Journal articles: 'Cutting defects'

1

Hou, Ning, Li Zhou, Shu Tao Huang, and Li Fu Xu. "Finite Element and Experimental Analysis of Edge Defects Formation during Orthogonal Cutting of SiCp/Al Composites." Advanced Materials Research 500 (April 2012): 146–51. http://dx.doi.org/10.4028/www.scientific.net/amr.500.146.

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In this paper, a finite element method was used to dynamically simulate the process of the edge defects formation during orthogonal cutting SiCp/Al composites. The influence of the cutting speed, cutting depth and rake angle of the PCD insert on the size of the edge defects have been investigated by using scanning electron. According to the simulated results, it can be provided that the cutting layer material has an effect on transfer stress and hinder the chip formation in the critical transition stage, and the critical transition point and distance are defined in this stage. The negative shear phenomenon is found when the chip transit to the edge defects in the flexure deformation stage, so the process of the chip formation is the basis of the edge defects formation. In addition, the relationship between the nucleation and propagation direction of the crack and the variation of the edge defect shape on the workpiece was investigated by theory, and it found that the negative shear angle formation is the primary cause of the edge defect formation. A mixed mode crack is found in the crack propagation stage. The sizes of edge defects were measured by the experiment and simulation, and the edge defect size decrease with the increasing of tool rake angle, while increase with increasing cutting depth and cutting speed.

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Zou, Chang Bin, Chuan Zhen Huang, Bin Zou, Yu Huan Fei, Han Lian Liu, Hong Tao Zhu, and Jun Wang. "Establishment of the Low Defect Ceramic Cutting Tool Database." Key Engineering Materials 589-590 (October 2013): 357–60. http://dx.doi.org/10.4028/www.scientific.net/kem.589-590.357.

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This paper analyzes the reasons of the defects generation of the ceramic cutting tool materials. The defects in the ceramic cutting tool materials are caused by chemical compatibility and physical mismatch during the designing process, and caused by grain abnormal growth and sintering parameters during the preparation stage. The database of low defect ceramic cutting tool is established and the data structure of the database is described. The users can use the database to design the tool material system through the mode that can reduce the defects.

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Lu, Ji Li, and Ming Xing Lin. "A Cutting Line Positioning and Defects Detection System for Polyurethane Plate Based on Computer Vision." Advanced Materials Research 562-564 (August 2012): 119–22. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.119.

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In this paper, we present a design of a real-time computer vision system for polyurethane plate cutting line positioning and defects detection. The main defect of polyurethane plate is uneven texture which doesn’t meet the product requirements. We translate the original image to gray image and find the points with strongest gray as the cutting line, extract feathers and detect defects. The experimental results show that it is easy and effective to position cutting points and find defects of polyurethane plate, which can meet the requirements of production and has great practical value.

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4

Kondo, Yasuo, Yuki Doi, Takafumi Adachi, Satoshi Sakamoto, Kenji Yamaguchi, Tsuyoshi Fujita, and Mitsugu Yamaguchi. "Proposal of Constant Load Feeding Method as a High Precision Cutting Tool for CFRP." Advanced Materials Research 1136 (January 2016): 209–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1136.209.

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An innovative cutting method, constant load feeding method, is proposed as a high precision secondary working tool in CFRP cutting. The constant load feeding can restrain the occurrence of cutting defects such as burr and scuffing in a diamond saw cutting. The combining of constant load feeding with point contact eliminated most of the cutting defects even in the CFRP cutting with a low rigidity cutting tool like the diamond saw blade. In addition, there was no apparent cutting damage on the cutting surface obtained from the drilling with constant load feeding. These facts indicate that the self-generated feed rate in the constant load feeding would be the optimal feed rate to realize a defect-free drilling of CFRP composites.

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Twisselmann, U. "Cutting rectangles avoiding rectangular defects." Applied Mathematics Letters 12, no. 6 (August 1999): 135–38. http://dx.doi.org/10.1016/s0893-9659(99)00092-0.

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6

Zou, De Jin, Shu Tao Huang, Li Zhou, Li Fu Xu, Ning Hou, and Jing Lei Wang. "Experimental Study on Exit Edge Defects in Two Dimension Cutting of SiCp/Al Composites." Materials Science Forum 723 (June 2012): 326–31. http://dx.doi.org/10.4028/www.scientific.net/msf.723.326.

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In this paper, the influence of the tool rake angle, cutting depth and cutting speed on exit edge defect sizes are discussed by the two dimension cutting experiment of SiCp/Al composites. The sizes are measured by using the Keyence VHX-1000C type super preview 3D microscopy. The results indicate that exit edge defect sizes are influenced greatly by tool rake angle and cutting depth, and are influenced slightly by the cutting speed. The edge defect sizes have an overall downward trend when the tool rake angle is smaller than 5°, and have an apparent upward trend when the tool rake angle (γ0) is 10°.The length (L), height (H) of exit edge defects and the negative shear angle increase with increasing of the cutting depth.

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Zeng, Chao, Chunqing Wang, Yanhong Tian, Chunjin Hang, Wei Liu, and Rong An. "Characterization of the Hot-Cutting Defect Generated from Shape Machining of Alumina Green Tape in the Ceramic-Package Manufacturing Process." Journal of Microelectronics and Electronic Packaging 12, no. 1 (January 1, 2015): 55–60. http://dx.doi.org/10.4071/imaps.433.

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This paper characterizes the rarely mentioned but very damaging defects formed during the hot-cutting process of alumina green tape. Surface and edge morphologies of the hot-cutting surface and a natural surface were examined by optical microscope and scanning electron microscope before and after the sintering process. Obviously different from the natural surface, the hot-cutting surface had a transverse crack-like defect scattered over the surface and a tearing, notch-like defect on the lower edge. A 31 × 22 full factorial experiment was conducted to evaluate the flexural strength controlled by the hot-cutting defect and inherent defects in ceramics. Variance analysis revealed a significant interaction between surface and wearing. The wearing factor had a statistically significant impact on the fracture strength of the top surface but not that of the side and bottom surfaces.

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Zhou, Xiang, Yi, Gao, and Xie. "Experimental and Numerical Study of Edge Defects When Turning 17vol.% SiCp/2009Al Composites." Applied Sciences 9, no. 18 (September 11, 2019): 3817. http://dx.doi.org/10.3390/app9183817.

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In this work, a three-dimensional large-deformation thermo-elastic-plastic finite element model for oblique cutting was established to analyze edge defects during the machining of 17vol.% SiCp/2009Al composites. The formation process of edge defects at the workpiece exit during turning was investigated, and the influence of depth of cut, feed rate, and spindle speed on the edge defect sizes at the workpiece exit was explored. The results show that a negative deformation plane began to form as the cutting tool approached the exit end of cut, and the resultant cracks propagated towards the negative shear deformation plane, which led to workpiece edge defects. In addition, the size of edge defects increased with increasing depth of cut and feed rate, while the spindle speed had less influence on the size of edge defects. The numerical results of the effects of cutting parameters on edge defects were also compared to those of the turning experimental data, and were found to be in reasonable agreement.

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Zhang, Shuo, and Wenjun Zong. "Micro Defects on Diamond Tool Cutting Edge Affecting the Ductile-Mode Machining of KDP Crystal." Micromachines 11, no. 12 (December 14, 2020): 1102. http://dx.doi.org/10.3390/mi11121102.

