Blade Tools Research Articles

Cement slurry penetration behavior of swirl grouting technology

Traditional pressure grouting technology operates under steady pressure conditions, causing the grout to easily flow along preferential pathways. This results in uneven grout penetration and increased economic costs. This study proposes swirl grouting technology, which effectively improves this problem. To verify the effectiveness of swirl grouting, a fan-shaped blade tool was also proposed. The grout penetration performance was investigated through experimental studies. The length, width, height, weight, and uniformity of the grouted bodies produced by the swirl grouting method were compared with those produced by the steady pressure grouting method. Then, the mechanisms of swirl grouting were analyzed through transparent disc visualization experiments. The results demonstrated that, at different water–cement ratios, the swirl device increased the penetration length in the X, Y, and Z directions by 43.3%, 27.8%, and 45.8%, respectively, compared to the conventional straight device, and by 57.3%, 39.4%, and 55.6%, respectively, compared to the fan blade device. Moreover, the swirl device increased the weight of the grouted stone body by 54.9% compared to the conventional straight device and by 91.0% compared to the fan blade device, significantly enhancing filling efficiency. The uniformity coefficient of the swirl device permeation decreased by 56.6% and 51.0%, respectively, compared to the conventional straight device and the fan blade device, resulting in a more uniform grout distribution. The transparent disc visualization experiment further revealed the advantage of the swirl device in promoting the migration of fine particles, with a significant increase in average penetration distance and a penetration shape closer to a regular circle. The rotating flow path of the swirl device imparts additional rotational momentum and multidirectional penetration capabilities. The resulting turbulence accelerates the mixing of grout with the soil matrix, facilitating the migration of fine particles, expanding flow channels, and reducing flow resistance. This combination of effects enhances penetration efficiency and reduces energy loss. This study offers significant practical application value for improving engineering quality, construction efficiency, and reducing costs.

Surface Roughness Evaluation of AZ31B Magnesium Alloy After Rough Milling Using Tools with Different Geometries

This paper presents the experimental results of a study investigating the impact of machining parameters on 3D surface roughness after rough, dry milling. The following 3D roughness parameters were analysed: Sa (arithmetic mean height), Sq (root mean square height), Sz (maximum height), Sku (kurtosis), Ssk (skewness), Sp (maximum peak height), and Sv (maximum pit height). Roughness measurements were made on the end face of the specimens. Additionally, 3D surface topography maps and Abbot-Firestone material ratio curves were generated. Carbide end mills with variable rake and helix angles were used in the study. Experiments were conducted on AZ31B magnesium alloy specimens using a contact-type profilometer. The machining process was conducted using the parameters of so-called high-speed machining. Three variable technological parameters were analysed: cutting speed vc, feed per tooth fz, and axial depth of cut ap. The results showed that the surface roughness of the rough-milled specimens depended to a great extent on the tool geometry and applied machining parameters. Feed per tooth was found to have the greatest impact on surface roughness parameters. Lower values of the analysed surface roughness parameters (and therefore higher surface quality) were obtained (in most cases) for the tools with a rake angle γ of 5° and a helix angle λs of 50°. The results provided both theoretical and practical knowledge about the achievable surface roughness after rough milling using tools with different tool blade geometry. It was shown that rough milling is an effective and efficient type of machining for the AZ31B alloy.

THE DEVELOPMENT OF THE RESEARCH OF THERMAL PROCESSES IN MECHANICAL ENGINEERING TECHNOLOGY

A method for calculating the temperature in the surface layer of the work-piece with a blade tool is described, taking into account the volumetric heat source in the cutting zone, on the basis of which it is proposed to calculate the processing errors caused by thermal effects on the cutting tool and the workpiece. The results of calculations of the temperature in the surface layer of the part material are compared when calculating taking into account flat and volumetric heat sources. The peculiarity of the proposed method for determining the temperature in the surface layer of the workpiece is that the physical and mechanical properties of the processed and tool materials, processing modes, dimensions of the workpiece and cutting tool, geometry of the cutting part of the tool are taken into account. The calculations take into account the change in the intensity of volumetric heat flows in the cutting zone according to their height.

