by traditional APS process. Meanwhile, the hardness and Young's modulus of the YSZ coating were 11.9 ± 1.4 GPa and 197.9 ± 29.4 GPa, respectively, which were relatively higher than that of the coating prepared by traditional APS process, and were very close to that of the coating prepared by very low-pressure plasma spraying (VLPPS) process.

Effect of MIG Welding Parameters on the Mechanical Properties of AISI 304 Austenitic Stainless Steels

The present research investigates joints welding of 304L austenitic stainless steel using metal inert gas (MIG) welding method. The research explores the effect of process parameters (arc voltage, wire feed rate, and electrode wire diameter) on the mechanical properties of stainless steel. The above variables are varied respectively with 18.5, 19, 19.5 V, 116, 127, 137 mm/s, and 0.8, 1, 1.2 mm, with E308L as a filler electrode. The design matrix of the experiments was determined using the design of experiment (DOE) program Minitab 17 based on the levels of input elements used. The Taguchi orthogonal matrix methodology (Taguchi) technique was used to develop some empirical analysis for the maximum tensile strength and proper surface hardness as a function of the welding parameters mentioned above. The ( ) analysis was used to statistically verify the model's adequacy. The results show that the wire feed rate had the greatest effect on the tensile strength of the welded joints when choosing the medium level of arc voltage (19 V), while the arc voltage had a substantial influence on the micro-hardness of all welded joints. The weld-joint zone is given a higher micro-hardness value compared to the base metal zone.

Effect of arc voltage on process stability of bypass-coupling twin-wire indirect arc welding

With the development of bypass-coupling technique, the process window of twin-wire indirect arc welding has been effectively broadened, but the process stability is required to be further improved. In this paper, the influence of arc voltage on the stability of welding process was investigated through process experiments. It was found that the direct arc and indirect arc were alternately ignited. Under the condition of the output voltage at 32 V, the ratio of the indirect arc current to overall welding current was the largest. The weld was well formed with the output voltage above 32 V. Considering both the deposition efficiency and process stability, the desirable output voltage was 32 V.

Numerical simulation of external magnetic field effect on arc plasma after molten metal bridge breaking under different electrode opening velocities

In this study, a three-dimensional electromagnetic thermal fluid simulation program was developed to simulate arc movement numerically while considering metal vapor generated from a molten metal bridge along with an electrode opening under external magnetic field application. The change in the physical properties of the arc and the increment rate of the arc voltage per unit length under different electrode opening velocities were analyzed by applying an external magnetic field with different intensities. It was found that the current path of the arc became dispersed when the electrode opening velocity was high because the metal vapor generated from the molten metal bridge remained dominant and highly concentrated. Before the completion of the electrode opening process, the difference in the increment rate of the arc voltage per unit length at different electrode opening velocities became more significant when an external magnetic field was applied. This was because under high and low electrode opening velocities, the cross-sectional area of the arc became narrow and broad, respectively.

Electric Arc Length Control of Circular Seam in Welding Robot Based on Arc Voltage Sensing

Arc length control plays an important role in improving welding quality, especially for tube-to-tubesheet welding with numerous and dense circular seams. The difficulty of arc length control lies not only in acquisition and processing of arc voltage signal, but also in designing reasonable tracking algorithm and control method. This paper proposes an arc voltage tracking system with a self-developed arc voltage module for orbiting robotic welding. A real-time arc voltage tracking algorithm based on direct current (DC) pulse square-wave is proposed, and a two-dimension and three-section fuzzy controller are also presented. The experimental results show that the maximum peak voltage (PV) decreases from 13.92 V (circular seam A) to 13.44 V (circular seam B). The surface morphology of circular seam B with arc voltage tracking is obviously superior than that of circular seam A without arc voltage tracking. The arc voltage tracking method proposed in this manuscript has an active influence on welding quality.

