CC BY
21TECHNICAL SCIENCES
CHOICE OF PLASMA-GENERATING ENVIRONMENTS TO IMPROVE THE QUALITY OF
PLASMA CUTTING IN SHIPBUILDING
Korzhyk V.,
Shandong (Yantai) Sino-Japan Industrial Technology Research Institute (Yantai) I
ndustrial Technology Research Institute Shandong, China
E.O. Paton Electric Welding Institute, National Academy of Sciences of Ukraine of Ukraine
Kyiv, Ukraine Wang H., Sun Yu.,
Shandong (Yantai) Sino-Japan Industrial Technology Research Institute (Yantai)
Industrial Technology Research Institute Shandong, China.
Khaskin V., Strohonov D., Ganushchak O., Peleshenko S., Aloshyn A.
E.O. Paton Electric Welding Institute, National Academy of Sciences of Ukraine of Ukraine
Kyiv, Ukraine DOI: 10.5281/zenodo.7618436
ABSTRACT
The work is devoted to the analysis of the choice of plasma-forming media for plasma torches used in complexes for plasma cutting of steel parts for shipbuilding problems. During plasma cutting, a heat-affected zone is formed with areas of structural changes and a cast layer on the cut surface. The length of the cast section is determined by the interaction of the plasma jet with the molten metal and its oxides during the cutting process. Minimizing the depth of the cast area reduces the roughness of the cut surface and the degree of unfavorable metallurgical changes in the properties of the parent metal at the cut edges. The effect of various plasma-forming gases on the quality of plasma cutting is analyzed: air, nitrogen, 80% nitrogen + 20% hydrogen, 50% argon + 50% oxygen, oxygen. It has been established that the highest saturation of the cast layer with nitrogen (up to 0.2-0.5%) is observed when air is used. The negative effect of nitrogen saturation of the cut edges is manifested in a significant increase in their hardness, as well as in the formation of pores in the welds obtained during subsequent welding of the cut parts. In the presence of hydrogen, the absorption of nitrogen by steel slows down. The rate of nitrogen desorption increases with an increase in the concentration of hydrogen in the gaseous medium to the power of 3/2. The binding of nitrogen in the plasma jet is positively affected by hydrocarbons. In addition, plasma-forming mixtures of air with hydrocarbons increase the energy efficiency of plasma cutting.
Keywords: plasma cutting, steels, HAZ, cast layer, defects, nitrogen saturation, plasma-forming environment, influence on subsequent welding.
Quality indicators of parts cut by any means of thermal cutting are the values of linear and angular dimensions that characterize their dimensions and shape, as well as strength and other properties that determine the performance of the part and the metal from which it is made. Deviations from the nominal values of dimensions lead to additional labor costs during assembly and welding of the structure in the form of fitting work and an additional volume of deposited metal, and changes in the properties of the metal in the heat-affected zone, for example, during plasma cutting, can cause pore formation during submerged arc welding, cracking and other defects in the weld, as well as a decrease in the strength of parts in the presence of free non-weld edges. Deviation from the nominal values of quality indicators arises due to the occurrence of errors that can be divided into three main groups: errors of the program itself and / or its carrier; machine error; deviations that occur during the execution of the technological process.
As practice shows, the largest deviations in absolute value occur during the execution of the technological process. So, due to improper selection of the power of the cutting equipment, non-cuts can occur, at too low a cutting speed, the gap between the upper edges is less than the gap between the lower ones (taper), and at too high a speed, vice versa (reverse taper). To improve the quality of plasma thermal cutting, one of the important factors is the correct choice of the plasma medium. This factor affects both the productivity and quality of the cut, as well as its economy. Therefore, the correct choice of a plasma-forming medium and the selection of components added to it is an urgent task in the development of plasma cutting technology for metals.
The purpose of the work is to substantiate the correctness of the selection of plasma-forming media for cutting plasma torches, which are used in complexes for plasma cutting of steel parts for shipbuilding tasks, based on a review of literary sources.