A wear testing method of straight blade tools for Nomex honeycomb composites machining

Ultrasonic vibration machining (UVM) with a straight blade tool (SBT) is currently an efficient process for part manufacturing of Nomex honeycomb composites (NHCs) in the aerospace industry. To solve the wear evaluation problem of SBT, this study focused on the failure characteristics of tool edge blunting, which was different from that of traditional metal-cutting tools. The edge radius measured by ultra-depth microscope and a dimensionless parameter Bluntness Coefficient (CB) obtained from fiber-cut sharpness test were applied to evaluate SBT wear. The fiber-cut sharpness test was realized by a two-stage model proposed based on fiber failure analysis and force-displacement curve, which were validated by experiments. A standardized testing device was established based on the model, and a relationship between edge radius and CB was obtained by testing quantitatively blunted SBTs. Machining experiments were carried out to obtain a correlation between tool performance and CB, and a failure standard of CB value for SBT was proposed. It was demonstrated that CB was an efficient indicator for SBT wear evaluation, and the sharpness testing by cutting fibers could characterize SBT wear with favorable accuracy and repeatability.

Determination and Analysis of Working Diameters and Working Angle of the Torus Cutter Blade in Multi-axis Machining in the Aspect of Tool Wear

The aim of this study is to provide a theoretical and experimental analysis of the multi-axis milling process by the torus milling cutter of nickel-based superalloy parts in terms of surface quality and tool wear. In the analytical part, using, among other things, matrix calculus and trigonometric relationships, mathematical models were developed to describe the relationships between the tool axis orientation and the geometric parameters of the cutting layer at the contact point. On this basis, mathematical relationships for contact diameter and effective diameter were derived. The basis for these considerations is the very rarely considered working angle of the cutter blade. In part of the experimental study, machining tests were carried out for selected kinematic variants of multi-axis cutting. Based on the results obtained, it was found that as the tool axis inclination angle increases, the contact diameter increases. The effective diameter at the upper characteristic point of the cutting layer increases up to a certain angle of inclination, after which it begins to decrease. The rotational angle of the tool axis does not affect any of the diameters, but it does affect the displacement of the contact point, the values of the working angle of the tool blade and the feed-related component decrease. The result of this displacement is a change from climb milling to conventional milling, which has significantly degraded surface quality and tool life. The best results of the machining test were obtained when only the angle of inclination of the tool axis was used. It was concluded that the parameter tool blade working angle can be a control variable in a multi-axis milling process and has a major impact on the physical aspects of the cutting process.

Dominating influence of cutting-edge lead angles on arc-trajectory machining of Nomex® honeycomb composites by using a straight blade cutter

Nomex® honeycomb composites (NHCs) with circular arc features are a challenging issue in the machining of aviation curved structural components. Compared to linear feature machining, arc feature machining involves six-axis coordinated motion, introducing additional variables. Directly referencing the linear feature machining process will lead to the deterioration of contour accuracy and surface quality in arc-trajectory machining (ATM). To further explore the influence of process variables on ATM, this study developed an error model for straight blade tool (SBT) ATM and investigated the influence of cutting-edge lead angles (γ) on contour accuracy and surface quality. A vertical cutting process was proposed, and experiments proved it provided the optimal machining quality (the defect rate of core cells was only 3.93 %) compared to forward and backward inclination cutting (7.23 %∼34.3 % and 9.71 %∼17.36 %, respectively). Additionally, it was revealed that the main reason for the deterioration of surface quality on ATM was the excessive angle between the cutting edge direction and the feed direction. Based on the results above, the influence and optimization of cutting-edge lead angles were revealed, and the advantage of vertical cutting process for machining NHCs with arc-trajectory was demonstrated. This research provides a feasible method for the machining of NHCs with arc-trajectory using SBT.

Многокритериальная оптимизация операционных режимов технологических процессов

The issues that are rarely combined in one small study are viewed. First of all, this is a well-known problem of engineering support of a specified quality of hardened steels surface layer using a blade tool made of superhard materials and the state of microclimate of operating areas of metal-cutting machines. It had a shot at creating a mathematical model that combines these two objective functions. As a mathematical tool that allows optimizing the modes of finishing and fine turning, the linear- programming technique was applied, which visualises through its graphic image, a picture of the influence of the engineering constraints included in the model on the optimal values of the cutting speed and feed. On the basis of analytical studies, the dependences of the formation of hydrogen sulfide vapors in the operating areas of metal-cutting machines using sulfofresols of various brands as lubricating and cooling fluids were obtained. Theoretically, it has been established that the maximal influence on the intensity of hydrogen sulfide vapor formation is exerted by the temperature in the cutting zone, which is more effected by the lathe turning speed. The paper presents empirical dependencies ratios that allows finding an average temperature in the cutting zone in the process of various steels treatment, as well as high-strength alloys and non-ferrous alloys. The roughness and the degree of cold work coefficient were taken as parameters of the surface layer condition for cylindrical surfaces, which decisively determine the durability of the products under conditions of friction and cyclic loads. Testing of the obtained mathematical models made it possible to obtain optimal values of feed and cutting speed for finishing and fine turning of hardened steels 45 and 65G.