Arc voltage measurements for height control in pulsed arc additive manufacturing

Pulsed-gas tungsten arc additive manufacturing (P-GTA AM) is highly suitable for producing high-performance and large-size components. However, research work concerning monitoring and control to increase process automation and steadiness is extremely inadequate. Aiming at a stable deposition in P-GTA AM, an arc voltage (AV) measuring and feedback control strategy is proposed. The novelty is that noises in pulsed AV are removed via an empirical mode decomposition denoising method and the peak AV is determined as the optimal feedback signal to characterize height variations by conducting static and dynamic tests. A fuzzy logic PID controller is designed to control the peak AV by regulating the amount of filler wire. Thin walls are manufactured to check the controller’s robustness, and the application of the control system through feedback from AV measurements can excellently ensure stable deposition height in P-GTA AM with a maximum AV deviation of 0.4 V.

Distribution Network Voltage Arc Suppression Method Based on Flexible Regulation of Neutral Point Potential of the New Grounding Transformer

Aiming at the problems that the existing arc suppression cabinet technology cannot adjust the zero sequence voltage flexibly and the control and hardware implementation of active arc suppression equipment based on power electronics are difficult, a new method of voltage arc suppression in the distribution network based on the flexible regulation of the neutral point potential of the new grounding transformer is proposed. From the perspective of the sequence component, the variation law of the neutral point voltage before and after the closing of the tapped grounding branch of the new grounding transformer is analyzed. By selecting the appropriate initial tap position of the tap-to-ground switch, the fault phase voltage is flexibly controlled so that the fault phase voltage is reduced to below the reignition voltage to quickly solve the influence of the single-phase grounding fault, and the risk of non-fault phase insulation breakdown is reduced to ensure the stable operation of the distribution network. According to the ratio of the fault phase current to the zero sequence voltage before and after the gear inputs, whether the arc suppression of the single-phase grounding fault is completed is judged. Compared with power electronic products, the new grounding transformer has the advantages of high reliability, long service life, and low cost and has strong economy and applicability in engineering. The single-phase grounding fault model of the 10kV distribution network is built in the PSCAD/EMTDC simulation environment, and the new method of the distribution network voltage arc suppression based on the flexible regulation of neutral point potential of the new grounding transformer is verified. The simulation results show that the proposed method can effectively reduce the fault phase voltage to achieve the reliable arc suppression of the single-phase grounding fault.

Experimental Study on the Extinction Characteristics of Secondary Arc Under Different Secondary Arc Currents Near Outdoor Insulator

On the transmission lines, the secondary arc is the arc that remains at the fault point after the short-circuit current is interrupted, which may pose a threat to the stable operation of the power system. In this article, the extinction characteristics of secondary arc near an outdoor insulator under different secondary arc currents are studied experimentally. The secondary arc has different extinction characteristics under different secondary arc currents of 10, 30, and 50 A. The arcing time, length, morphology, diameter, and breakdown voltage of secondary arc are discussed. Experimental results show that, with the increase in the secondary arc current, the arcing time also increases. The development of the secondary arc has stage characteristics. The length of the secondary arc increases steadily in the first stage and fluctuates greatly in the second stage. In addition, during the single discharge in the second stage, the morphology of the secondary arc will change significantly. The breakdown voltage of the upper electrode in the negative polarity is higher than that in the positive polarity, and it is found that this polarity effect is related to the motion of the secondary arc in space. The research results could provide some reference for investigating the physical characteristics and suppression measures of secondary arc.

Muzzle Arc Flow Field Simulation of a Small Caliber Launcher

Muzzle arc is a general phenomenon when the armature leaves the muzzle, and it is also a reason for the complexity of intermediate ballistic of electromagnetic launchers. In this article, a 3-D model has been developed to investigate muzzle arc flow field in a smaller caliber launcher. The coupled interaction of electromagnetic, flow, and thermal fields is realized by the magnetohydrodynamic (MHD) theory in conjunction with a renormalization group (RNG) <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> - <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\varepsilon $ </tex-math></inline-formula> turbulence model. The arc boundary conditions, arc root radius, and time-dependent current density are reasonably set on the basis of the experimental data and physical process. Simulation results reveal the relationship between muzzle arc and muzzle voltage. The rising edge of muzzle voltage corresponds to the arc expansion stage. The falling edge corresponds to the muzzle breakdown stage. And the turning point from rising edge to falling edge is the moment of muzzle breakdown. The flat section corresponds to the arc extinguishing stage. The muzzle blowback is the consequence of the arc expansion which produces a compression wave moving toward the breech. The velocity of blowback flow decreases from 670 to 270 m/s during the arc expansion stage. Then, it increases to about 350 m/s and tends to be stable due to the muzzle breakdown.