The productivity of the thermal cutting process is
predetermined by the cutting speed, and the efficiency is determined by the cost of oxygen, combustible gases for the preheating flame (acetylene, propane-butane, gasoline, kerosene, etc.), electricity, plasma gases, electrodes and other technological materials and spare parts. The given parameters of the technological process of thermal cutting (accuracy, productivity and economy) also depend on the properties and thickness of the metal being cut. These interrelations find their most generalized expression in cutting modes, the optimal values of which are determined as a result of research on cutting metal of each grade and thickness. The plasma-forming environment has a significant influence on the modes, technology and quality of plasma cutting.
The system for assessing cutting accuracy [1] is based on the differentiation of requirements for the limiting values of 4 main indicators: size tolerance, cut perpendicularity, surface roughness, and depth of the heat-affected zone. The first two indicators characterize the accuracy of cutting, and the rest - the cleanliness of the cut surface, structural and chemical changes in the metal.
For each indicator, 3 standardized accuracy and quality classes are established for parts and workpieces of the same size, depending on their purpose and conditions of use:
- the first - meets the highest requirements for accuracy indicators;
- the second - the requirements that are realistically achievable in production conditions, subject to generally accepted measures to maintain cutting accuracy;
- the third - the minimum requirements for the limiting values of indicators.
When determining the quality of cutting, the width of the cut, the amount of burr (nodules on the lower edge of the metal), the lag of the cut line in thickness, and the radius of fusion of the upper edge are also important. Rounding of the edge angle due to flashing is allowed at a radius of 1 mm.
The method and modes of cutting parts must be assigned such that provide a minimum heat input into the cut part. In this regard, in all cases, where possible, plasma cutting should be used, which, at higher cutting speeds (by a factor of 2-5), has a heating energy input that is approximately 3 times less than oxygen cutting. Due to the high technical and economic characteristics, the plasma cutting process has become widespread in various industries. Ar, N2 and their mixtures, gases based on hydrogen (Ar + H2, etc.) or oxygen (compressed air, N2 + O2, etc.) are used as plasma-forming gases. The cutting process in plasma-forming mixtures containing hydrogen is carried out by melting the metal along the cut line and proceeds through the use of electrical energy supplied from the outside to the arc. The use of plasma-forming mixtures, which include oxygen, makes it possible to use both electrical and chemical energy when cutting. Cutting in this case is partly the process of melting and partly the process of burning out the metal from the cut cavity [2]. The cutting speed depends on the oxygen content in the nitrogen-oxygen mixture, reaching a maximum at 65...70% oxygen [3],
which is explained by the so-called nitroxide effect [4]. Its essence lies in the fact that nitric oxide NO is a more active oxidizing agent than pure oxygen. The maximum cutting speed in N2 + (65...70)% O2 mixture is 35...40% higher than in air plasma, however, the constraining factor in the use of such a mixture is the need for two gas sources, intensive nozzle wear and electrode consumption [3]. Therefore, when cutting steels, compressed air has received the greatest use as a plasma-forming medium, as the most common and cost-effective gas [5, 6].
The cutting factors of the plasma arc are the active anode spot, which transfers up to 60...80% of heat to the metal, the arc column and torch, which transfer 20...40% of heat by radiation and convective transfer [4]. The behavior of the arc during plasma-arc cutting is considered in [7]. The intensity of heat transfer from various cutting factors determines the quality and width of the cut cavity melted along the height.
The non-uniformity of the cut width along the sheet thickness causes non-parallelism of the cut surfaces and their non-perpendicularity to the sheet surface [8]. The non-parallelism is determined by the diameter of the anode spot, the speed of its movement, the area and frequency of cut shunting and depends on the cutting speed, arc current and voltage, gas flow rate, diameter and length of the nozzle channel, its height above the metal surface, metal composition and the nature of the plasma-forming medium [4]. To eliminate the qualitative disadvantages of plasma-arc cutting, it is recommended to reduce the cut width to the maximum, using plasma torches with nozzles of the minimum diameter, and rigid stabilization of the cutting arc at the highest energy density [4]. It can be assumed that the addition of water to the plasma-forming air, contributing to arc compression, will also improve the quality of cutting.