Scientific Basis for the Substantiation of Process Regulations for the Micro-Cutting of Hardened Gears

Abstract The paper considers scientific principles of technological procedure development for the selection and assignment of parameters of velocity machining by blade tool at gear milling with due regard to the required parameters of the gear surface layer. Optimum micro-cutting conditions are determined when full participation in stock removal of all mill teeth is provided. Technological regulation of selection and setting of machining parameters is spread for gear hobbing of the spur gear wheels with fine-modular and coarse-modular hardness (220...320 HV) and after heat treatment (HRC46...63). Correlation with essential parameters of the surface layer, cutting depth, feed, speed and radius of rounding of the cutting edge of milling cutters’ teeth is established. It is scientifically grounded, tested, and proved at what modes of cutting, the radius of rounding of cutting edge of the cutting tool is made metal removal at oncoming and passing high-speed micro milling. The process of determining of minimal sliding angle, or maximum value (without the use of coolant and with coolant), in which there is no micro-cutting process taking into account variation of variable parameters of cutting conditions and geometrical parameters of hobbing cutters is modelled. For the first time, we ascertained the relation between the sliding angle and the maximum contact angle of the mill tooth with the work surface, which allowed determine the efficiency of the shaping process through coefficient (without coolant and with coolant).

Influence of cutting parameters and tool nose radius on the wear behavior of coated carbide tool when turning austenitic stainless steel

This study investigated the wear behavior of coated carbide tool with different tool nose radius under different cutting parameters when turning AISI 321 austenitic stainless steel. The full factorial turning experiments with three factors and two levels cutting parameters were carried out. The wear progression of the tool with cutting time was recorded. The tool wear mechanism and the influence of cutting parameters and tool nose radius on the tool wear behavior were analyzed. The results showed that the cutting tool mainly exhibited wear manners of abrasive wear, adhesive wear, and oxidation wear. The tool life varies a lot with the cutting parameters, with the feed rate the most sensitive. Decrease the nose radius makes the strength of the tool blade worsened, thereby increasing the tool life sensitivity to cutting parameters. However, decreasing the tool nose radius can effectively increase the tool life. The reason is that when the tool nose radius is reduced, the cutting temperature can be decreased and at the same time the chip breaking performance can be improved, which decrease the mechanical damage of chips to the tool and related wear, and thus resulting in a longer tool life.

The Effect of the Surface Topography of High-Speed Steel Cutting Blades Made Using Various Methods on Their Technological and Functional Properties.

Indication of the proper scope of application of high-speed steels (HSS) produced by conventional methods and powder metallurgy for cutting tool blades requires a thorough assessment of their properties in various cutting conditions. According to common knowledge, the properties of tools made of both types of steel are largely determined by the arrangement of carbide phases. It turns out, however, that the surface morphology of the cutting blades is at least as important for their operational properties. This was already indicated by the preliminary research of the authors of the article, in which it was found that the surface topography significantly affects their durability depending on the applied value of the cutting speed in dry machining conditions and in the presence of a cooling lubricant. As it turned out, contrary to the literature data, blades made of sintered HSS do not have better service properties in all cutting conditions than blades made by conventional methods (e.g., in forging and hot rolling processes). Hence, it was necessary to determine the justified range of use of both types of steel for cutting blades. Cutting blades with a similar chemical composition from conventional high-speed steel and those produced in the powder metallurgy process were tested. Wear curves were determined on the basis of the tests. On this basis, for the assumed value of the blunting index, the tool life of the cutting edges was determined during the cutting of selected structural steel, commonly used for high-strength machine parts. Tests of the cutting ability of the blades were carried out without and with the use of a cooling--lubricating liquid. In order to correctly interpret the obtained results of the wear and durability tests of the cutting edges, verification tests were carried out. A detailed analysis of the research material made it possible to determine the recommended range of applicability of conventional and sintered HSS for the tested case.