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As a soft-brittle material, the machined surface quality of potassium dihydrogen phosphate (KDP) crystal is heavily affected by the edge quality of the diamond cutting tool. However, nanoscale micro defects inevitably occur on the freshly sharpened tool edge, and the machining mechanism for KDP crystal remains unclear. Therefore, in this work, three types of tool-edge micro defects are classified according to their cross-sections, including the blunt-edge, crescent-edge, and flat-edge micro defects. Moreover, the smoothed particle hydrodynamics (SPH) method is employed to reveal the material removal mechanism of KDP crystal with consideration of different tool-edge micro defects, and the flat-edge micro defects are subdivided into flat edge A (similar to flank wear) and flat edge B (similar to chamfered edge) on the basis of their effects in machining. The simulation results indicate that the surfaces machined by crescent edge and flat edge A are unsmooth with large-size defects due to the disappearance of hydrostatic pressure beneath the cutting edge. As for the blunt edge and flat edge B, the machined surfaces are smooth with a favorable increment of hydrostatic pressure for processing brittle materials, which indicates that a solution to eliminate the tool-edge micro defects is necessary, e.g., the passivation method. For keeping the cutting edge as sharp as possible in removing the tool-edge micro defects completely by passivation, the effect of tool shank depression angles on the geometries of the passivated cutting edge is investigated, and a high-quality cutting edge with a micro chamfered edge is obtained after passivation at a depression angle of 60° and re-sharpening of the rake face. Finally, the tool cutting performance after passivation is validated through fly-cutting experiments of KDP crystal. The chamfered edge can produce the best defect-free surface with the minimum surface roughness.

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10

Phophoung, Aphichad, and Viboon Tangwarodomnukun. "Defect Reduction in the CO₂ Laser Cutting of Glassware Rim." Materials Science Forum 872 (September 2016): 133–37. http://dx.doi.org/10.4028/www.scientific.net/msf.872.133.

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Defects in glassware are unacceptable in terms of product strength and aesthetics. The unsmooth cut rim of glassware can often be found in the laser trimming of excessive part after blow molding process. Such defect is basically not safe to use and has to be rejected from the production, thereby inevitably increasing the manufacturing cost and time. Hence, this research aims to reduce the defect in glassware rim induced by the laser cutting process. A wine glass was used as a workpiece sample in this study. Laser power, laser cutting time and workpiece rotational speed were tested and optimized to reduce the defects by using the response surface methodology. The optimum condition for the laser cutting of wine glass was found to be 225-W laser power, 2.4-s cutting duration and 335-rpm rotational speed.

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Qin, Zhongcheng, Tan Li, Qinghai Li, Guangbo Chen, and Bin Cao. "Combined Early Warning Method for Rock Burst and Its Engineering Application." Advances in Civil Engineering 2019 (January 27, 2019): 1–10. http://dx.doi.org/10.1155/2019/1269537.

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Rock burst is a common mine disaster often accompanied with casualties and property damage. In order to effectively predict and prevent the rock burst occurrence, an effective and accurate method for predicting rock burst is necessary. This paper first establishes the relationship between the drilling cuttings and the releasable elastic deformation energy. However, the traditional drilling cutting method has the defect that the drilling depth cannot reach the stress concentration area and the drilling cuttings cannot accurately reflect the internal stress variation in the deep part of coal body. So, an improved drill cutting method is presented to make up for these defects. Finally, the combined monitoring method based on the improved drilling cutting method and the microseismic monitoring method is established. It not only overcomes the limitations of a single prediction method but also effectively utilizes the advantages of improved drilling cutting method and the microseismic monitoring method. And this combined monitoring method is applied to the No. 3302 coalface of Xingcun Coal Mine. The obtained results indicate that the combined monitoring method can improve the prediction capabilities of the rock burst and provide novel insights for preventing the rock burst occurrence.

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12

Ciecieląg, Krzysztof, Krzysztof Kecik, and Kazimierz Zaleski. "Defects detection from time series of cutting force in composite milling process by recurrence analysis." Journal of Reinforced Plastics and Composites 39, no. 23-24 (June 20, 2020): 890–901. http://dx.doi.org/10.1177/0731684420935985.

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The article presents possibility of defects detection from milling time series using nonlinear methods: recurrence plots and recurrence quantifications. The defects are modeled as the holes with different diameters and depths. This allows estimation of the minimal size of defect possible to detect. Based on the conducted research, it has been shown that some of the recurrence indicators enable detection of defects. These recurrence indicators have been tested on the reals damage. Additionally, we show influence of the defect depth on the recurrence indicator values.

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13

Hairiyah, Nina. "PENERAPAN SIX SIGMA DAN KAIZEN UNTUK MEMPERBAIKI KUALITAS ROTI DI UD. CJ BAKERY[Application of six sigma and kaizen to improve the bread quality In UD. CJ Bakery]." Jurnal Teknologi & Industri Hasil Pertanian 25, no. 1 (April 1, 2020): 35. http://dx.doi.org/10.23960/jtihp.v25i1.35-43.

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Sweet bread produced by UD. CJ Bakery has defects in the form of size, texture and color. In this study the process of improving the quality of sweet bread in UD. CJ Bakery was done by application of the six sigma and kaizen methods. The results showed that the cause of bread size defects was a less efficient cutting technique with a defect percentage of 28.97%. Color defects were caused by the length of the curing process and too high heating temperature with a defect percentage value of 20.51%, while texture defects were caused by a prolonged proofing process with a defect percentage value of 50.51%. Actions to reduce the value of product size, color and texture defects were by using good and correct cutting techniques, taking into account the time and temperature of the oven, and making a simple proofing cabinet. The sigma level before the improvement was 2.24 with a DPMO value of 259,333. After improvement, the sigma level value was 2.38 and the DPMO value was 115,600. These results showed that UD. CJ Bakery has improved its quality after implementing Six Sigma and Kaizen.

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14

Yin, Aihua, Chong Chen, Dongping Hu, Jianghai Huang, and Fan Yang. "An improved heuristic-dynamic programming algorithm for rectangular cutting problem." Computer Science and Information Systems 17, no. 3 (2020): 717–35. http://dx.doi.org/10.2298/csis200125017y.

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In this paper, the two-dimensional cutting problem with defects is discussed. The objective is to cut some rectangles in a given shape and direction without overlapping the defects from the rectangular plate and maximize some profit associated. An Improved Heuristic-Dynamic Program (IHDP) is presented to solve the problem. In this algorithm, the discrete set contains not only the solution of one-dimensional knapsack problem with small rectangular block width and height, but also the cutting positions of one unit outside four boundaries of each defect. In addition, the denormalization recursive method is used to further decompose the sub problem with defects. The algorithm computes thousands of typical instances. The computational experimental results show that IHDP obtains most of the optimal solution of these instances, and its computation time is less than that of the latest literature algorithms.

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Haddad, Madjid, Redouane Zitoune, Florent Eyma, and Bruno Castanié. "Influence of Tool Geometry and Machining Parameters on the Surface Quality and the Effect of Surface Quality on Compressive Strength of Carbon Fibre Reinforced Plastic." Materials Science Forum 763 (July 2013): 107–25. http://dx.doi.org/10.4028/www.scientific.net/msf.763.107.