The use of water in plasma cutting began in the sixties of the last century to solve the problem of dust, noise, light and gas absorption. The papers [9, 10] present the results of a study of plasma cutting with an additional water curtain around the plasma torch, with the sample touching the water surface or with a gap between them of 15 mm and with the sample immersed in water. At the same time, it is noted that the minimum values of cut non-perpendicularity were reached when cutting on the water surface, and cutting with the sheet immersed in water gave a greater roughness.
In [11], plasma cutting of sheet metal on the water surface was studied and it was recommended that metal thicknesses up to 12 mm be cut using oxygen, and when welding thicknesses of 4-6 mm, preliminary welding in CO2 is required to prevent the formation of pores.
In Europe, plasma cutting under water is widely used [12, 13]. For example, in the German shipbuilding industry, plasma cutting under a water layer is most widely used, providing a fourfold increase in cutting speed compared to oxy-fuel cutting, improved cutting quality, minimal slag, slight deformation, less noise and dust [12]. A similar technology is used at the «Damen Shipyards "Okean"» shipyard. Nitrogen is used as the plasma gas.
When cutting metal immersed in water even to a
depth of 20...30 mm, it is very difficult to initiate an arc. Cutting requires equipment that maintains a pilot arc in argon, which causes excitation of the main arc. This turns on the working gas and turns off the argon. The disadvantage of this cutting method is a decrease in cutting performance or (with an increase in arc power) an increased consumption of electricity [14]. The implementation of the method also requires large capital expenditures.
One of the options for using water in plasma cutting is water-electric cutting, in which only water is used, gas is not supplied to the plasma torch [14]. At the same time, it is possible to obtain high stability of the plasma arc and high cutting quality. The cut edges have a slight bevel and metallic sheen, however, arc excitation and the beginning of the process are problematic, which makes water-electric cutting insufficiently technological and reliable [14]. Therefore, this method of cutting has not found wide application.
More promising is plasma cutting with a small amount of water fed into the plasma. Nitrogen is most often used as a plasma-forming gas [14]. Water must not be supplied together with gas, as its entry into the cathode space will destroy the electrode and nozzle. Therefore, water is supplied separately to the nozzle channel, where it evaporates intensively. Depending on the temperature, the evaporation of 1 cm3 of water produces about 1720 cm3 of steam. Inside the channel, water is supplied with a swirl.
It is known from the literature data that the addition of water to the plasma-forming gas improves the quality of cutting and the resistance of the weld metal against pores [14], but the effect is manifested at certain water flow rates. In [14, 15], the total water flow in the plasma torch is indicated, which does not allow determining the fraction of steam in the plasma-forming medium. It is not known from the published works which parts of the water enter the nozzle channel and into the plasma.
It is known [2, 16] that the energy characteristics of a plasma arc depend on the composition of the plasma-forming medium, since this changes the electric field strength of the arc and the specific heat content of the plasma. An analysis of various gases shows that hydrogen provides the best conditions for converting electrical energy into thermal energy. Therefore, the addition of water to the plasma can significantly affect the quality of the cut during the formation of hydrogen. For example, it was experimentally established in [17] that the addition of methane to the plasma-forming air radically changes the conditions of arc burning, which manifests itself in an increase in the voltage level on the arc and a change in the nature of the arc current distribution along the nozzle channel. The effect of the influence of methane is manifested even with small additives (up to 1%, vol).
There are no theoretical substantiations and regularities of the influence of water vapor additives on plasma-chemical processes and composition of the gas phase during cutting in the literature. Our first studies of air-plasma cutting showed a positive effect of water additions, but it is necessary to determine the limiting
values of water additions to plasma and evaluate its effect on plasma composition. Therefore, one of the tasks of the work was to model the composition of the gas phase when water is added to the plasma-forming air and to establish the patterns of its influence on the quality of the cut, as well as welded joints from steels of categories D32, D40. Hydrocarbon additives were also used for comparison.
