Processing condition setting system

Abstract

The present invention is a processing condition setting system, more specifically comprising a cutting section equipped with a tool on one side, a measuring section for measuring a sound generated during cutting in the cutting section, and a control section for receiving and analyzing a measurement value from the measuring section and controlling the cutting section, wherein the control section is characterized by varying the feed rate, axial cutting depth, or rotational speed of the tool when the measurement value from the measuring section exceeds a preset reference value.

Description

Technology Field

[0001] The present invention relates to a processing condition setting system, and more specifically, to a processing condition setting system that derives optimal processing conditions based on the ratio of the loudness of a sound generated during a cutting process and the material removal rate. Background Technology

[0002] Machines used for the purpose of processing metallic or non-metallic materials into specific shapes and dimensions using appropriate tools via various cutting or non-cutting methods, or for performing more precise processing on semi-metals, are called machine tools. For example, Korean Registered Patent Publication No. 10-2686871 (July 19, 2024) discloses a cutting device for a pipe-type frame member.

[0003] Meanwhile, field experts performing cutting operations determine feed rates, axial depth of cut, and rotational speeds based on the sounds of the machine to ensure stable machining. However, there is a lack of research aimed at measuring and quantifying these factors. Here, machining conditions directly affect the efficiency and stability of the cutting process. In particular, duplex stainless steel, used in oilfield drills and rockets due to its high mechanical strength, weldability, and corrosion resistance, is suitable for high-temperature plastic deformation. However, as a representative high-strength, difficult-to-machine material, it requires high cutting forces and causes rapid tool wear, which poses a problem. Prior art literature

[0004] Korean Patent Publication No. 10-2686871 (July 19, 2024) The problem to be solved

[0005] The present invention was devised to solve the problems of the prior art described above. Its purpose is to provide a machining condition setting system capable of maximizing the efficiency of cutting operations by measuring the sound generated during cutting operations, measuring the sound changes while modifying machining conditions such as the tool feed rate, cutting depth, and rotational speed, deriving the material removal rate and non-cutting sound volume from the measured sound, and verifying a mathematical formula for the non-cutting sound volume to set machining conditions in a direction that reduces the non-cutting sound volume, thereby minimizing vibrations between the tool and the material that cause tool wear and maximizing the volume of material removed per hour.

[0006] The problems that the present invention aims to solve are not limited to those mentioned above, and other problems that the present invention aims to solve that are not mentioned herein will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0007] A machining condition setting system according to a preferred embodiment of the present invention comprises a cutting machine having a tool on one side, a measuring unit for measuring a sound generated during cutting of the cutting machine, and a control unit for receiving and analyzing a measurement value from the measuring unit and controlling the cutting machine. The control unit is characterized by varying the feed rate, axial cutting depth, or rotational speed of the tool when the measurement value from the measuring unit exceeds a preset reference value.

[0008] In addition, the control unit according to a preferred embodiment of the present invention derives the non-cutting noise amount based on the measurement value of the measurement unit and [Equation 1] Non-cutting noise amount = Measurement value of the measurement unit (dB) - Weight × 10log(MMR), (MMR = Material Removal Rate, Weight = Weight), and when the measurement value of the measurement unit exceeds a preset reference value, it is characterized by varying the feed speed, axial cutting depth, or rotational speed of the tool so that the non-cutting noise amount is reduced.

[0009] In addition, the control unit according to a preferred embodiment of the present invention is characterized by gradually reducing the feed rate of the tool while keeping the axial cutting depth and rotational speed of the tool fixed when the measured value of the measuring unit exceeds a preset reference value.

[0010] In addition, the control unit according to a preferred embodiment of the present invention is characterized by gradually reducing the axial cutting depth of the tool while keeping the feed speed and rotational speed of the tool fixed when the measured value of the measuring unit exceeds a preset reference value.

[0011] In addition, the control unit according to a preferred embodiment of the present invention is characterized by gradually reducing the rotational speed of the tool while keeping the feed speed and axial cutting depth of the tool fixed when the measured value of the measuring unit exceeds a preset reference value. Effects of the invention

[0012] By means of the solution to the above problem, the machining condition setting system of the present invention measures the sound generated during cutting, measures the sound changing while changing machining conditions such as the tool feed rate, cutting depth, and rotational speed, derives the material removal rate and non-cutting sound volume from the measured sound, and verifies a mathematical formula for the non-cutting sound volume to set machining conditions in a direction that reduces the non-cutting sound volume, thereby minimizing vibration between the tool and the material that causes tool wear and maximizing the volume of material removed per hour, and thus provides a machining condition setting system capable of maximizing the efficiency of cutting.