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In this chapter the influence of tool geometry and cutting conditions on cutting forces, surface defects and the percetage of dust generated durring trimming and reaching the pulmonary alveoli is investigated. The surface defects were analysed using a scanning electron microscope and diferent surface roughness measurement devices. It was observed that these leters were highly depend on the cutting condition and the tool geometry, and more important that the effect of cutting parameters can be completely diferent from a tool to an other or even when considering different ranges of cutting parameters (standard cutting speed and high cutting speed). The compressive strenght after machining is also investigated. It is observed that whatever tool geometry, cutting conditions, surface roughnesses (defects) are, the response still the same for all the composite samples except for those machined at cutting temperatures higher than the glass fiber transition.

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16

Liu, Ying, Yan Tao Zhu, Feng Ming Xia, and Zhao Jun Xu. "Research on the Intelligent Manufacturing System for Lumber Cutting." Advanced Materials Research 631-632 (January 2013): 1441–44. http://dx.doi.org/10.4028/www.scientific.net/amr.631-632.1441.

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To enhance the rate of lumber cutting output and save the production cost, a new intelligent manufacture system is developed. Considering the requirements of wood surface defects detection and optimal layout, the overall structure is established. The system has six function modules, there are cutting task module, laser scanning images processing module, defects identify module, optimal layout module, machining plan module and data manage module. According to laser scanning, images processing and defects identify programs help manufacturer to get profile data, acquire profile image, extract features, and identify lumber defects. Optimal layout module gives an intelligent program to decide the maximum number of cutting board pieces and shows operator the visualized layout. Two examples are shown which apply algorithms to obtain the optimal layouts for lumber cutting. The intelligent manufacturing system helps people detect lumber defects, make the optimal machining plan and cutting material online quickly.

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17

Wang, Yang Jun, Ming Qiang Pan, Tao Chen, and Li Guo Chen. "The Forming Mechanism of Surface Defects on Machined Surface in High-Speed Cutting of SiCp/Al Composites." Key Engineering Materials 579-580 (September 2013): 171–76. http://dx.doi.org/10.4028/www.scientific.net/kem.579-580.171.

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For investigating the machined surface defects in high-speed cutting of SiCp/Al composites. The simulation and experiment of high-speed cutting process is done. The simulation of high-speed cutting process using the Cowper-Symonds model is established to explore the forming mechanism of the machined surface defects. The results show that the machined surface defects include small pit, big pit, groove and the raised particle. The experiment which uses the same cutting parameters with the simulation of FEM (Finite Element Method) model is carried out to verify the results of FEM simulation. The results indicate that the forming mechanism of machined surface defects prove to be true.

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Viswanath, M. "Detection of Defects in Polypropylene Fabric and Synchronized Cutting with Cutting Machine." Computer-Aided Design and Applications 8, PACE (December 1, 2011): 15–30. http://dx.doi.org/10.3722/cadaps.2011.pace.15-30.

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Li, Xiaojun, Zhanqiang Liu, and Xiaoliang Liang. "Tool Wear, Surface Topography, and Multi-Objective Optimization of Cutting Parameters during Machining AISI 304 Austenitic Stainless Steel Flange." Metals 9, no. 9 (September 3, 2019): 972. http://dx.doi.org/10.3390/met9090972.

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The application of AISI 304 austenitic stainless steel in various industrial fields has been greatly increased, but poor machinability classifies AISI 304 as a difficult-to-cut material. This study investigated the tool wear, surface topography, and optimization of cutting parameters during the machining of an AISI 304 flange component. The machining features of the AISI 304 flange included both cylindrical and end-face surfaces. Experimental results indicated that an increased cutting speed or feed aggravated tool wear and affected the machined surface roughness and surface defects simultaneously. The generation and distribution of surface defects was random. Tearing surface was the major defect in cylinder turning, while side flow was more severe in face turning. The response surface method (RSM) was applied to explore the influence of cutting parameters (e.g., cutting speed, feed, and depth of cut) on surface roughness, material removal rate (MRR), and specific cutting energy (SCE). The quadratic model of each response variable was proposed by analyzing the experimental data. The optimization of the cutting parameters was performed with a surface roughness less than the required value, the maximum MRR, and the minimum SCE as the objective. It was found that the desirable cutting parameters were v = 120 m/min, f = 0.18 mm/rev, and ap = 0.42 mm for the AISI 304 flange to be machined.

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Gaar, N. P., A. Kh Rakhimyanov, and A. A. Loktionov. "PREVENTION OF CUTTING DEFECTS BY OPTIMIZING THE TRAJECTORY FOR HIGH-PRECISION PLASMA CUTTING." Vestnik of Kuzbass State Technical University 18, no. 2 (2018): 70–75. http://dx.doi.org/10.26730/1999-4125-2018-2-70-75.

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21

Ciecieląg, K., K. Kęcik, and K. Zaleski. "Effect of Depth Surface Defects in Carbon Fibre Reinforced Composite Material on the Selected Recurrence Quantifications." Advances in Materials Science 20, no. 2 (June 1, 2020): 71–80. http://dx.doi.org/10.2478/adms-2020-0011.

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AbstractThe paper discusses the problem of possibility of the detecting surface defects in carbon fibre reinforced plastics (CFRP) materials on the basis of the milling time series. First, the special defects in the hole-shaped with various depth were made. Next, the cutting forces are measured during the milling machining. Finally, the recurrence plot and quantification analysis was applied. The obtained results show that the depth defect influences the selected recurrence quantifications, which can be used as the simple defect indicators. The conducted research allow to determine the percentage share of the detectable defects. The novelty of the work and an unresolved problem is the selection of recurrence quantifications with the simultaneous use of them to detect the size of defects in carbon fibre reinforced plastics.

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Chen, Jia Xuan, Ying Chun Liang, Xia Yu, Zhi Guo Wang, and Zhen Tong. "Deformation Mechanism of Diamond Nanocutting Single-Crystal Copper Using Molecular Dynamics Simulatio." Advanced Materials Research 239-242 (May 2011): 2775–78. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.2775.

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To study the removal mechanism of materials during nano cutting, molecular dynamics method is adopted to simulate single crystal copper nanomachining processes, and subsurface defects evolvements and chip forming regulation are analyzed by revised centro-symmetry parameter method and the ratios of the tangential cutting forceand the normal cutting force. The results show that there are different defects under different cutting depths. When cutting depths is shallower, there are dislocation loop nucleation in the subsurface of the workpiece beneath the tool; however, when the cutting depths is deeper, there are dislocations nucleation and slipping along {101} plane and (111) plane. In addition, both tangential cutting forceand the normal cutting force decrease as the cutting depths decreasing. When the ratios of the normal cutting force and the tangential cutting force is below 0.9, the chip will be formed.

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Li, Xiaoyu, Liangbao Jiang, Minbo Wang, Jiaxi Liu, Jiaming Li, and Yue Yan. "The influence of different cutting parameters on the glass edge quality." E3S Web of Conferences 213 (2020): 03011. http://dx.doi.org/10.1051/e3sconf/202021303011.