At the shipyard «Damen Shipyards "Ocean"» plasma cutting is used under a layer of water [18]. The use of the NUMOREX machine made it possible to achieve the required accuracy in the manufacture of assemblies and sections and eliminate fitting work at the stage of the hull stack assembly. The operating experience of NUMOREX machines has shown a relatively low utilization of machine time (about 60%), which is due to the traditional technology of stacking sheets and removing finished parts from the cutting frame. Therefore, the TELEREX TXB-10200 machine with four cutting frames installed in water basins has now been put into operation, which made it possible not only to simultaneously cut symmetrical parts of the left and right sides, but also to mark and disassemble the parts, practically eliminating machine downtime. The disadvantage of NUMOREX and TELEREX TXB-10200 machines is their high cost. In addition, the application of underwater cutting requires special cutting tables with a water level control system. The water should be low in salt to increase the durability of the nozzles. Water treatment should be provided to avoid oxidation of cut edges and removal of products of plasma-chemical reactions occurring in water. When cutting under water, the operator cannot monitor the position of the plasma torch and the quality of the cut edges, it requires the use of special height stabilizers and an emergency shutdown system in case of accidental overturning of small parts. On current thermal cutting lines using moving cutting frames, the use of this cutting method is practically impossible.
The non-perpendicularity a of the edges can be several millimeters during air-plasma cutting. In this case, the cross-sectional area of the deposited metal increases by the value a S, where S is the thickness of the metal, and, accordingly, the volume of the deposited metal also increases (Fig. 1). An increase in the volume of deposited metal leads not only to additional costs of welding materials and a decrease in labor productivity, but also to a deterioration in the quality of the structure, since it requires an increase in the heat input of welding and leads to a significant increase in the volume of longitudinal shortening of the welded joint. The non-perpendicularity of the edges of the sheets to be welded also causes angular deformations. It leads to a groove welding pattern in which the angular deformation is mainly due to the contraction of the weld metal. It is known [19, 20] that the value of the leaf rotation angle P is determined by the equation
where AB is the shortening of the upper layer of
the bead in the transverse direction; S is the sheet thickness; a is the coefficient of linear thermal expansion; T* is the temperature of restoration of elastic properties by the metal; 0 is the cutting angle.
Obviously, when welding sheets with non-perpendicularity a and non-perpendicular angle ^ (tg ^ = | ), the angle of rotation is determined by the equation:
" (2)
ß = 2a-T--
The scheme of angular deformation is shown in Fig.1. Thus, the deterioration of the cutting quality increases local welding deformations, causing ribbing, mushrooming, houses, and general welding deformations, causing distortion of the shape and dimensions of the entire structure [20].
In addition, as a result of physicochemical processes that occur during the interaction of plasma and molten metal of the cut surface, it is possible to saturate the metal of the edges with gases. Depending on the composition of the plasma-forming medium, the amount of gases and the depth of their penetration can be different [2, 5, 16, 21]. Saturation of the metal of the cut edges with gases, primarily nitrogen, can lead to the formation of pores during welding.
In [22, 23], the influence of various plasma-forming media on pore formation in welds made along the edges after plasma cutting was studied. Butt welding was carried out by semi-automatic submerged arc welding OSC-45 with wire Sv-08A with a diameter of 2 mm on plates of steel 09G2 8 mm thick. The results are shown in table. 1.
a) b) I
Fig. 1. Schemes of angular deformation during sheet welding (a) and edge preparation by thermal cutting (b).
Table 1.
Plasma-forming environment Gas consumption, m3/hour Cutting speed, m/min X-ray control results
Air 4,5 2,5 A chain of pores along the entire length of the seam.
Oxygen 10,3 3,1 A chain of pores for % of the seam length.
Oxygen 4,5 0,8 Pore no.
Argon 5,0 0,8 A chain of fistulas along the entire length of the seam.
CO2 4,0 1,6 A chain of pores along the entire length of the seam.
In order to check the existence of a liquid film, a metallographic study of the edges after plasma cutting in various plasma-forming media, as well as after oxy-acetylene cutting, was carried out. It has been established [4] that a film of molten metal remains on the cut surface both during plasma and oxy-fuel cutting (Table 2).
Table 2.
Influence of the plasma-forming medium on the thickness of the film of molten metal of the cut edges [4].