Micro milling of fused silica using picosecond laser shaped single crystal diamond tools

Fused silica is widely used as a material for optical lenses owing to its excellent optical properties and low thermal expansion coefficient. However, as a hard and brittle material, there is very limited option of processing technologies to machining fused silica with surface structures. In this paper, a picosecond laser based single crystal diamond tool fabrication technology is proposed to generate micro milling tools with different geometrical designs, and the tool cutting performance is experimentally tested through micro-milling of fused silica under different cutting conditions. An optimal picosecond laser processing path is proposed to inhibit the graphitization of diamond tool and improve the concentricity of tool blades, and a multi-edge milling tool with a minimum rotary diameter of 0.4 mm can be obtained. The effects of rake angle on cutting force and the degree of brittle damage on the subsurface of fused silica are studied by micro milling tests of fused silica using the laser-shaped tools. The results show that the fused silica machined by diamond milling tool with a rake angle of −30° has the best surface finish (Ra = 41.2 nm). Using this laser-machined milling tool, a plurality of micro Fresnel lenses with aperture of 1.6 mm were successfully machined on a fused silica sheet.

MP13-12 A COMPARISON OF THE EFFICIENCY AND SAFETY PROFILE BETWEEN TWO MORCELLATORS FOR LASER ENUCLEATION OF THE PROSTATE: PIRANHA VERSUS CYBER BLADE DEVICES

You have accessJournal of UrologyCME1 Apr 2023MP13-12 A COMPARISON OF THE EFFICIENCY AND SAFETY PROFILE BETWEEN TWO MORCELLATORS FOR LASER ENUCLEATION OF THE PROSTATE: PIRANHA VERSUS CYBER BLADE DEVICES Lorenzo Berti, Davide Perri, Federica Mazzoleni, Andrea Pacchetti, Elena Morini, Umberto Besana, Antonello Paulesu, Maria Chiara Sighinolfi, Bernardo Rocco, Jean Baptiste Roche, Evangelos Liatsikos, Franck Bruyere, and Giorgio Bozzini Lorenzo BertiLorenzo Berti More articles by this author , Davide PerriDavide Perri More articles by this author , Federica MazzoleniFederica Mazzoleni More articles by this author , Andrea PacchettiAndrea Pacchetti More articles by this author , Elena MoriniElena Morini More articles by this author , Umberto BesanaUmberto Besana More articles by this author , Antonello PaulesuAntonello Paulesu More articles by this author , Maria Chiara SighinolfiMaria Chiara Sighinolfi More articles by this author , Bernardo RoccoBernardo Rocco More articles by this author , Jean Baptiste RocheJean Baptiste Roche More articles by this author , Evangelos LiatsikosEvangelos Liatsikos More articles by this author , Franck BruyereFranck Bruyere More articles by this author , and Giorgio BozziniGiorgio Bozzini More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003233.12AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Different types of morcellator by different companies are available on the market with different features. However, the type of morcellator which provides the best performance has not been found yet and evidence on the comparison between these tools is still scarce. We performed a comparison between the Wolf® Piranha™ and the Quanta System®Cyber Blade™ instruments for the Thulium laser enucleation of the prostate (ThuLEP). METHODS: 205 patients suffering from lower urinary tract symptoms due to benign prostatic hyperplasia underwent ThuLEP using the Cyber TM laser generator between 2020 and 2022. All surgeries were performed by the same operator. Morcellation was performed with the Piranha morcellator in 100 cases (Group A, 48.8%) and the Cyber Blade morcellator in 105 cases (Group B, 51.2%). Morcellation time and efficiency were recorded relating instrument performance to prostate volume. Complication rate and device malfunctions were reported to assess safety of these instruments. RESULTS: Groups were comparable according to preoperative features. Mean prostate volume (PV) was 82.5 ml and 91.9 ml (p=0.21) in Group A and B respectively. Mean morcellation time was 9.7 min and 10.1 min in Group A and B respectively when PV was ≤100 ml, with no statistically significant difference (p=0.34). On the contrary, mean morcellation time was significantly lower in the Cyber Blade group vs the Piranha group when PV was >100 ml (12.7 min vs 10.1 min, p=0.04). Similarly, morcellation efficiency was comparable when PV was ≤100 ml (8.5 g/min vs 9.1 g/min, p=0.08), while it was significantly higher in the Cyber Blade group when PV was >100 ml (7.0 g/min vs 9.3 g/min, p=0.04). Bladder injury occurred in 3 cases (3.0%) in Group A and 2 cases (1.9%) in Group B. Both morcellators had comparable complication rate (p=0.12). No mechanical problems occurred. CONCLUSIONS: Performance was similar in terms of morcellation time and efficacy between Piranha and Cyber Blade tools when PV was ≤100 ml, while it was significantly higher with the Cyber Blade morcellator when PV was >100 ml. Both instruments are safe and reliable according to the risk of bladder injury and the occurrence of mechanical problems. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e177 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Lorenzo Berti More articles by this author Davide Perri More articles by this author Federica Mazzoleni More articles by this author Andrea Pacchetti More articles by this author Elena Morini More articles by this author Umberto Besana More articles by this author Antonello Paulesu More articles by this author Maria Chiara Sighinolfi More articles by this author Bernardo Rocco More articles by this author Jean Baptiste Roche More articles by this author Evangelos Liatsikos More articles by this author Franck Bruyere More articles by this author Giorgio Bozzini More articles by this author Expand All Advertisement PDF downloadLoading ...