[0013] The effects of the present invention are not limited to those mentioned above, and effects of the present invention not mentioned herein will be clearly understood by those skilled in the art to which the present invention belongs from the description below. Brief explanation of the drawing

[0014] FIG. 1(a) is a diagram showing the configuration of a processing condition setting system according to an embodiment of the present invention, and FIG. 1(b) is a flowchart showing the processing condition setting process. FIG. 2 shows the result of summarizing the sound level measured through the measuring unit in a processing condition setting system according to one embodiment of the present invention. FIG. 3 shows the result of calculating and organizing the non-cutting sound amount based on the sound level measured through the measuring unit in a processing condition setting system according to an embodiment of the present invention. Specific details for implementing the invention

[0015] The terms used in this specification will be briefly explained, and the invention will be described in detail.

[0016] The terms used in this invention have been selected based on currently widely used general terms while considering their functions within the invention; however, these terms may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Therefore, the terms used in this invention should be defined not merely by their names, but based on their meanings and the overall context of the invention.

[0017] When a part of a specification is described as “comprising” a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0018] Embodiments of the present invention are described below with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0019] Specific details regarding the problem to be solved by the present invention, the means for solving the problem, and the effects of the invention are included in the embodiments and drawings described below. The advantages and features of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the accompanying drawings.

[0020] Increasing the feed rate directly boosts productivity, but it is an important machining condition that increases vibration and tool wear if excessive. Therefore, field experts establish stable and highly productive machining conditions by starting from the recommended conditions provided by tool manufacturers, checking for abnormal noise from the workpiece or tool through hearing, and gradually increasing the feed rate.

[0021] The setting of axial depth is also a factor that significantly affects productivity; while it is best to set it to the maximum possible depth, excessive machining depth can cause vibrations that may damage the tool insert. Therefore, the depth is gradually increased by auditory inspection to determine if there is any vibration at the tool manufacturer's recommended depth. This minimizes vibration between the tool and the material, and maximizes the volume of material removed per hour, thereby increasing roughing efficiency.

[0022] Spindle speed directly affects chatter and tool life. Since spindle speed does not directly impact productivity when feed rate and depth of cut are fixed, users experiment by adjusting the speed up or down from the tool manufacturer's recommended values ​​to find the spindle speed that produces the most stable sound. By using spindle speeds with low noise and vibration, users expect a longer tool life.

[0023] Hereinafter, the present invention will be described in more detail with reference to the attached drawings.

[0024] Referring to FIG. 1 (a), a processing condition setting system according to a preferred embodiment of the present invention comprises a cutting processing unit (100) having a tool on one side, a measuring unit (200) for measuring a sound generated during cutting processing of the cutting processing unit (100), and a control unit (300) for receiving and analyzing the measurement value of the measuring unit (200) and controlling the cutting processing unit (100).

[0025] First, the above-mentioned cutting section (100) is provided. The above-mentioned cutting section (100) can be provided in any form as long as the material can be cut using the above-mentioned tool. For example, the above-mentioned cutting section (100) may be a Hyundai WIA F500 / 50 machining center, the spindle and the holder are connected by a BT50, the shank protrusion length fixed to the holder with a collet and screw is 69.8 mm, the machining path reciprocates in a zigzag pattern with linear feed, arc feed, and linear feed on a flat surface, an inclined curved surface, and a flat surface, respectively, the path interval is fixed at 1 mm, and water-soluble cutting fluid is sprayed between the material and the tool at high pressure. In addition, the above material is duplex steel with dimensions of 180 x 114 x 59 mm, and consists of a slanted surface with a radius of curvature of 250 mm connecting a flat surface with a height of 59 mm and a flat surface of 40 mm on the left, a flat surface with a height of 20.5 mm and a flat surface of 64.5 mm on the right, a height difference of 38.5 mm between the high and low flat surfaces, and a horizontal distance of 75.5 mm. The above tool is a ball end mill, and a ball end mill is suitable for simultaneously machining a duplex with a slanted surface and a horizontal surface having an average slope of 0.51. It is provided as a roughing ball end mill for stainless steel machining recommended by TaeguTec, and the shank specification is 20-13-W25-L150, with a tool diameter of 20 mm, a cutting height of 13.6 mm, a diameter of 25 mm up to a shank length of 45.7 mm, and a diameter of 25 mm up to a shank length of 150 mm. The insert specifications are 2FB 200-ML, and TT8080 coating (TiAlN coating) is applied. The conditions recommended by tool manufacturer TaeguTec for milling duplex using a 20 mm diameter roughing cutter are a cutting speed of 80 - 100 m / min, a feed rate of 0.05 - 0.1 mm / tooth, and a depth of 1 - 2 mm.