Plasma-forming environment Film thickness, mm
Argon 0,12
Air 0,04
Oxygen Not detected
Based on the analysis of the obtained experimental results on cutting in various plasma-forming media, it was suggested that there is a mutual relationship between the occurrence of porosity, the presence of a molten film on the cut edge, and its gas saturation [23, 24].
The results of these tables 1 and 2 are in satisfactory agreement with each other. The greater the thickness of the molten metal film on the cut edge, the more pores in the welds. Liquid metal in the process of cutting is intensively saturated with gases from the plasma jet. However, when welding specimens cut by oxy-acetylene cutting, no pores were found in the weld, and the film thickness is commensurate with the film thickness from air-plasma cutting. Therefore, pore formation is affected not only by the presence of a film of molten metal on the cut edges, but also by its contact with gases
When changing some parameters of the cutting mode (gas consumption, cutting speed, nozzle diameter), the porosity of the welds changes.
In [12, 26], the absorption of nitrogen from plasma by remelted metal was studied. It turned out that in the metal remelted with the help of an arc plasma, the nitrogen content is anomalously high and not only exceeds the equilibrium state corresponding to the partial pressure of N2 in the gas phase, but also exceeds the standard nitrogen solubility in liquid metal. The level of nitrogen concentration in the metal during melting with a plasma torch of direct action exceeded 2.4 times,
The nitrogen content in steels was studied in [3136]. When nitriding mild steel with a carbon content of 0.12% for 30 hours at 680°C in ammonia, the nitrogen content in steel did not exceed 6.9%. Moreover, nitrogen was in the form of Fe4N nitride [32]. The nitrogen content in open-hearth carbon steel does not exceed 0.008-0.009% and is usually 0.005-0.006% [36]. The
in an excited state. This condition is satisfied only for the case of plasma cutting. In particular, for nitrogen, the steady-state level of concentration in the metal is 23 times higher than the standard solubility.
In [25], the influence of various technological processes of plasma cutting on pore formation was studied and it was found that the cut edges are saturated with nitrogen. The nitrogen content was determined in chips taken from the cut edge to a depth of 0.5 mm and is given in Table 3. The nitrogen content in the base metal was 0.013%.
and indirect - 3.2 times the standard solubility of nitrogen in steel.
In [27, 28], the gas saturation of the edges of parts cut by plasma cutting was studied by the spectral isotope method for determining gases in the surface layer of a metal using an optical quantum generator (OQG) [29]. The distribution of nitrogen content from the cut surface deep into the edge was determined with layer-by-layer removal of metal from the side of the cut. The melted spot on the surface of the sample at the moment of gas extraction from the metal had a diameter of 4 mm and a depth of 20 ^m. The results of the analysis are given in Table 4 [30].
Table 4.
same applies to steels produced in electric arc furnaces. Quiet carbon converter steel typically contains 0.00250.004% nitrogen.
In [35], the intensive saturation of the edges of low-carbon steel with oxygen is also noted, and in [33], as the most effective means of reducing the nitrogen concentration in the cut edges, oxygen-plasma cutting
Table 3.
The content of nitrogen in the edges of a plasma cut depending on the plasma-forming medium and its __effect on the quality of welds.__
N2 content in the edge, % The results of the external examination of the seam Results of X-ray inspection of welds
Air 0,322 Fistulas with a diameter of 1 to 5 mm Continuous pores
Nitrogen 0,220 Fistulas with a diameter of 1 to 5 mm Continuous pores
80%Nitrogen +20%Hydrogen 0,065 The number of fistulas has decreased Pore size and number decreased
50%Argon +50%Oxygen 0,056 No fistulas No pores
Oxygen 0,018 No fistulas Separate pores
Change in the nitrogen content in the
cut edges at different depths from the surface [30]
Plasma-forming environment
Steel grade / thickness, mm
Distance from the cut surface to the test level, mm
Content [N, %]
Air
VMSt3s / S = 9
0
0.025
0.05
0.075
0.10
0.15
0.20
0.30
0.40
0.50
0.60
Average value
8.7
0.53
0.095
0.015
0.005
0.005
0.006
0.009
0.005
0.005
0.006
0.85
is recommended, which reduces the nitrogen content to 0.018%.