Elucidation of the mechanism of chatter mark formation during end-milling and inverse analysis of chatter vibration by two-dimensional discrete Fourier transform of chatter mark

Regenerative chatter vibration is a typical machining problem during cutting. The frequency and phase shift of regenerative chatter can be used as indicators to suppress regenerative chatter. However, direct measurement of chatter vibration during cutting is difficult for end milling because the tool blade rotates. Therefore, chatter vibration is generally measured indirectly, for example, from cutting noise or vibration transmitted to the spindle. The type and position of the installed sensors must be appropriately selected to accurately measure chatter vibration with these methods. This selection must account for the machine tool structure, cutting conditions, and the position where the chatter vibration occurs, making the measurement methods not universally applicable. When chatter vibration occurs during cutting, a periodic pattern called a chatter mark is formed on the machined surface. The chatter mark is formed by vibration during cutting, i.e., vibration information during cutting is directly recorded. Therefore, this paper proposes a method to analyze the frequency and phase shift of chatter vibration using a two-dimensional discrete Fourier analysis of the chatter mark based on the modeled formation mechanism of chatter marks, and further validates the proposed method by elucidating the mechanism of chatter mark formed by chatter vibration. First, a cutting simulation was performed based on the vibration displacement of the tool during chatter cutting obtained experimentally. This simulation elucidates the mechanism by which the vibration information of chatter vibration can be analyzed from the chatter mark. Subsequently, the chatter vibration parameters were analyzed from the chatter mark using the proposed method. The parameters were consistent with those analyzed from the vibration displacement of the tool, confirming the effectiveness of the proposed method.

Design, research, and production of gear wheels for mining machines

The current state of the Ukrainian fuel and energy complex requires a continuous increase in coal production. As part of concept implementation for the coal industry development now created and introduced into serial production a new generation of mining machines. The most loaded element of mining machine is its gear wheels of cutting part. Calculations for the strength and durability of gearings have been carried out. The modelling of the teeth stress-strain state by the finite element method has also been carried out. Works were carried out on the processing of parts of gearboxes of mining machines. Investigations of the processes of blade processing of gears and shafts of gearboxes of coal combines were carried out. The state of the surface layer, the quality and accuracy of processing these parts with a blade tool made of superhard materials are determined. Researches of grinding of an involute profile of gear wheels of gearboxes of mining machines are carried out. A study was made of the surface quality and accuracy of gears after grinding with special abrasive wheels. The influence of processing processes with a tool made of superhard materials on the strength and durability of gear drives of mining machines is determined.

Interactive methods for increasing wear resistance of cutting tool blades

In the scientific work, the features of the structure of the near-surface layer of high-speed steel R6M5, complex processing modified by the methods of the first ion-nitriding, ion alloying of the surface, and wear-resistant coating, its effect on the wear resistance of the tool during dry cutting of hard-to-cut chromium and its alloys are considered. One of the promising directions for hardening tools made of high-speed steel is the creation of layered structures on their surface with a gradient of physical and chemical properties between wear-resistant coatings and the base material. Among the methods for such surface modification is a special process based on the use of high-intensity pulsed beams of charged particles. Ion-nitriding treatment was carried out on the APP-2 unit, ion-alloying treatment was carried out on the unit, the latter with low friction coating. The advantage of this device is that it coats the Nb and Hf elements on the surface of the cutting tool, heats up to 10 6 deg/s in 5 μs, causing the two elements to diffuse into the cutting tool. The last treatment on the basis of reinforced cutting tools is coated with PLATIT π311 (TiAl)N. As a result, the stability of the cutting tool has increased by 3-4 times. The study was conducted at the Navoi Machine-Building Plant and conclusions were drawn.