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The influence of different cutting parameters on the glass edge quality was investigated, including the cutter material, the sharpening angle of the cutting roll, the cutting speed and the load applied to the roll. The results show that there are less defects on the edge of the glass cut by diamond cutter. There is no obvious influence of cutting speed on the glass edge quality. The cutter with a smaller sharpening angle is more applicable for the cutting of thin glass, and the thick glass is more suitable to use a bigger sharpening angle cutter. Higher cutting load is helpful for the breaking of the glass along the cutting line. However, it may cause more defects on the edge and the surface of the glass.

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Zhu, Ying, Shun He Qi, Zhi Xiang, and Ling Ling Xie. "The Nano-Cutting Mechanism Research of Polysilicon Based on Molecular Dynamics." Advanced Materials Research 690-693 (May 2013): 2559–62. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.2559.

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Molecular dynamics model of the polysilicon material under the micro/nanoscale is established by using molecular dynamics method, make variety of the typical defects distribute to the polysilicon model reasonable and relax the simulation model, obtain the system potential energy curves in the relaxation process and the atomic location figure after the relaxation. Conduct molecular dynamics simulation of nanometric cutting process relying on the development of simulation program, get instant atom position image and draw the cutting force curve. Discusses the typical defects impact on the polycrystalline silicon nanometric cutting process, those mainly include cutting force changes in the cutting process, potential energy changes and processed surface quality etc.

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Liu, Yunan, Shutao Huang, Keru Jiao, and Lifu Xu. "Experimental study on cutting parameters and machining paths of SiCp/Al composite thin-walled workpieces." Advanced Composites Letters 29 (January 1, 2020): 2633366X2094252. http://dx.doi.org/10.1177/2633366x20942529.

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Thin-walled workpieces of silicon carbide particle-reinforced aluminum matrix (SiCp/Al) composites with outstanding properties have been widely applied in many fields, such as automobile, weapons, and aerospace. However, the thin-walled workpieces exhibit poor rigidity, large yield ratio, and easily deform under the cutting force and cutting heat during the machining process. Herein, in order to improve the processing efficiency and precision of higher volume fraction SiCp/Al composite thin-walled workpieces, the influence of different high-speed milling parameters and machining paths on the edge defects is analyzed. The results reveal that the cutting force initially increased and then decreased with the cutting speed. Besides, the cutting force steadily increased with radial cutting depth and feed per tooth, but the influence of feed per tooth is less than radial cutting depth. After up-milling cut-in and cut-out processing and down-milling cut-out processing, the cut-in end of the workpiece exhibited higher breakage and obvious edge defects. However, the workpiece edges remained intact after down-milling cut-in processing. In conclusion, a higher cutting speed, a smaller radial cutting depth, and moderate feed per tooth are required to decrease the cutting force during the milling of SiCp/Al composite thin-walled workpiece. Furthermore, down-milling cut-in processing mode can reduce the edge defects and improve the processing efficiency and precision of the workpiece.

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Masrofah, Isma, and Hariswan Firdaus. "Analisis Cacat Produk Baju Muslim Di Pd. Yarico Collection Menggunakan Metode Failure Mode And Effect Analysis." Jurnal Media Teknik dan Sistem Industri 2, no. 2 (October 17, 2018): 43. http://dx.doi.org/10.35194/jmtsi.v2i2.404.

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Abstract—Yarico Collection Trad. Co. is a company engaged in clothing convection for the last 12 years. One of the problems faced by this company is the number of defective products that exceed the defect tolerance limits set by the company. The company sets a defect limit of 1% of the total production, while in the field the number of defects is 3%. This study aims to find out the priorities of the causes of disability and find out how to reduce the number of defects related to women's Muslim clothing that occur in the cutting process of 20 units from 1250 units, the process of sewing or unifying clothes by 22 units out of 1250 units, the process of closing down 19 units out of 1250 unit, and the pressing process is 14 units out of 1250 units. The researcher used the Failure Mode Effects Analysis (FMEA) method to obtain the most dominant failure mode of production process, the calculation of Risk Priority Number (RPN) generated in the pressing process with RPN 504 value, sewing process with RPN 448 value, the process of stitching stitches with RPN value 392, and the cutting process with the RPN value 384. From the results of the study obtained several proposals according to the highest RPN value to reduce the number of product defects, including: for cutting defects by adding lighting and periodic machine maintenance, for sewing defects scheduled and the use of components that are standard, for defects in obras are made machine maintenance scheduling, the use of spare parts that are standardized, and using a strongbranded needle, for defects in the pressing process by doing good engine maintenance and providing training to workers with use temperature machine according to the type of fabric. Keywords ; product defect, quality improvement, FMEA, RPN Abstrak— PD. Yarico Collection merupakan perusahaan yang bergerak dalam bidang konveksi pakaian selama 12 tahun terakhir. Salah satu permasalahan yang dihadapi oleh perusahaan ini yaitu jumlah produk cacat yang melebihi batas tolerasi cacat yang di tetapkan oleh perusahaan. Perusahaan menetapkan batas cacat yaitu 1 % dari jumlah peroduksi sedangkan dilapangan jumlah cacat sebesar 3 %. Penelitian bertujuan untuk mengatehaui prioritas penyebab cacat dan mengetahui bagaimana cara menurunkan jumlah cacat terkait baju muslim wanita yang terjadi pada proses cutting sebesar 20 unit dari 1250 unit, proses penjahitan atau penyatuan baju sebesar 22 unit dari 1250 unit, proses obras sebesar 19 unit dari 1250 unit, dan pada proses pressing sebesar 14 unit dari 1250 unit. Peneliti menggunakan metode Failure Modes Efect Analysis (FMEA) sehingga didapat mode kegagalan paling dominan diproses produksi, hasil perhitungan Risk Priority Number (RPN) yang dihasilkan pada proses pressing dengan nilai RPN 504, proses penjahitan dengan nilai RPN 448, proses obras jahitan dengan nilai RPN 392, dan pada proses cutting dengan nilai RPN 384. Dari hasil penelitian didapat beberapa usulan sesuai nilai RPN tertinggi untuk menurunkan jumlah cacat produk, diantaranya : untuk cacat cutting dengan melakukan penambahan penerangan serta melakukan perawatan mesin secara berkala, untuk cacat penjahitan melakukan perawatan mesin secara terjadwal serta penggunaan komponen yang sesuai standard, untuk cacat pada obras dibuat penjadwalan perawatan mesin, penggunaan spare part yang sesuai standar, dan menggunakan jarum obras yeng berbahan kuat, untuk cacat pada proses pressing dengan melakukan perawatan mesin yang baik serta memberika pelatihan kepada pekerja dengan penggunaan suhu mesin sesuai jenis kain.Kata Kunci : Cacat Produk, Quality Improvement, FMEA, RPNa

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Fan, Jin Wei, Hong Xia Yan, Yu Hang Tang, and Yi Song. "Defects Cause Analysis Generated by Five-Axis NC Machine Tool and Optimization." Applied Mechanics and Materials 687-691 (November 2014): 353–58. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.353.

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In view of defects-"chew cutting" generated by the five-axis nc machine tool in the process of machining the S sample, the machine tool motion error model is established based on multi-body system theory. After that,combining sensitivity analysis theory with the research of machine tool processing defect causes.Then find out the main error terms which take great responsibility of machining defects and optimize related motion components,to meet accuracy requirements before leaving the factory.