[0026] Next, the measurement unit (200) is provided. The measurement unit (200) can be provided in any form as long as it can measure the sound generated during the cutting process of the cutting part (100). For example, it may be configured to include a noise sensor installed around the cutting position that generates a voltage difference determined by the noise amplitude when noise is generated, and an A / D converter connected to the noise sensor that converts an analog signal into a digital signal. For example, the measurement unit (200) is a noise meter of the TES 53H model, and a field expert with 20 years of experience uses the measurement unit (200) to measure the noise generated during the cutting process. The measurement value of the measurement unit (200) is transmitted to the control unit (300), and based on this, the control unit (300) can vary the feed rate, axial cutting depth, or rotational speed of the tool to derive optimal processing conditions.

[0027] Next, the control unit (300) is provided. The control unit (300) receives and stores the measurement value of the measurement unit (200), and if the measurement value of the measurement unit (200) exceeds a preset reference value, it varies the feed speed, axial cutting depth, or rotational speed of the tool. More specifically, the control unit (300) derives the non-cutting noise amount based on the measurement value of the measurement unit (200) and the following [Equation 1], and if the measurement value of the measurement unit (200) exceeds a preset reference value, it varies the feed speed, axial cutting depth, or rotational speed of the tool so that the non-cutting noise amount is reduced.

[0028]

[0029] SCSL = Non-cutting noise, MMR = Material Removal Rate, Weight = Weight

[0030] In this invention, the value obtained by dividing the sound level by the Material Removal Rate (MRR) is defined as the Specific Cutting Sound Level, and the relationship between the Specific Cutting Sound Level and the method for setting processing conditions based on noise at the site is investigated. Specifically, the value of [Equation 2] below, obtained by subtracting the 10log(MRR) value from the sound level, is monitored to see how it changes during the process of setting processing conditions at the site.

[0031]

[0032] Here, MRR represents the material removal rate, and multiplying it by the specific cutting energy yields the energy required for cutting per hour. Since a higher proportion of cutting energy released as sound due to vibration indicates unstable cutting, machining conditions with a low specific cutting noise, calculated by dividing the cutting noise by the material removal rate, are suitable. Because sound intensity is measured in decibels (dB), the material removal rate is also logarithmically and multiplied by 10 to convert it to decibels and match the result; this converts fractions into subtraction, resulting in the formula above. Through this method, vibrations between the tool and the material, which cause tool wear, are minimized, and roughing efficiency is maximized by maximizing the volume of material removed per hour. Therefore, the present invention considers the specific cutting noise as an important factor in setting machining conditions and proposes a method to minimize it, thereby achieving stable and efficient machining.

[0033] At this time, if a non-cutting noise amount is applied by adding a weight to the material removal rate decibel as in [Mathematical Formula 1], it is possible to compensate for individual differences among field experts regarding the importance of tool life and machining time. Here, the weight is a factor that increases or decreases the influence of the material removal rate; it can be increased to around 1.0 if productivity is considered important, or lowered to around 0.5 if the reduction of cutting noise is considered important, thereby reflecting the expert's preference.

[0034] In this invention, conditions for feed rate, axial depth of cut, and rotational speed are set based on a newly proposed method for minimizing non-cutting noise. The flowchart for setting machining conditions is shown in Fig. 1 (b). If the feed rate and axial depth are excessively high, abnormal noise may occur in the workpiece or tool; conversely, if they are too low, productivity may decrease. First, the recommended conditions provided by the tool manufacturer are set as the initial machining conditions, and the sound level is measured while increasing or decreasing the feed rate, depth of cut, and rotational speed. If the calculated non-cutting noise decreases, the conditions are changed in the same direction, and if the non-cutting noise increases, they are changed in the opposite direction. By repeating this process using the gradient descent method, the machining condition that minimizes the non-cutting noise is identified and set as the optimal machining condition.

