Width Of Cut Research Articles

Effect of Variation of Dragline Bench Height and Cut Width on Performance of Tandem Dragline Operations in Large Opencast Coal Mines in India

Effect of Variation of Dragline Bench Height and Cut Width on Performance of Tandem Dragline Operations in Large Opencast Coal Mines in India

The effect of the feed rate and revolutions of the cutting tool on the amounts of created chips in dust and respirable sizes from milling particleboards, and medium-density fibreboards

The CNC finish milling of wood-based materials creates chips in a wide size range, where considerable amounts were found even below <10.0μm. The presented article studied the effect of technological variables on determined amounts of chips in dust sizes and respirable range from medium-density fibreboards (MDF) and particleboards (PTCB). The materials were milled at a constant width of cut (ae) by 1mm, with the feed speed (vf) in the range of 6, 8, 10, and 12m·min-1, and with revolutions of the cutting tool (n) in the range of 16,000; 18,000; and 20,000revs·min-1. In dust size, we cover chips in the size range below <0.125mm, and respirable size below <10.0μm. The dust sizes from collected chip samples were determined by sieve analysis with pre-defined mesh sizes by weighting the retained mass on specific sieves and with the laser analysis we estimated the amounts of chips in sizes <10.0μm. The number of chips in the dust size ranged for MDF by 34.7-40.8w% and in PTCB by 38.1-54.7w%. Amount of chips in respirable size for MDF by 0.01-18% and for PTCB by 0.01-4.5% of the total mass volume. Increasing the (vf) from 6 to 12m/min significantly lowered amounts of Fine and chips in respirable size (p<0.05) in PTCB, no matter on adjusted cutting tool (n). In MDF such effect was observed only with (n) 20000revs/min for respirable sizes.

Investigating the effect of deicing parameters using high-pressure water jet

Maritime operations are impacted by ice accretion on decks, bulkheads, and offshore structures during the winter or in extremely frigid climates. In most cases, the traditional method of deicing maritime vessels is human labor, which requires enormous effort and lengthy hours for unsatisfactory results, particularly when the ice adhesion strength is high. This study experimentally examined combined effects of operational parameters, including operating pump pressure, nozzle geometry, water jet temperature, standoff distance, and time of cut, on the depth and width of a cut through an ice block. In comparison to other parameters, the influence of nozzle geometry on both the width and depth of cut was found to be more significant, with R-squared values of 85% and 62% respectively. Increasing the depth and width of the cut facilitated the delamination and disintegration of ice from an aluminum mold. This indicates that water jet deicing on maritime vessels could be effective, therefore achieving the objective of this study. The optimization of operational parameters is used to develop a cuttability chart for various thicknesses of accumulated ice on marine vessels.

Numerical modeling of heat flux in ultrasonic-assisted grinding of difficult-to-cut materials with a pressurized lubrication system

The temperature measurement during grinding process is difficult due to work–wheel interactions and nearby coolant layers. Surface integrity also gets affected by the grinding burns caused due to high heat generation. Therefore, the theoretical temperature estimation could provide prior detection of grinding burns. This article presents an analytical model to predict the heat flux in pressurized lubricated ultrasonic-assisted surface grinding of Nimonic 80 A using Cubic Boron Nitride (cBN) grinding wheel (vitrified grinding bond, grit 80/100, concentration 100%). In this process, the high frequency of ultrasonic vibration and low amplitude is employed to vibrate the workpiece. In the current modeling approach, the motion analysis of grains has been estimated initially, which provided the effective grinding force. This effective grinding force was then utilized to obtain the analytical model of heat flux. Finally, the model was formulated by considering the effect of heat conducted into the material and heat released due to the lubrication system. The established model comprised the effects of lubricating and machining parameters such as dynamic viscosity of cutting fluid, pressure, diameter and length of cutting fluid pipes, width of cut, frequency, speed of table, amplitude, depth of cut and speed of the wheel. This numerical model revealed affirmative results substantiated by experimentally procured data. This developed model can add to the direction of sustainable grinding approach.

Optimization of micro-ECDM performances during micro-channeling on glass using Taguchi technique

The present research work is aimed toward optimize the micro-ECDM (Electro Chemical Discharge Machining) parameters like applied voltage, electrolyte concentration, duty ratio and pulse frequency on the optimum micro-channeling performances on borosilicate glass. Micro-ECDM tests were performed on borosilicate glass in well-established ECDM set-up under different applied voltage, electrolyte concentrations, duty ratios and pulse frequencies. Several micro-ECDM performances on glass like material removal rate (MRR), surface roughness (SR) and width of cut (WOC) were investigated for every matching test condition. The signal noise (S/N) ratio and best fitted ANOVA analysis as-well-as predicted results, mean and standard deviation has been propounded during micro-channel machining process. Heat affected zone, radial overcut and morphology of debris were investigated under scanning electron microscope. The micro-ECDM parameters have been optimized by applying Taguchi Technique on the experimental results and observations. The optimum micro-channeling performances during micro-ECDM process on glass are observed at applied voltage of 50 V, 25 wt% electrolyte concentration, 0.5 duty ratio and 50 Hz pulse frequency.