Influence of cusp external magnetic field on deposition rate of two-electrode TIG welding

Experiments have been conducted to investigate the influence of the cusp external magnetic field (EMF) on deposition rate of two-electrode tungsten insert gas (T-TIG) welding. T-TIG arc parameters such as arc shape, arc voltage, arc pressure, and arc plasma information were acquired respectively. Results showed that compared to TIG a higher welding current could be allowed for T-TIG due to its low arc pressure characteristic. Under the effect of the cusp EMF, the arc shape was compressed along the x-axis of T-TIG, while elongated along the y-axis of T-TIG. Besides, the peak arc pressure of T-TIG was not significantly increased by the cusp EMF. Moreover, with the action of the cusp EMF, the maximum values of the electron temperature (Te) and electron density (Ne) of T-TIG were not significantly increased, but along the y-axis, the increments of the two parameters were gradually increased and their distributions were widened. Therefore, more arc energy was allocated on the y-axis of T-TIG by the cusp EMF, which could improve the preheating and the melting of the filler wire along the y-axis, so the deposition rate of T-TIG could be increased by 17.6% under the effect of the cusp EMF.

Modeling and Optimizing the Penetration in the Submerged Arc Welding Process in the Presence of ZrO2 Nanoparticles

Abstract Penetration is one of the most vital parameters because of its influences on weld strength and weld quality. Choosing the input parameters in submerged arc welding (SAW) has significant effects on input heat into the weld pool, which affects the quality of weldment. The amazing advancement of nanotechnology in various industrial areas persuaded researchers to use nanoparticles in new research. Zirconium dioxide (ZrO2) nanoparticles were selected in order to identify their effects in the weld pool in combination with other welding input parameters. The five-level, five-parameter central composite rotatable design, response surface methodology, the slime mold algorithm, and Harris hawks optimization were utilized to design and develop the research and finally to predict and optimize the weld penetration affected by the arc voltage, welding current, nozzle-to-plate distance, welding speed, and the thickness of ZrO2 nanoparticles coated on ST-37 steel. The main and interaction effects of input parameters on weld penetration were drawn. The results demonstrated that weld penetration decreased initially by increasing the thickness of ZrO2 nanoparticles up to 0.25 mm, which was due to reversing Marangoni convection mode. Furthermore, weld penetration increased with increase in ZrO2 nanoparticles above thicknesses of 0.75 mm. The reason for increase in weld penetration was because of the fact the ZrO2 nanoparticles have low thermal conductivity, which leads to less heat transfer. The results confirmed that the accuracy of model obtained by slime mold algorithm was 5.2 % more than response surface methodology.

Dynamic molten pool behavior of pulsed gas tungsten arc welding with filler wire in horizontal position and its characterization based on arc voltage

To explore the dynamic behavior of molten pool and to find the electric characteristic signals reflecting the weld penetration states and degree for the fixed-point wire-filled pulsed gas tungsten arc welding (GTAW-P) of thin pipes in 2G position, molten pool images from different directions and arc voltage were sensed. During a peak current period, critical penetration occurred, with the molten pool behavior that the topside molten pool height collapsed sharply and was approximately 0.5 mm, and then rose to approximately 1.5 mm during the next base current period. With the increase in backside molten pool width, the oscillation amplitude and frequency of topside molten pool during the base current period increased and decreased, respectively. The oscillation amplitude reached the maximum when over penetration occurred. Such molten pool behaviors could be extracted from the arc voltage signals. The change in average peak voltage (ΔU⁎) could reflect the occurrence of critical penetration. The average base voltage (Ub¯) and the fluctuation of base voltage (ΔUb) increased linearly with the increase in backside molten pool width, which are reliable characteristic signals for the weld penetration degree. The effects of wire filling and base current on the dynamic molten pool behavior and characteristic signals were investigated. Experimental results showed when the base current is 10 A ̶15 A, Ub¯ and ΔUb can effectively characterize the weld penetration degree.