The maximum value of nitrogen content in the gas-saturated layer depends on cutting conditions and can reach 0.2-0.5% [34]. Similar values of nitrogen concentrations were obtained in the work [30] at a depth of 0.025 mm.
In the presence of hydrogen, the absorption of nitrogen by steel slows down [36]. The rate of nitrogen desorption increases with an increase in the concentration of hydrogen in the gaseous medium to the power of 3/2. A positive effect of hydrocarbons on nitrogen fixation in the plasma jet is noted. Nitrogen binding in the presence of hydrocarbons in plasma was studied in detail in [37], where the regularities and efficiency of the process were established. In addition, the works [17, 38] show the high energy efficiency of plasma-forming mixtures of air with hydrocarbons.
The nitrogen content in the weld metal is affected by the polarity of the current [39]. When welding in reverse polarity, an electron cloud is created around the cathode, which prevents the formation of positive ions and reduces the possibility of dissolution of gases on the cathode.
Porosity is one of the main defects in welds. The formation of pores is associated with the conditions of saturation of the metal with gases and their release during crystallization [40, 41]. It is due to the supersaturation of weld pool metal with gases, the presence of conditions that favor the formation of gas bubbles and inhibit their removal from the liquid metal. The gases that cause pores in the welds are usually hydrogen and nitrogen, the solubility of which in the metal decreases with decreasing temperature, as well as oxygen, which forms gaseous products as a result of reaction with carbon and hydrogen.
It was shown in [30, 33] that one of the main causes of porosity in welds after air-plasma cutting of steels is an increase in the nitrogen content in the cut edges.
Various measures are recommended to prevent pores [33, 35, 42, 43]. It is recommended to use oxy-plasma cutting, adjusting the cutting mode parameters, of which the most effective way to reduce the likelihood of pore formation during welding is to reduce the cutting speed, air-plasma cutting using water and other measures, but their main disadvantage is the lack of stability of the results. For example, in [42] studies of airplasma and oxygen-plasma cutting were carried out and it was shown that on steels 09G2 (Q235) and 10ChSND, the use of oxygen-plasma cutting with a thickness of up to 12 mm does not exclude the formation of pores during submerged arc welding. This is explained by the fact that nitrogen enters the edges as a result of air suction into the plasma arc and the cut cavity. In [35], it is recommended to increase the arc voltage, reduce the cutting speed, use arc vortex stabilization and other measures to change the depth of the cast metal section at the cut edges. Investigations of the influence of the air + water plasma-forming medium on the quality of cutting have become the subject of research in this paper.
Currently, plasma torches are used for cutting in
an air plasma-forming medium with flat film cathodes with zirconium or hafnium axial cylindrical inserts. The need to fix the cathode spot of the cutting arc in the center of the end of such an insert requires stabilization of the arc by an intense vortex flow of compressed air, which causes uneven conditions for thermal action on the right and left edges of the cut [44]. The anode spot, rotating clockwise due to the kinetic energy of the plasma flow, cannot jump over the width of the cut. Due to the delay of the arc on the right edge of the cut, heat transfer to this side increases, which should affect the quality of the cut.
Conclusions.
1. During plasma cutting, a heat-affected zone (HAZ) is formed with areas of structural changes and a cast layer on the cut surface, which was formed by melt crystallization on this surface. The length of the cast section is determined by the interaction of the plasma jet with the molten metal and its oxides during the cutting process. In this area, a change in the chemical composition, saturation with gases (primarily nitrogen), the formation of cut roughness and an increase in the hardness of the metal being cut are observed. Minimizing the depth of the cast area reduces the roughness of the cut surface and the degree of unfavorable metallurgical changes in the properties of the parent metal at the cut edges.
2. The effect of various plasma-forming gases on the quality of plasma cutting is analyzed: air, nitrogen, 80% nitrogen + 20% hydrogen, 50% argon + 50% oxygen, oxygen. It has been established that the highest saturation of the cast layer with nitrogen (up to 0.20.5%) is observed when air is used. The negative effect of nitrogen saturation of the cut edges is manifested in a significant increase in their hardness, as well as in the formation of pores in the welds obtained during subsequent welding of the cut parts.