K-type flint in Final Eneolithic Lesser Poland

Studies of artefacts from Corded Ware culture graves in western Lesser Poland have demonstrated that raw materials originating from the eastern Świętokrzyskie region take a leading role: Świeciechów flint (for the production of axes), and chocolate flint (for making flake and blade tools). New data obtained through the study of settlement sites in the vicinity of Kraków have highlighted the significant role of another hitherto little-noticed raw material: K-type flint (otherwise known as the Wielka Wieś type). This raw material was used mainly for the production of core tools. Workshops producing axes from this flint were discovered on the right bank of the Vistula River in the area between Kraków-Bieżanow and Zakrzów. Tools made from K-type flint appear in Final Eneolithic graves north of Kraków as well, and another production centre is known from this region, near Ojców. The provenance of the raw materials used in the vicinity of Ojców and in the Kraków-Bieżanów - Zakrzów area remains undetermined. Hypothetically, two deposits with different locations were used. In light of new discoveries made during large-scale rescue research projects, the raw material preferences in Final Eneolithic Lesser Poland seem more complex than previously believed, and they varied from micro-region to micro-region.

Marketing Communication and Reputation Building of Leading European Oil and Gas Companies on Instagram

The overall transition towards a low-carbon economy is expected to pose a solution for several global problems, including the ongoing climate change while ensuring economic and social development. Large oil and gas companies are aware of the need to transform their business, turn to renewable and clean energy sources to build a positive image and reputation, and have the economic power to do so. This paper aims to evaluate the marketing communication of leading European oil and gas companies on their Instagram accounts in the context of reputation building through using social media and identify to what extent the companies reflect the environmental aspects of corporate social responsibility. Content analysis and the Social Blade tool were used to examine the marketing communication of the five biggest companies by revenue. All the companies are active on Instagram, but it has been found that the Russian companies have remained inactive and have even been losing followers since March 2022, when the war conflict in Ukraine started. Surprisingly, Shell uploaded only a few posts during the reference period but is recognized as the company achieving the highest social media effectiveness. Although all observed oil and gas companies continue their business as usual, they incorporate and communicate efforts to support the development of electromobility, clean and renewable energy projects, as well as ecological projects.

Increasing the reliability of a bladed tool made from synthetic polycrystalline diamonds

The results of static and dynamic 3D modeling of the cutting process with a blade tool made of synthetic polycrystalline diamonds (PCD) are presented. Theoretical studies using the DEFORM-3D and COSMOSWorks software packages made it possible to study the influence of the bond's properties, the presence of metal phase inclusions in the structure of synthetic diamonds (their number, composition and size) and the temperature in the cutting area on the stress-strain state (SSS) of the studied “cutting edge – metal phase” system. The level of SSS was estimated by determining the maximum values of equivalent stresses in the places of accumulation of metal inclusions, the thermal expansion coefficient of which is much higher than that of diamond. A method for sharpening cutters with PCD blades is proposed to ensure reliability at the manufacturing stage (sharpening).

Особенности применения ультразвука при плазменно-механической обработке деталей из труднообрабатываемых материалов