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Zhang, Jian Fu, Zhi Meng Chen, Ping Fa Feng, and Wan Hong Xu. "The Characteristics of Titanium Alloy Chip-Breaking by Orthogonal Cutting with a Surface-Textured Cutting Tool." Applied Mechanics and Materials 365-366 (August 2013): 1235–39. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.1235.

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A comparative experimental study on the orthogonal cutting of titanium alloys by a polished tool, a tool containing a chip breaker groove, and a surface-textured tool was performed. The effects of different cutting tools on chip morphology, chip thickness, length and width of crack defects inside the chip, saw-teeth of the chip, and chip curl radius were analyzed during the cutting of a titanium alloy. Compared to chips formed by other tools, curled chip fragments formed by the surface-textured tool exhibited greater thickness and longer crack defect depths but smaller chip tooth pitches and curvature radii. The microstructural mechanisms involved in the interaction between the micro-texture surface cutting tool and the chips were analyzed by evaluating the cutting and texture parameters. The chip-breaking mechanism is that the micro-texture on the tool surface creates a sticky texture, leading to the micro-cutting and wrenching of chips, thereby increasing the magnitude of the tools work-hardening and chip-breaking effects.

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DANNY DHARMAWAN, LAURENTIUS, and YURIDA EKAWATI. "PENINGKATAN KUALITAS KNALPOT PADA PT FAJAR INDAH MENGGUNAKAN METODE SIX SIGMA." Jurnal Teknik Industri 15, no. 2 (March 3, 2016): 112. http://dx.doi.org/10.22219/jtiumm.vol15.no2.112-123.

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PT Fajar Indah adalah perusahaan yang bergerak pada bidang otomotif dimana salah satu produk andalannya adalah knalpot Colt Diesel FE 120 PS. Selama tahun 2012 dan 2013 PT Fajar Indah mampu memproduksi hingga 2400 unit knalpot dengan tingkat defect sebesar 6-7%. Terdapat lima jenis kecacatan yang memengaruhi kualitas dari produk knalpot ini, yaitu defect kip tutup, defect pada ring, defect ukuran sarangan, defect ukuran potong plat, dan defect plat pecah. Untuk mengetahui apakah pada proses produksi knalpot ini perlu dilakukan perbaikan dan bagaimana caranya maka dilakukan analisis six sigma. Analisis dilakukan melalui proses DMAIC dimana untuk penentuan usulan perbaikan melalui analisis RCA dan FMEA. Berdasarkan hasil analisis didapatkan bahwa PT Fajar Indah memiliki nilai DPMO dan sigma sebesar 12.879 dan 3,73 yang menunjukkan bahwa perbaikan masih perlu dilakukan pada proses produksi knalpot. Usulan perbaikan yang dapat dilakukan antara lain adalah menyusun jadwal maintenance,menyusun work instruction serta melakukan pengawasan, perbaikan cara penyimpanan cetakan ring, menyediakan tempat khusus untuk plat sisa hasil pemotongan, menambah jumlah pekerja untuk bagian inspeksi, dan mencari supplier yang mampu menyediakan plat dengan kualitas yang standar. PT Fajar Indah is an automotive company which is one of their flagship products is muffler for Colt Diesel FE 120 PS. During 2012 and 2013, PT Fajar Indah was able to produced muffler up to 2400 unit with 6-7% defects rate. There are five type of defects that affects muffler’s quality which are lid’s defects, ring’s defects, defects of resonator’s size, defects of plate’s cutting size, and defects of broken plate. To determine whether improvements are needed in muffler’s prodution process and how they will be conducted so six sigma will be used for analysis. Analysis was conducted using DMAIC process, where recommended action for quality improvement were determined with RCA and FMEA. Result from analysis shows that PT Fajar Indah had 12,879 DPMO value and 3.73 sigma which mean that improvement is needed in muffler’s production process. Some recommended actions that can be done are maintenance scheduling, making work instruction and supervise it, improving storage method for ring’s model, provide place for plate scraps from cutting process, adding more workesr for products inspection, and looking for suppliers who are able to provide plate with standard quality.

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Hassan, M. R., Mershad Mehrpouya, and S. Dawood. "Review of the Machining Difficulties of Nickel-Titanium Based Shape Memory Alloys." Applied Mechanics and Materials 564 (June 2014): 533–37. http://dx.doi.org/10.4028/www.scientific.net/amm.564.533.

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The purpose of this study is to identify machining difficulties of nickel-titanium based shape memory alloys. Nickel-titanium (Nitinol) is one the widely used shape memory material which is applied in many products in the aerospace, medical, and biomedical fields. NiTi alloy cannot be machined easily because of high tool wear, high cutting force, huge hardness and surface defects are made many problems into their machining. Investigation in micron precision shows plenty surface defects in machining process, something like debris of microchips, feed marks, tearing surface, deformed grains, material cracking and chip layer formation which consists the main problem in the machining of shape memory alloys. Moreover, these defects can be reduced or eliminated by changing the cutting parameters such as: feed rate, cutting speed and cutting depth so that, machining of nickel-titanium alloys would be improved.

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Popovic, Jelena, Jovanka Gasic, Slavoljub Zivkovic, Aleksandar Mitic, Marija Nikolic, and Radomir Barac. "Ultrastructural analysis of the surface of stainless steel endodontic instruments before and after use." Serbian Dental Journal 61, no. 4 (2014): 175–82. http://dx.doi.org/10.2298/sgs1404175p.

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Introduction. Although many studies have reported various advantages of nickel-titanium endodontic instruments, the use of stainless steel endodontic files still presents a standard in everyday practice. The aim of this study was to evaluate ultrastructure of the surface of stainless steel endodontic instruments before and after their use. Material and Methods. Fourteen sets of non-used stainless steel endodontic reamers and files were included in the study. Each set of instruments was used one, three or six times in simulated clinical conditions on extracted maxillary premolars. After their use the instruments were subjected to cleaning and sterilization procedures. Ultrastructure of the surface of instruments was observed under scanning electron microscope (SEM). Surface analysis was performed based on the number of uses and size of instruments. The following characteristics were analyzed: defects of instrument flutes, defects of cutting edges and instrument deformations. Results. SEM analysis showed defects on the surface of non-used instruments as a result of the manufacturing process. Surface defects, defects of cutting edges as well as flutes deformations were observed after a single use and were more often noticed in small sized instruments. After three uses, flutes deformations were observed in all small sized instruments and some of the medium size. After six uses all groups of instruments showed defects of cutting edges. Conclusion. Non-used stainless steel endodontic instruments showed surface defects created by the manufacturing process. Defects of cutting edges and flutes can be observed after a single use. To minimize complications and mistakes during clinical preparation it is recommended to limit the number of instrument uses.

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Gribanov, A. "IMPROVEMENT OF AUTOMATION SYSTEMS OF THE PROCESS BONDING LUMBER FOR THE LENGTH." Actual directions of scientific researches of the XXI century: theory and practice 8, no. 1 (October 26, 2020): 39–42. http://dx.doi.org/10.34220/2308-8877-2020-8-1-39-42.