3. In the presence of hydrogen, the absorption of nitrogen by steel slows down. The rate of nitrogen desorption increases with an increase in the concentration of hydrogen in the gaseous medium to the power of 3/2. The binding of nitrogen in the plasma jet is positively affected by hydrocarbons. In addition, plasma-forming mixtures of air with hydrocarbons increase the energy efficiency of plasma cutting.
4. The depth of the cast section of low-carbon steels depends on the cutting speed and the conditions of flushing of the plasma melt formed on the frontal surface of the cut as a result of the melting action of the arc and the exothermic reaction of iron oxidation by oxygen of the air stabilizing it. To reduce the depth of the cast section, it is recommended to increase the plasma flow rate, which is accompanied by an increase in the voltage of the cutting arc with an increase in the flow rate of the plasma-forming medium, the use of nozzles of small diameter and with an increased length of the nozzle channel, the addition of water vapor to the cutting gas (compressed air), and an increase in the compression of the arc by a symmetrical jet water.
5. The state of the surface of the cut edges can affect the fatigue resistance of parts and structures made from parts after plasma cutting for two reasons: roughness on the cut surface acts as stress concentrators with
their inherent adverse manifestations; physical and chemical changes in the surface layers of the metal after plasma cutting can significantly affect the fatigue resistance of the metal.
Acknowledgements
The work was supported by the project: "Development and application of technology for plasma cutting c with the addition of water of steel sheets for shipbuilding", No. WSG2021012, China.
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EXPLORING THE FRONTEND INDUSTRY IN 2022: A COMPREHENSIVE ANALYSIS OF POPULAR TECHNOLOGIES, TOOLS, AND DEVELOPMENT PRACTICES
Kniazev I.
Senior Software Engineer at June Homes Istanbul, Turkey DOI: 10.5281/zenodo.7618447
ABSTRACT
In this article, I present the results of a survey that aimed to gain insight into the current state of the frontend industry. The survey was conducted with more than 3,700 participants from 125 countries. The survey results provide a comprehensive overview of the frontend industry in 2022. It includes information on the demographics of frontend developers, the types of projects they work on, the development methodologies they use, and the tools and technologies they use. The survey results reveal the popularity of JavaScript and React among frontend engineers, the widespread use of Agile development methodologies, and the increasing use of cloud-based platforms and third-party tools. These insights can help frontend developers, designers, and managers make informed decisions when it comes to choosing technologies, tools, and practices for their projects. Additionally, the article will cover the subject of vendors, looking at the platforms and third-party tools frontend engineers use for error tracking and monitoring. Overall, the article will be an invaluable resource for developers, designers, and managers who want to stay up-to-date with the latest trends and practices in the field.
Keywords: Frontend development, Technologies, Tools, survey, Frameworks, Development methodologies, JavaScript, Industry practices, Industry trends.
As technology continues to evolve at a rapid pace, it's essential for developers to stay up-to-date with the latest trends and practices in their field. Frontend development is no exception, with new technologies, tools, and frameworks emerging all the time. To gain a better understanding of the current state of the frontend industry, a survey was conducted with more than 3,700 participants from 125 countries. The survey aimed to gather insights into the demographics of frontend developers, the technologies and tools they use, and the engineering practices they follow. The results of the survey provide valuable insights into the current state of the frontend world, and can help developers make informed decisions when it comes to choosing technologies, tools, and practices for their projects.
The survey included questions about the respondents' demographics, such as their job title, location, and
company size. It also covered topics such as the types of projects frontend engineers work on, their development methodologies, and the tools and technologies they use. Additionally, the survey touched on the subject of engineering practices, such as version control systems, automated testing, and continuous integration and delivery.
The survey results provide a comprehensive overview of the frontend industry in 2022. They reveal the popularity of JavaScript and React among frontend engineers, the widespread use of Agile development methodologies, and the increasing use of cloud-based platforms and third-party tools. These insights can help frontend developers, designers, and managers make informed decisions when it comes to choosing technologies, tools, and practices for their projects.