[0035] More specifically, referring to FIG. 1(b), the cutting unit (100) performs cutting under the initial processing conditions, and the measuring unit (200) measures the sound generated during the cutting process and transmits it to the control unit (300). Subsequently, the control unit (300) determines whether the measured value of the measuring unit (200) exceeds a preset value. At this time, if the control unit (300) determines that the measured value of the measuring unit (200) does not exceed the preset value, it sets it as the final processing condition. In addition, if the control unit (300) determines that the measured value of the measuring unit (200) exceeds the preset value, the processing condition is adjusted by varying the feed rate, axial cutting depth, or rotational speed of the tool.

[0036] Here, when the measurement value of the measuring unit (200) exceeds a preset reference value, the control unit (300) can gradually reduce the feed rate of the tool while keeping the axial cutting depth and rotational speed of the tool fixed. Additionally, when the measurement value of the measuring unit (200) exceeds a preset reference value, the control unit (300) can gradually reduce the axial cutting depth of the tool while keeping the feed rate and rotational speed of the tool fixed. Finally, when the measurement value of the measuring unit (200) exceeds a preset reference value, the control unit (300) can gradually reduce the rotational speed of the tool while keeping the feed rate and axial cutting depth of the tool fixed. That is, the control unit (300) can select and preferentially vary any one of the feed rate, axial cutting depth, and rotational speed of the tool depending on the state of the cutting unit (100) or the state of the tool. In addition, the measuring unit (200) continuously measures the noise generated during the cutting process of the cutting unit (100).

[0037] Subsequently, the cutting unit (100) performs cutting processing under the changed processing conditions, and the measuring unit (200) re-measures the sound generated during the cutting process and transmits it to the control unit (300). Here, the control unit (300) determines whether the amount of non-cutting sound derived by [Equation 1] is reduced. Here, if the control unit (300) determines that the derived amount of non-cutting sound is not reduced, it adjusts the processing conditions again. Also, if the control unit (300) determines that the derived amount of non-cutting sound is reduced, the cutting unit (100) performs cutting processing under the changed processing conditions, and the measuring unit (200) re-measures the sound generated during the cutting process. Subsequently, the control unit (300) determines again whether the measured value of the measuring unit (200) exceeds a preset value. At this time, if the control unit (300) determines that the measured value of the measuring unit (200) does not exceed a preset value, it is set as the final processing condition. Additionally, if the control unit (300) determines that the measured value of the measuring unit (200) exceeds a preset value, it returns to the step of adjusting the processing condition again.

[0038] Hereinafter, an experiment to set final processing conditions using the processing condition setting system of the present invention will be described in detail with reference to the attached drawings.

[0039] First, regarding the setting of on-site machining conditions, the tool manufacturer's recommended conditions are average settings established considering machining efficiency and quality. Companies using different machining equipment, tool lengths, material clamping methods, cutting fluids, and machining patterns must set their own machining conditions. Therefore, when machining begins, experienced field experts intuitively and quickly set machining conditions based on noise measurements. Starting from the recommended initial machining conditions, field experts use noise measurements to increase the feed rate, axial depth of cut, and rotational speed to establish stable and highly productive roughing conditions. First, starting at a rotational speed of 1,000 rpm and a depth of 1 mm, the feed rate is gradually increased to 200, 400, 600, 800, and 1,000 mm / min to determine the feed rate based on sound and experience. Second, the axial depth of cut is increased to 1, 2, and 3 mm while listening to the sound to find a stable machining depth. Third, the rotational speed is varied to 1,000, 1,200, and 1,400 rpm to find the condition where the sound is most stable.

[0040] In addition, to verify the relationship between the processing conditions of field experts and the non-cutting sound volume through sound level measurement, the sound volume of all processes is measured using the TES 53H sound meter model. C-frequency weighting suitable for measuring machine sound is applied, and the time weighting is set to Slow to display the average sound volume every second. The above-mentioned cutting section (100) is a machining center installed 20 cm in front of the left door, and the cutting sound and factory background sound volume heard by field experts are similar to the level of the cutting sound and factory background sound heard by field experts. The experiment is conducted with other equipment stopped so as not to be affected by the cutting sound of other equipment, and the factory background noise measured when no cutting is performed is 74 dB.