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Resource conservation and reuse of wood processing waste in a modern market economy is of paramount importance. The technologies and technical equipment considered in the article are devoted to the process of splicing of short wood sections of lumber. The above stages of processing wood waste require optimally designed cutting cards for sawing raw materials in order to obtain the greatest yield of edged sawn timber. The studies of the method of manual cutting of wood defects considered in the article make it possible to determine the time spent on processing furniture blanks sent for subsequent splicing. Significant time is spent on inspection of lumber manually from four sides. The proposed optical method of wood flaw detection allows you to take into account the defects of the workpieces on four sides with the subsequent process of cutting them on the milling unit and automatic gluing along the length. It is proposed to use illuminated cameras, which are installed on four sides of the conveyor, as scanning elements. Photographs from the detectors are combined into a single three-dimensional map of the workpiece using special software and then transmitted in the form of control actions on the end face of the defect cutting line. Waste is automatically removed to the hopper by special pushing machines.

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Masoud, Fathi, S. M. Sapuan, Mohd Khairol Anuar Mohd Ariffin, Y. Nukman, and Emin Bayraktar. "Cutting Processes of Natural Fiber-Reinforced Polymer Composites." Polymers 12, no. 6 (June 11, 2020): 1332. http://dx.doi.org/10.3390/polym12061332.

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Recently, natural fiber-reinforced polymers (NFRPs) have become important materials in many engineering applications; thus, to employ these materials some final industrial processes are needed, such as cutting, trimming, and drilling. Because of the heterogeneous nature of NFRPs, which differs from homogeneous materials such as metals and polymers, several defects have emerged when processing the NFRPs through traditional cutting methods such as high surface roughness and material damage at cutting zone. In order to overcome these challenges, unconventional cutting methods were considered. Unconventional cutting methods did not take into account the effects of cutting forces, which are the main cause of cutting defects in traditional cutting processes. The most prominent unconventional cutting processes are abrasive waterjet (AWJM) and laser beam (LBM) cutting technologies, which are actually applied for cutting various NFRPs. In this study, previously significant studies on cutting NFRPs by AWJM and LBM are discussed. The surface roughness, kerf taper, and heat-affected zone (HAZ) represent the target output parameters that are influenced and controlled by the input parameters of each process. However, this topic requires further studies on widening the range of material thickness and input parameter values.

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Houyel, Lucile, and Sigolène M. Meilhac. "Heart Development and Congenital Structural Heart Defects." Annual Review of Genomics and Human Genetics 22, no. 1 (August 31, 2021): 257–84. http://dx.doi.org/10.1146/annurev-genom-083118-015012.

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Congenital heart disease is the most frequent birth defect and the leading cause of death for the fetus and in the first year of life. The wide phenotypic diversity of congenital heart defects requires expert diagnosis and sophisticated repair surgery. Although these defects have been described since the seventeenth century, it was only in 2005 that a consensus international nomenclature was adopted, followed by an international classification in 2017 to help provide better management of patients. Advances in genetic engineering, imaging, and omics analyses have uncovered mechanisms of heart formation and malformation in animal models, but approximately 80% of congenital heart defects have an unknown genetic origin. Here, we summarize current knowledge of congenital structural heart defects, intertwining clinical and fundamental research perspectives, with the aim to foster interdisciplinary collaborations at the cutting edge of each field. We also discuss remaining challenges in better understanding congenital heart defects and providing benefits to patients.

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Han, Shan Guo, De Tao Cai, Zi Yi Luo, De Jun Yan, He Xin Chen, and Kai Wang. "Study on the Laser Precision Cutting System and Stainless Steel Microporous Cutting Technology." Materials Science Forum 817 (April 2015): 342–47. http://dx.doi.org/10.4028/www.scientific.net/msf.817.342.

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In order to improve the quality of laser cutting of stainless steel porous, the investigation on cutting 0.12mm stainless steel plates was carried out by a50W-powerbridgefiber laser cutting machine.The influence of the auxiliary line angle, laser power, and the pulse width and gas pressure on the cutting quality was studied in this paper.The results show that fewer defects was found on the samples when the cutting angle of auxiliary line was 90°and few splash orburrswas found on the samplesby 40 Wlaser power, with 56 μs pulse width and 1.3MPa gas pressure.

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Takahashi, Naoki, and Jun Shinozuka. "Contributions of High-Speed Cutting and High Rake Angle to the Cutting Performance of Natural Rubber." International Journal of Automation Technology 8, no. 4 (July 5, 2014): 550–60. http://dx.doi.org/10.20965/ijat.2014.p0550.

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This study investigates the contributions of high-speed cutting and a high rake angle to the improvement of the cutting performance of natural rubber. Orthogonal cutting experiments were conducted at cutting speeds ranging from 1.0 m/s to 141.1 m/s. The rake angles examined were 0°, 20° and 50°. The following results were obtained from the experiments. The cutting ratio is almost 1.0 regardless of the cutting speed and rake angle. The cutting force rises rapidly as the cutting speed increases. High-speed cutting or a high rake angle eliminates tear defects on the machined surface and reduces chipping defects at the entry edge of the workpiece. An uncut portion, however, always remains at the exit edge. The cross-sectional shape of the machined surface becomes concave. Besides, the machined surface comes into broad contact with the clearance face. These degradations in the shape accuracy arise from the large elastic distortion that occurs in the shear zone. Increasing the cutting speed improves the flatness of the machined surface. Although an analysis of the cutting mechanism reveals that the apparent stiffness of the material in the shear zone is enhanced with increasing the cutting speed, a very high cutting speed worsens the shape accuracy because of the development of shock waves. Depending on the rake angle, there is a critical cutting speed that should not be exceeded to maximize the cutting performance of natural rubber.

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Dong, Guo Jun, Yuan Jing Zhang, Ming Zhou, and Yang Jun Wang. "The Research of Effect of Cutting Parameters on Machined Surface Defects in High-Speed Milling of SiCp/Al Composites." Key Engineering Materials 589-590 (October 2013): 245–51. http://dx.doi.org/10.4028/www.scientific.net/kem.589-590.245.

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The silicon carbide reinforced aluminum matrix composites (SiCp/Al) are widely used for its high specific stiffness and high specific strength. However, the poor surface quality and machined surface defects limit its further application. The aim of this paper is to investigate the effect of cutting parameters on the machined surface defects in high-speed milling of SiCp/Al composites. The tests were performed on a high precision computerized numerical control (CNC) precision milling machine using a polycrystalline diamond (PCD) tool, and the machined surfaces were measured by the scanning electron microscope (SEM).It was found that cutting parameters have a great influence on the depth of big pits. A high feed rate and a low cutting speed correspond with a big cutting force, and result in a large depth of big pits.

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Bañon, Fermin, Alejandro Sambruno, Sergio Fernandez-Vidal, and Severo Raul Fernandez-Vidal. "One-Shot Drilling Analysis of Stack CFRP/UNS A92024 Bonding by Adhesive." Materials 12, no. 1 (January 6, 2019): 160. http://dx.doi.org/10.3390/ma12010160.