Introduction. Structural materials, including materials made of heat-resistant and hard-to-work steels, are widely used in various branches of mechanical engineering. To increase the efficiency of manufacturing parts of thermal equipment from heat-resistant and hard-to-work steels, the technological method of cutting with preliminary plasma heating of the workpiece is used. There is also a technological method of cutting metals, including hard-to-process materials by ultrasonic turning. Proceeding from this, in order to increase the efficiency of plasma machining of hard-to-process materials, it is necessary to investigate the technological possibilities of using ultrasonic turning of hard-to-process materials during plasma machining. The purpose of the work: to investigate the wear of cutting tools when using ultrasound in the conditions of plasma-mechanical processing of parts made of hard-to-process materials. The paper investigates the features of the plasma-mechanical processing under ultrasonic cutting conditions and determines the wear values of carbide cutters VK8, T5K10 and T15K6 when processing steels of grades 20Cr13Ni18 and 20Cr25Ni20Si2(cast). And also the wear of these cutters was determined under the conditions of conventional turning of the same materials to compare the results of wear of the cutters in different processing conditions. The research method is to determine the linear wear of carbide cutters along the back surface with conventional, plasma-mechanical and plasma-mechanical cutting assisted with ultrasonic cutting using an instrumental microscope and visual estimation with a 10x magnifying glass. Results and discussion. The paper presents the results of experimental studies to determine the wear of cutting tools when processing heat-resistant steels of the 20Cr13Ni18 and 20Cr25Ni20Si2(cast) grades with carbide cutters of the VK8, T5K10 and T15K6 grades. Studies were carried out to determine the wear of carbide cutters as with conventional mechanical cutting, plasma-mechanical cutting, as well as plasma-mechanical cutting using ultrasound. The experiments were carried out when turning these materials on a modernized lathe mod.1A64. A rectifier with a controlled choke and a plasma torch mod.APR-403 are connected to the lathe; a plasma holder is placed on the lathe carriage. A semiconductor rectifier serves as a power source with a compressed electric arc of current. The arcing takes place between the cathode (plasma torch) and the anode (blank) at the point of the plasma-forming gas; compressed air passes through the nozzle channel of the plasma torch. During the experiments, the position of the plasma torch was adjusted relative to the part rotation axis. When conducting experiments on studying the wear of cutters under conditions of ultrasonic plasma-mechanical cutting, ultrasound was applied to the cutting edge using a device developed by the authors. When processing heat-resistant steels under the usual turning condition, processing modes were adopted: cutting speed V = 10 m/min, cutting depth t = 3...4 mm, longitudinal feed Sl = 0.31 mm/rev. It is found that when processing steel grade 20Cr13Ni18 by conventional cutting, the back surface of the carbide cutter made of T5K10 wears out to 1 mm in size within 10 minutes, and for the cutter made of VK8 – within 15 minutes. During plasma machining, the cutting speed and the feed rate were increased 2 times; the results of the wear of the cutters show that at the same time T5K10 wears out to 1 mm within 20 minutes, VK8 – within 25 minutes. Plasma-mechanical processing using ultrasound show that the carbide cutter T5K10 wears out by 0.50 mm in less than 50 minutes of cutting, and VK8 wears out by 0.35 mm. The same results are obtained when processing heat-resistant steel 20Cr25Ni20Si2(cast). Thus, the study of wear of carbide cutters in the processing of heat-resistant steels shows that the use of ultrasonic cutting in plasma-mechanical processing of steels can significantly reduce the amount of tool wear. The presented results confirm the prospects of using ultrasonic plasma-mechanical cutting of heat-resistant steels with blade tools.

Carbide Tool Wear Analysis for Manufacturing Aisi 4140 Alloy Steel with 2D/3D Deform Simulation in PT Rejeki Sekawan Abadi

The lathe process is a machining process that is most widely used and is very commonly used in an industrial field. During the turning process, the lathe will cut the workpiece with the main movement being rotating so that the workpiece can be slowly reduced in diameter. There are several parameters in the turning process such as feed rate, cutting speed and cutting depth. Parameter optimization in the cutting process is very necessary in order to reduce the cutting force during the machining process. If the cutting force is high, it can cause the tool ability to be reduced. In this study using three turning parameters, namely spindle rotation rate, feeding depth, and feed or chisel distance in 1 rotation of the workpiece. This can be seen from the simulation results, the results of simulation-2 and simulation-4 with a feed rate of 0.1 mm/rad with two other different parameters, the value of the depth of tool wear is 0.00487 and 0.00410 mm, then in simulation-1 and simulation -3 with the same feed rate value of 0.2 mm/rad and with two other different parameters, the depth of tool wear is 0.0117 and 0.00932 mm, respectively. With these results, it can be seen that the feed rate has quite an effect on the depth of tool wear during the turning process. Based on the results of the study, it can be concluded that the variation of the parameters that are simulated in the turning process can affect the condition of the tool blade used. When running the machining process with inappropriate parameters, it will cause tool failure or tool blade damage. Therefore, the lathe parameters must be considered.