[0041] In addition, as a method to minimize non-cutting noise, the basic correlation between feed rate, depth of cut, rotational speed, and noise volume is quantified through sound intensity measurement, and the correlation between the newly proposed non-cutting noise and the machining condition setting process of field experts is identified. Furthermore, using a machining condition setting method that minimizes non-cutting noise, the feed rate, axial depth of cut, and rotational speed are determined on inclined surfaces, and the feed rate at which the non-cutting noise is minimized is also determined on flat surfaces at the set rotational speed and depth.

[0042] Furthermore, to evaluate tool wear based on machining time, the entire surface of the product duplex material is machined using machining conditions recommended by the tool manufacturer and those established in this study to assess machining time and tool wear. Video recordings are taken during machining to measure the actual machining time, and flank wear on the side and bottom inserts is measured under a microscope after machining.

[0043] Referring to FIG. 2, when a field expert changes the processing conditions, the sound level measured by the sound meter of the measurement unit (200) is organized into a graph. As a result, the sound level increases as the feed speed and axial depth increase, and under the same conditions, the sound is louder on a flat surface than on an inclined surface. The sound level according to the rotational speed does not show a specific trend.

[0044] More specifically, FIG. 2(a) is a graph of sound volume according to feed rate, where the sound volume, which is the measured value of the measuring unit (200), increases as the feed rate increases. In inclined surface milling with a rotational speed of 1000 rpm and an axial machining depth of 1 mm, as the feed rate increased from 200 mm / min to 1000 mm / min, the sound volume increased by 3.4 dB from 74.7 dB to 78.1 dB. In flat milling with a rotational speed of 1200 rpm and an axial depth of 2 mm, as the feed rate increased from 200 mm / min to 800 mm / min, the sound volume increased by 6 dB from 78.6 dB to 84.6 dB. FIG. 2(b) is a graph of sound volume according to the inclined surface machining depth. As the axial machining depth increased from 1 mm to 3 mm, the sound volume increased from 77 dB to 84 dB, and the sound volume increased by 3 dB and 4 dB, respectively, for every 1 mm increase in depth. Figure 2(c) is a graph of sound volume according to rotational speed. When the rotational speed changed from 1000 rpm to 1400 rpm, the sound volume changed very slowly. In Figure 2(a), at the same rotational speed of 1200 rpm and depth of 2 mm, the sound volume in planar machining was approximately 4.2 dB higher than in inclined plane machining. In Figure 2(c), at a feed rate of 800 mm / min, an axial depth of 2 mm, and rotational speeds of 1200 rpm and 1400 rpm, the sound volume of planar milling was found to be 4.2 dB higher than that of inclined plane milling. No correlation was found between the feed rate of 600 mm / rev, an axial depth of 2 mm, and a rotational speed of 1200 rpm selected by field experts and the sound volume. This suggests that field experts consider other factors in addition to sound volume when setting machining conditions.

[0045] Referring to FIG. 3, when a field expert changes the processing conditions, the non-cutting sound volume calculated by subtracting the decibel value of the material removal rate, which is a measure of roughing productivity, from the sound level measured by the sound meter of the measurement unit (200) is organized into a graph. As a result, it can be confirmed that the processing conditions set by the field expert through hearing and experience match the process of minimizing the non-cutting sound volume. This means that the process of a field expert setting processing conditions through hearing can be simulated by artificial intelligence as a process of minimizing the non-cutting sound volume.

[0046] More specifically, the blue S1000 d1 slope graph in FIG. 3 (a) represents the difference between the sound level measured by the sound meter of the measurement unit (200) and the material removal rate decibels when a field expert sets conditions by auditory means while milling an inclined surface at a rotational speed of 1000 rpm and a depth of 1 mm, while increasing the feed rate from 200 mm / min to 1000 mm / min at equal intervals. As the feed rate increases, the amount of non-cutting noise decreases until it reaches a minimum value at 800 mm / min, and then increases again when the feed rate is increased. The feed rate for the inclined surface milling of 800 mm / min derived by the field expert using the sound meter of the measurement unit (200) matches the feed rate that minimizes the amount of non-cutting noise. The non-cutting noise level was reduced by 3.7dB to 48.0dB at the condition of 800 mm / min, which was derived by a field expert using the sound meter of the measurement unit (200), compared to 51.7dB at the condition of 200 mm / min recommended by the tool manufacturer. It can be seen that there is a high correlation between the field expert's feed rate setting and the process of minimizing the non-cutting noise level in inclined surface milling.