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The use of adhesive layers can improve the properties and reduce the defects produced in the interfaces. This provides adherence to the structure, adapting the joining surfaces and avoiding spaces between the layers. However, the presence of the adhesive can potentiate the defects caused during drilling. In turn, a loss of adhesive in the interface can occur during machining affecting the final structure. This work has followed a conventional OSD strategy in CFRP and UNS A92024 aluminium sheet stacking with adhesive. A series of dry drilling tests have been developed with different cutting conditions and new noncoated WC-Co helical cutting tools. Analysis of Variance (ANOVA) statistical analyses and surface response models have been applied to determine the mechanical behaviour in the holes. For this purpose, the dimensional deviation, surface quality, and adhesive loss in the interface in relation to the number of holes have been considered. A combination of cutting parameters that minimizes the evaluated defects has been found. Diametric deviations and surface qualities below 2% and 3.5 µm have been measured in the materials that make up the stack with cutting speeds higher than 140 m/min and feed rates between 200 and 250 mm/min. However, the greatest adhesive losses occur at high cutting speeds.

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Maiya, Shreesha S., Smruti V. Patel, Chinnaswamy Reddy, and Suresh V. Pujar. "Percutaneous closure of multiple ventricular septal defects: simultaneous use of muscular ventricular septal defect device and Multi-Fenestrated Septal Occluder – “Cribriform” to close residual ventricular septal defects after complex cardiac surgery in a child." Cardiology in the Young 27, no. 1 (July 5, 2016): 181–83. http://dx.doi.org/10.1017/s1047951116000925.

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AbstractA male child, with d-transposition of great arteries, a large perimembranous ventricular septal defect, multiple additional ventricular septal defects, small muscle-bound right ventricle, and severe pulmonary stenosis with confluent, moderate-sized branch pulmonary arteries, underwent an emergency right modified Blalock–Taussig shunt on day 15 of life and réparation à l’étageventriculaire procedure with ventricular septal defect closure with takedown of the Blalock–Taussig shunt at 2.5 years of age. On follow-up, he showed a moderate residual upper ventricular septal defect and multiple apical ventricular septal defects, mild mid-right pulmonary artery stenosis, free pulmonary regurgitation, and right ventricular dysfunction. Surgical re-intervention was deemed extremely risky, the upper muscular ventricular septal defect was closed using an 8-mm Amplatzer Muscular Ventricular Septal Defect Occluder Device, and an 18 mm Amplatzer Multi-Fenestrated Septal Occluder – Cribriform was used for the multiple apical muscular ventricular septal defects. After 1 year, his right pulmonary artery stenosis worsened, for which right pulmonary artery angioplasty was carried out using an 8×20 mm cutting balloon followed by a 10×20 mm Tyshak II balloon. This is the only case reported for the paediatric age group using a cribriform septal occluder device for percutaneous closure of multiple apical ventricular septal defects.

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Hutyrová, Zuzana, Michal Hatala, Jozef Mihok, Peter Michalik, Ján Duplák, and Svtelana Radchenko. "Non-Destructive Testing of Inhomogeneity of Wood Plastic Composite." Applied Mechanics and Materials 718 (December 2014): 71–76. http://dx.doi.org/10.4028/www.scientific.net/amm.718.71.

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The purpose of this study is to investigate of Non-Destructive Testing of Wood Plastic Composite (WPC), where the axis errors are mainly cracks caused by not change of cutting conditions (cutting speed and feed rate), respectively geometry of he cutting tool, but their imperfect encapsulation of wood with plastic (HDPE). Detection of surface defects was used visual inspection, colour penetrate test and fluorescent penetrate method. To detect internal defects was used X-ray. Pictures taken with a digital microscope camera does not provide sufficient information about internal defects, captures only the surface and as a result it is postulated that the cracks are spreading along the length of the profile extrusion axis (it is not possible to state their course in different layers – cross section along the thickness). Solution is use of the new technology – connection of metrology and tomography – metrotomography (X-ray scanning).

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Wu, Dongxu, Peng Zhang, Huiming Wang, Zheng Qiao, and Bo Wang. "Effect of cutting parameters on surface quality during diamond turning of micro-prism array." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 231, no. 3 (August 6, 2016): 555–61. http://dx.doi.org/10.1177/0954405415625925.

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In order to achieve the high-quality roller mold used in roll-to-roll fabrication of optical prism films, this article investigates the effects of cutting parameters on surface quality during diamond turning of micro-prism array, and some cutting experiments are carried out on home-made ultra-precision drum roll lathe. The surface defects such as micro pits and burrs are presented and discussed at different cutting parameters. The experimental results show that, when the cutting depth is more than 4 µm, the plowing force becomes the dominant factor to remove material, which may cause the generation of micro pits on the side surface of micro prism. During multiple-step diamond turning of micro-prism array, the final cutting depth is recommended not to exceed 2 µm; in this case, there is no generation of micro pits and the height of burr is less than 13.6 nm. Moreover, the well-controlled cooling and chip evacuation can effectively improve the influence of cutting speed on surface quality. Finally, micro-prism array with pitch of 40 µm is successfully machined without apparent surface defects.

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Bañon, Fermin, Alejandro Sambruno, Leandro González-Rovira, Juan Manuel Vazquez-Martinez, and Jorge Salguero. "A Review on the Abrasive Water-Jet Machining of Metal–Carbon Fiber Hybrid Materials." Metals 11, no. 1 (January 17, 2021): 164. http://dx.doi.org/10.3390/met11010164.

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The bonding of metallic alloys and composite materials in the form of a hybrid structure is a line of great interest for the current industry. The different machinability of both materials requires a specific machining process. Abrasive water-jet machining (AWJM) is an excellent technology for the simultaneous machining of both materials. However, defects at the micro and macro-geometric level have been detected in several scientific articles. In this review, a detailed study of the two main defects in metals, composite materials and hybrid structures has been developed. The conclusions of several scientific articles have been exposed for a better understanding of the topic in articles between 1984 and 2020. The influence of the cutting parameters on the reduction in kinetic energy of the water jet and the order of stacking of the materials in the hybrid structure is the main objective in order to minimize these defects. Cutting parameter optimization studies, predictive model proposals, process-associated defects and evaluation methodologies have been discussed. The aim of this article is to set a solid background on AWJM machining in hybrid structures and on the influence of cutting parameters on generated defects and machining strategies to obtain the best results at a macro and micro-geometric level.

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LeBlanc, Jacques G., Jennifer L. Russell, James E. Potts, Margaret L. Deagle, and Suvro S. Sett. "Surgical Closure of Secundum Atrial Septal Defects: The Cutting Edge?" Asian Cardiovascular and Thoracic Annals 9, no. 3 (September 2001): 192–95. http://dx.doi.org/10.1177/021849230100900307.

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Croll, Theodore P. "Hastening the Enamel Microabrasion Procedure Eliminating Defects, Cutting Treatment Time." Journal of the American Dental Association 124, no. 4 (April 1993): 87–90. http://dx.doi.org/10.14219/jada.archive.1993.0083.

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Kondo, Yasuo, and Satoshi Sakamoto. "A Damage-Free Machining Method for CFRP Without Feedback Control Systems." International Journal of Automation Technology 10, no. 3 (May 2, 2016): 318–23. http://dx.doi.org/10.20965/ijat.2016.p0318.