Multiscale feature extraction and its application in the weld seam quality prediction for plasma arc welding

As a complex thermo-physical process, the plasma arc welding (PAW) is easy to be unstable due to external interferences. Weld quality monitoring is important for intelligent robot PAW welding. Due to the different instability mechanisms, it is difficult to obtain high adaptivity and accuracy with features extracted in a single time window. In this paper, a novel feature extraction method based on sliding multiscale windows is proposed to improve model accuracy and calculation speed. A group of windows with different time widths are established to extract multiscale information. Windows slide throughout welding process and are synchronized on the timeline for feature correlation. The welding current and arc voltage are processed to extract features inside windows, including signal denoising by discrete wavelet transform (DWT) and dimension reduction by primary components analysis (PCA). Based on the feature vectors extracted from multiscale-windows, support vector machine (SVM) with radial basis function (RBF) kernel is used. The best window width is determined automatically by model training. The proposed method is used to predict weld quality for PAW in the field of shipbuilding. The results show that the model with multiscale feature extraction is helpful to improve prediction precision and recall ratio.

ОСОБЕННОСТИ МЕХАНИЗИРОВАННОЙ НАПЛАВКИ В СРЕДЕ УГЛЕКИСЛОГО ГАЗА

This article discusses the issues of mechanized surfacing in a carbon dioxide environment. A method for calculating the parameters for mechanized surfacing in a carbon dioxide environment is presented: tables are presented for selecting parameters and formulas for calculating, namely: average values of allowances for turning shafts, average values of allowances for grinding shafts, selection of the electrode wire diameter, limits for changing the parameters of the surfacing mode, welding current strength and corresponding arc voltage, electrode reach, carbon dioxide consumption, internal diameter of the wire feed spiral depending on the diameter of the electrode wire.

Optimization of the mechanism welding mode in a shielding gases environment of shell structures in the position “on weight”

Due to their simplified spatial shape, shell cylindrical designs have acceptable manufacturability. The latter makes it possible to use a variety of fusion welding methods in their manufacture, including the option of mechanized welding in protective gas environments. Such a technological process is considered to be sufficiently developed in terms of theory and application, as evidenced by specialized equipment for it and numerous recommendations for the selection of installation and running welding parameters. Analysis of such material demonstrates that the basic technology is welding in the lower position with a seam root lining or with the use of a suitable technological arrangement for rotating large structures to provide such conditions. Much more difficult to meet the quality requirements for a welded joint are repair and welding works of non-rotating structures with a one-sided approach to the welding zone and the absence of a seam root lining. In this case, welding equipment with electric or electric-mechanical control of the process of dropwise transfer of metal into the bath is used, regardless of the spatial position of the seam. However, in cases of single production or repair welding, classical welding sources are still widely used, in which the regulatory requirements for the weld are provided by its appropriate external characteristics, the effect of self-regulation of the arc and dynamic characteristics. Here, the variant of droplet transfer with a short circuit of the droplet to the bath is typical, with the characteristic instability of energy accumulation / return of the source choke at the stages of the arc and droplet and the corresponding behavior of the arc in different spatial positions. Since the parameters of the mode are interdependent and, thus, welding itself represents a poorly organized system that has a variety of physical parameters that cause different in nature, but tightly interconnected processes in the zone of weld formation. The best tool for assessing the condition and regulation of such a system today is planning an experiment with independent controlled (setting) parameters of the welding mode and quality feedback – the optimized amount of weld penetration. On the basis of the processing of the array of recommended data regarding the selection of the value of the setting parameters of the welding process by the procedure of constructing symmetric histograms and the distribution polygon and calculating the analytical model of the description of the distribution density for each setting parameter of the process, their average values are set with a probability of 0.9. The latter were used to calculate the actual values of the following parameters for welding a given material thickness – electrode wire diameter 1.6 mm, welding current 190 A, voltage 25±1 V, welding speed – 26–42 m/h, wire feed speed 21–29 m/h, electrode discharge wire 16 mm. On the basis of the specified reference base of parameter values, a planned experiment was set up and implemented to find the optimum on a matrix of a composite symmetrical three-level plan, as variable factors are set – process voltage, welding wire feed speed and welding speed; the height of penetration of the assembled parts is set by the response. The region of the optimum and the influence of the setting parameters of the mode on it, as well as the analysis of its response surfaces and cross sections of such surfaces demonstrate that the setting parameter – the source voltage should practically be constant at the level of 24 V and does not have a significant adjustment ability for the correction of the welding mode. The setting kinematic parameters of the mode are the wire feed speed and the welding speed, respectively 23 and 27 m/h, at the given arc voltage, they provide welding in one pass. In terms of the depth of the ability to adjust the quality of the seam formation, the welding speed prevails, since, all other things being equal, the wire feed speed is strictly correlated with the speed of its melting at a given diameter and electrode distance. The latter determine the actual value of the current, the value of which is limited by the source voltage, which is strictly specified and constant for the given process under study.