[0047] Figure 3(b) is a graph showing the difference between the sound level and the material removal rate measured during the process of increasing the axial machining depth to 1, 2, and 3 mm at a feed rate of 800 mm / min set by a field expert. Since the depth derived by the expert using the sound meter of the measurement unit (200) matches the depth of 2 mm, where the non-cutting sound amount is minimized to 4.79 dB, it can be seen that there is a high correlation between the process of setting the axial depth of the inclined surface and the process of minimizing the non-cutting sound amount.

[0048] Figure 3(c) is a graph showing the difference in sound level and material removal rate in decibels for the process of selecting the optimal rotational speed by varying the rotational speed to 1000, 1200, and 1400 rpm at a feed rate of 800 mm / min and a depth of 2 mm selected by an expert. The non-cutting noise level was smallest at 47.8 dB at the rotational speed selected by the expert using the sound meter of the measuring unit (200) at 1200 rpm. Thus, the process of a field expert selecting the feed rate, depth, and rotational speed through the sound meter of the measuring unit (200) in inclined surface milling can be described as a process of minimizing the non-cutting noise level.

[0049] When milling a flat surface on an inclined plane under conditions of a selected rotational speed of 1200 rpm, a depth of 2 mm, and a feed rate of 800 mm / min, the sound was abnormally loud, so an expert reduced the feed rate to 600, 400, and 200 mm / min and re-selected the feed rate through the sound meter of the measuring unit (200). The difference in decibels between the measured sound level and the material removal rate during this process is shown as the orange square S1200 d2 flat graph in Fig. 3 (a), and in flat surface machining, the non-cutting sound was smallest at a feed rate of 400 mm / min at 51.5 dB. Considering both the inclined plane and the flat surface, the field expert selected 600 mm / min as the final feed rate.

[0050] The process of a field expert selecting machining conditions using the sound meter of the measurement unit (200) above corresponds to the process of minimizing non-cutting noise. The difference is that while the field expert selected the same feed rate of 600 mm / min for both the inclined surface and the flat surface, the method for minimizing non-cutting noise recommends a feed rate of 800 mm / min for the inclined surface and 400 mm / min for the flat surface. The rotational speed is 1200 rpm and the axial depth is 2 mm, and the feed rate is 200 mm / min as recommended by the tool manufacturer and 600 mm / min as set by the field expert, while the conditions for minimizing non-cutting noise are 800 mm / min for the inclined surface and 400 mm / min for the flat surface.

[0051] Accordingly, to compare the machining time and the wear of the above tools, tool wear is compared by machining duplex material under the tool manufacturer's recommended condition of 200 mm / min, the field expert's set condition of 600 mm / min, the non-cutting noise minimization condition of 800 mm / min for the rake face, and 400 mm / min for the flat surface. In all three experiments, the conditions of rotational speed of 1200 rpm, axial depth of 2 mm, and path gap of 1 mm are identical.

[0052] When machining was performed at TaeguTec’s recommended feed rate of 200 mm / min, the machining time was long at 124 minutes, but the tool wear was 0.11 and 0.13 mm, indicating that abrasive wear occurred minimally. This means that when you want to extend tool life even if duplex machining takes a long time, it is appropriate to reduce the feed rate per revolution to 0.17 mm / rev or less to generate thin chips.

[0053] When machining was performed at a feed rate of 600 mm / min, as set by the expert's hearing, the machining time was short at approximately 41 minutes, but tool wear was high at 0.51 and 0.28 mm. Chipping occurred in more than five locations on the side inserts, and chipping occurred on the bottom inserts at the same locations where the most severe chipping occurred on the side inserts. Although the machining conditions set by the field expert's hearing increased productivity threefold, tool life was significantly shortened, so it was not an optimal condition in terms of man-hours. Increasing the duplex machining feed rate to 0.2 mm / rev reduced the machining time by about one-third, but the increased chip thickness increased the force applied to the cutting edge, causing insert chipping.

[0054] As a result of machining at 800 mm / min for the inclined surface and 400 mm / min for the recommended conditions of the method for minimizing non-cutting noise of the present invention, the machining time was short at 43 minutes and the tool wear was large at 0.77 and 0.09 mm. Chipping occurred in more than 4 places with the side insert, and only fine grinding wear occurred with the bottom insert without chipping.