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A damage-free cutting method called the constant- load feeding method is proposed as a high-precision machining method in carbon-fiber-reinforced plastic (CFRP) cutting. The constant-load feeding method can minimize cutting defects such as burrs and scuffing during diamond-saw cutting. In addition, there was no apparent cutting damage to the cutting surface from drilling with a high-speed steel twist drill. The cutting resistance was kept at a constant value during the entire process. The constant-load feeding can self-regulate the optimal tool feed rate to realize damage-free machining of CFRP composites without any feedback control systems based on the cutting-force.

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Mochammad Iqbal Syidik, M Dzikron, and Iyan Bachtiar. "Perbaikan Kualitas Produk Tas Kulit dengan Menggunakan Metode Teorija Rezhenija Izobretatelskih Zadach (TRIZ) pada CV. X – Bandung." Jurnal Riset Teknik Industri 1, no. 1 (July 6, 2021): 43–48. http://dx.doi.org/10.29313/jrti.v1i1.95.

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Abstract. CV. X is a company engaged in the leather industry that manufactures wallets, bags and key chains. The company experienced a decrease in sales volume due to a decrease in product quality from defective products in the company. Leather bags have an average percentage of disability of 2.39% in 2017-2018 from the company's disability limit of 2%. The existence of these defective products requires companies to improve product quality to reduce the occurrence of defects. The method used to solve the problems that are being faced by the company is the Seven Tools Quality Control method to identify the causes of product defects, while the Rezhenija Izobretatelskih Zadach (TRIZ) method is used to design a product quality improvement plan. The result of data processing which becomes the main priority is defect cutting. The causes of cutting defects include decreased work concentration, inadequate workers, poor physical condition, no machine maintenance, blunt cutting machines, high cutting machine use intensity, work environment, hot room temperature, lack of work space lighting. All causes of product defects are designed to improve the quality of leather bag products by creating visual controls, forms for worker health, cutting knife replacement machines, installing air conditioners, and adding lights to the sewing machine. Abstrak. CV. X merupakan perusahaan yang bergerak di bidang industri kulit yang memproduksi dompet, tas, dan gantungan kunci. Perusahaan mengalami penurunan volume penjualan yang disebabkan karena adanya penurunan kualitas produk dari produk cacat di perusahaan. Tas kulit memiliki rata-rata persentase kecacatan sebesar 2,39% pada tahun 2017-2018 dari batas kecatatan yang ditetapkan perusahaan sebesar 2%. Adanya produk cacat tersebut mengharuskan perusahaan melakukan perbaikan kualitas produk untuk mengurangi terjadinya kecacatan. Metode yang digunakan untuk menyelesaikan permasalahan yang sedang dihadapi oleh perusahaan yaitu metode Seven Tools Quality Control untuk mengidentifikasi penyebab terjadinya kecacatan produk, sedangkan metode Teorija Rezhenija Izobretatelskih Zadach (TRIZ) digunakan untuk membuat rancangan perbaikan kualitas produk. Hasil pengolahan data yang menjadi prioritas utama yaitu cacat potong. Penyebab cacat potong diantaranya yaitu konsentrasi kerja menurun, pekerja kurang hati-hati kondisi fisik kurang baik, tidak ada perawatan mesin, mesin potong tumpul, intesitas penggunaan mesin potong tinggi, lingkungan kerja, suhu ruangan panas, pencahayaan ruang kerja kurang. Semua penyebab cacat produk dibuat rancangan perbaikan untuk meningkatkan kembali kualitas produk tas kulit dengan membuat visual control, form untuk kesehatan pekerja, mesin penggantian pisau potong, pemasangan AC, serta penambahan lampu pada meisn jahit.

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Drotár, Atila, Pavol Zubko, Alicia Mašlejová, Peter Kalmár, Peter Vranec, Slavka Hockicková, Mária Demčáková, and Lucia Hrabčáková. "Defects of Steel Sheets Joined by Laser Welding." Defect and Diffusion Forum 405 (November 2020): 240–44. http://dx.doi.org/10.4028/www.scientific.net/ddf.405.240.

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Introduction of new technologies demands a new access to quality evaluation of products. Joining of steel sheets with laser butt welding requires increased demand on precision of welded sheet ends alignment as well as condition of cutting edge. Moreover, increased requirements are placed on purity of environment, flatness of strips, gases, etc. The paper deals with evaluation of quality of laser butt welds of steel sheets and description of defects which could occur on welds from the metallographic point of view. The influence of relative displacement of welded strips ends alignment, different relative sheet thickness alignment, welding gap size and quality of sheet shear edge on quality of weld will be described. The most significant effect on quality of weld joints and their final mechanical properties has relative position of strip ends and geometry of cutting edge.

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Голубенко, Юрий, Yuriy Golubenko, Александр Богданов, Aleksandr Bogdanov, Екатерина Тюльпанова, and Ekaterina Tyulpanova. "Peculiarities in polymer laser cutting." Science intensive technologies in mechanical engineering 1, no. 10 (September 9, 2016): 33–38. http://dx.doi.org/10.12737/21426.

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In this paper the application of laser cutting methods for polymeric materials working is under consideration. The authors analyze the laser beam effect upon polymers reasoning from the peculiarities of their structure and properties. The methods to eliminate defects at polymer laser cutting, the methods to increase the interaction effectiveness of radiation with material, process quality are offered. To determine the dependences of a cut width and a value of flash formed at the beam input and its output of material worked there were carried out experiments at different rates and constant capacity of CO2-laser. According the results of the researches carried out the optimum working modes were established.

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Tian, Xin Li, Hao Wang, Xiu Jian Tang, Zhao Li, and Ai Bing Yu. "Edge Design for Regrinding Cutting Tool." Applied Mechanics and Materials 101-102 (September 2011): 938–41. http://dx.doi.org/10.4028/www.scientific.net/amm.101-102.938.

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Regrinding of wasted cutting tools can recycle resources and decrease manufacturing costs. Influence of relative tool sharpness and tool cutting edge angle on tool edge radius were analyzed. Cutting force and cutting temperature were simulated with FEM on different edge radius. Edge preparation experiments were carried out though an abrasive nylon brushing method. The results show that RTS and cutting edge angle have influence on edge radius. Small edge radius might result in small cutting forces and lower average temperatures, could maintain the cutting state between tool and workpiece. The cutting edge defects can be eliminated through edge preparation, and a smooth cutting edge can be obtained. Cutting tool life will be improved through proper edge design and edge preparation.

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Xia, Ji Sheng, Qing Zhu Jia, and Zhen Zhen Sun. "Pre-Mixed Abrasive Water Jet Cutting in the Marble." Advanced Materials Research 981 (July 2014): 818–21. http://dx.doi.org/10.4028/www.scientific.net/amr.981.818.

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High-pressure abrasive water jet cutting is a cold and non-traditional method, with many advantage which the traditional processing do not have.The traditional method of cutting marble have rough sections, poor dimensional accuracy, large seam, high tool cost and the processing efficiency is low. Can be considered high-pressure abrasive water jet cutting to improve its traditional cutting defects. This article explores the use of the pre-mixed abrasive water jet cutting in the marble, and its comparison with traditional methods, highlighting the advantages which the pre-mixed abrasive water jet cutting in the marble.

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Journal articles on the topic 'Cutting defects'

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