Підвищення технічного ресурсу і довговічності робочих органів ґрунтообробних сільськогосподарських машин

The working bodies of tillage agricultural machines (ploughshare, plow shelf, cultivator paw, harrow disc) work in conditions of abrasive operation, shock loads and the impact of external aggressive environment. Their repair is to restore the original size of parts and wear resistance of functional work surfaces. During the operation of tillage machines and units, the working surfaces are subjected to uneven wear, which reduces the life of parts and increases the cost of their replacement and restoration. The working bodies of tillage agricultural machines (ploughshare, plow shelf, cultivator paw, harrow disc) work in conditions of abrasive operation, shock loads and the impact of external aggressive environment. Their repair is to restore the original size of parts and wear resistance of functional work surfaces. During the operation of tillage machines and units, the working surfaces are subjected to uneven wear, which reduces the life of parts and increases the cost of their replacement and restoration. The current level of operation of agricultural machinery is characterized by increased speeds and high productivity, which, in turn, leads to increased wear of parts. accordingly, the reliability of the recovered machines will depend on the wear resistance and fatigue strength of the recovered parts. The leading place in the repair of machines is occupied by welding and surfacing processes, which account for about 80% of all restorative parts. Surfacing makes it possible to obtain layers of any thickness and chemical composition on the working surfaces of parts; apply a welded layer with different properties, ie high hardness and wear resistance. In this work we use point (point) hardening, which consists in micro-dripping of the hard alloy into the surface structure of parts that undergo intense abrasive wear. The geometry of the hardening point is a spherical sector, which facilitates the rapid removal of heat from the surfacing bath in the base metal and the environment, so the hardening points harden at high speed and in a short time. At point strengthening of details one of the main conditions providing stable quality of process - coordination of welding current and arc voltage. The sawtooth profile of the ploughshare blade (cultivator paws) is maintained throughout its service life. providing effective cutting even with the blades worked.

Submerged arc welding process parameter prediction using predictive modeling techniques

Models are required by automation systems in order to forecast the influence of different industrial process factors in real time. Welding is a metal joining procedure that is utilised extensively in the fabrication industry. Welding speed, welding current, Arc voltage and Electrode stick out were taken as an input parameters and the weld quality was taken as an output parameter. Fuzzy logic is used to simulate the Submerged Arc Welding (SAW) process and forecast weld quality in this article. Using Taguchi’s approach and regression analysis, a fuzzy logic model was constructed using training data gathered via experimentation. Confirmatory tests are carried out to determine the efficacy of this strategy. This research has substantial implications for material savings and quality improvement also it is a step towards the construction of self-driving factories.

Градиент напряжения дуги как многофакторная базовая электрическая характеристика дуговой сталеплавильной печи

The structure of the complex process of heating with an electric arc in an arc steelmaking furnace (ASF) due to radiation and convection depends primarily on the length of the arc. Identification of arc length required in process of melting control in ASF is impossible without knowledge of arc voltage gradient values. The arc voltage gradient is highly dependent on the temperature of the furnace and thereby on the heat exchange conditions of the arc in the melting space of the furnace during melting. Using the example of ASF, an engineering technique for determining the arc voltage gradient as a multifactorial basic electrical characteristic is proposed. Using the methods of the electric arc heat exchange model allows performing a basic two-factor version of the analytical calculation of the average voltage gradient of the arc column as a function of two parameters - the reactance of the furnace and the secondary voltage of the furnace transformer. Correction of the basic function is shown taking into account the value of the resistance of the equivalent ASF circuit and the electrode thermal mode index. The proposed method allows, already at the stage of development of the detailed design specification, to calculate analytically the most important energy physical characteristics of the ASF and, as a result, to choose a rational electrical mode of the ASF in order to improve energy and dynamic smelting indicators.