[0055] When comparing tool wear by machining duplex material under conditions of tool manufacturer, field expert, and minimizing non-cutting noise, it was found that while the field expert and minimizing non-cutting noise conditions increased productivity by approximately three times compared to the manufacturer's conditions, tool wear increased significantly. This indicates that the minimizing non-cutting noise method showed results similar to the field expert method.

[0056] Consequently, the machining condition setting system of the present invention has the advantage of maximizing the efficiency of machining by measuring the sound generated during cutting, measuring the sound changes while modifying machining conditions such as the tool feed rate, cutting depth, and rotational speed, deriving the material removal rate and non-cutting sound volume from the measured sound, and setting machining conditions in a direction that reduces the non-cutting sound volume by verifying a mathematical formula for the non-cutting sound volume, thereby minimizing vibrations between the tool and the material that cause tool wear and maximizing the volume of material removed per hour.

[0057] As such, those skilled in the art to which the present invention pertains will understand that the technical configuration of the present invention described above can be implemented in other specific forms without altering the technical concept or essential features of the present invention.

[0058] Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting, and the scope of the invention is defined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the invention.

[0059] In this invention, the roughing of duplex stainless steel, which is being encountered for the first time by an expert who has set milling conditions based on cutting sounds in the field for 20 years, was selected as the subject of the machining condition setting process. The machining condition setting process was investigated to determine if it was numerically meaningful by measuring the cutting sound level with a noise meter. The correlation between the field expert's machining condition setting process and the process of minimizing the ratio of sound level to material removal rate was identified. Duplex was machined using the tool manufacturer's recommended conditions, the field expert's set conditions, and the ratio minimization conditions proposed in this invention, respectively, and the flank wear of the ball end mill insert was compared.

[0060] This invention verifies the mathematical validity of the process of setting processing conditions based on on-site auditory perception by measuring sound, and models this process to enable computer simulation. Specifically, it measures and quantifies sound signals during the process of setting processing conditions based on the recommended conditions of a TaeguTec ball end mill, targeting duplex materials being processed for the first time by an on-site expert. It also identifies a new formula and correlation utilizing the relationship between sound intensity and Material Removal Rate (MRR). This distinguishes the invention from existing ones by presenting the possibility of rapid processing condition setting through sound-based monitoring. By mathematically modeling the process of experts setting processing conditions at the manufacturing site, the results of this invention can provide practical assistance in realizing smart factories where artificial intelligence will be responsible for selecting processing conditions. Explanation of the symbols

[0061] 100 : Cutting section 200 : Measurement section 300 : Control unit

Claims

Claim 1 A machining condition setting system comprising: a cutting unit equipped with a tool on one side; a measuring unit for measuring sound generated during cutting in the cutting unit; and a control unit for receiving and analyzing the measured value from the measuring unit and controlling the cutting unit; wherein the control unit derives the non-cutting sound amount based on the measured value from the measuring unit and the following [Equation 1], and if the measured value from the measuring unit exceeds a preset reference value, changes the machining conditions by varying the feed rate, axial cutting depth, or rotational speed of the tool, the cutting unit performs cutting under the changed machining conditions, the measuring unit re-measures the sound generated during cutting and transmits it to the control unit, and the control unit derives the non-cutting sound amount again based on the re-measured value from the measuring unit and determines the optimal machining conditions based on the increase or decrease in the non-cutting sound amount. [Equation 1] Non-cutting sound amount = Measured value from the measuring unit (dB) - Weight × 10log(MMR), MMR = Material Removal Rate, Weight = Weight Claim 2 A machining condition setting system according to claim 1, wherein the control unit, when the measured value of the measuring unit exceeds a preset reference value, gradually reduces the feed rate of the tool while keeping the axial cutting depth and rotational speed of the tool fixed. Claim 3 A machining condition setting system according to claim 1, wherein the control unit, when the measured value of the measuring unit exceeds a preset reference value, gradually reduces the axial cutting depth of the tool while keeping the feed speed and rotational speed of the tool fixed. Claim 4 A machining condition setting system according to claim 1, wherein the control unit, when the measured value of the measuring unit exceeds a preset reference value, gradually reduces the rotational speed of the tool while keeping the feed speed and axial cutting depth of the tool fixed. Claim 5 delete

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