Analysis of Tool Load Concerning the Cross-Sectional Size of Removed Material

High-feed milling (HFM) represents a progressive manufacturing technology that has recently found widespread application across various industries. HFM is characterized by high machining speed, reduced cycle times, increased overall productivity, and increased tool life. Due to its versatility, HFM is a suitable technology for the application of various materials. The study deals with experimental analysis of cutting forces, machined surface integrity, and statistical evaluation in high-feed machining. In the present study, nickel-copper-based alloy (Monel) was chosen as the machined material, employing HFM with a monolithic ceramic milling cutter. The Monel material is characterized by its excellent mechanical properties and chemical resistance in harsh environments. During machining, cutting forces were recorded in three mutually perpendicular directions. This paper delves into the analysis of the impact of the depth of cut (ap), width of cut (ae), and lead-in angle (ε). The chosen evaluation characteristics encompass the tool load, primary profile, and the attained roughness of the machined surface. It is noteworthy that the technology under consideration predominantly aligns with the roughing phase of the manufacturing process. Additionally, the investigation incorporates a statistical analysis of the response surface pertaining to the cutting force components, namely Fx, Fy, Fz, and the resultant cutting force F.

Cutting processability of metal-ion-containing cellulose nanofibril films by continuous wave laser

Understanding the cutting processability of cellulose nanofibril (CNF) films by continuous wave laser is important for precise shape processing that closely follows the design pattern. In this study, laser cutting of films made of surface-carboxylated CNFs with various counterionic species was performed to explore the factors that control the cutting processability. The cut width and the thermally affected width are mainly controlled by the laser irradiation energy per unit length. The processed cross section is tapered and rises above the film thickness. NMR analysis suggests that the pyrolysates contain water-soluble cello-oligosaccharides, the molecular weight of which varies with the type of CNF film. We consequently demonstrated that the COOH-type CNF film is preferable to the COONa-type CNF film for reducing the coloration residue and for processing the film into a shape that best follows the designed processing pattern.

Experimental investigation on effect of perforated double V-cut twisted tape on thermo-hydraulic characteristics of heat exchanger tube

ABSTRACT To enhance overall thermal performance factor of tubular heat exchanger, use of twisted tape has been very effective. Twisted tape creates turbulence in the flow which enhances rate of heat transfer and friction factor. Present experimental study aims to limit this penalty of increase in friction factor and achieve high thermal performance factor. For this, present article analyzes the effect of different design modifications in twisted tape on thermo-hydraulic performance of heat exchanger tube. Different inserts, i.e. Simple Twisted tape (STT), Double V-Cut Twisted Tape (DVCTT) and Perforated Double V-Cut Twisted Tape (PDVCTT), of varying twist ratio (TR) 3, 4 and 5 are considered for the investigation. Further design modification such as V-cut with width of cut (wc) 5 mm, depth of cut (dc) 4 mm, and perforation of 5 mm diameter is produced in twisted tape. Water is used as the working fluid for the study. Data pertaining to Nusselt number and friction factor is collected for the analysis in turbulent region where Reynolds number varied from 4000 to 16,000. Maximum enhancement in Nusselt number and friction factor is recorded 2.44 times and 3.71 times of plain tube respectively at Re = 4000 in case of TR = 3. Further PDVCTT leads to maximum decrement in Nusselt number and friction factor 3.83% and 27.35% when compared with DVCTT. Maximum thermal performance obtained is 1.71 in case of PDVCTT with TR of 3 at Re = 4000.

Hybrid modeling and optimization of fiber laser hole cutting of austenitic stainless-steel sheets using response surface

In this study, an efficient approach was proposed to systematically model and optimize the laser small hole cutting process parameters using a hybrid approach for the design of experiment and multi-objective genetic algorithm optimization. The central composite design and response surface methodology were used to effectively model the impact of four main factors: cutting speed, laser power, gas pressure and focal distance on the responses. The responses considered were hole diameter circularity tolerance, spattering and cut kerf width, which were used to evaluate the quality of the laser hole cutting. The regression equations were used to model the effect of process parameters and their interactions on the responses. These regression models were then used as objective functions for optimization. The results show that the focal distance and laser power have had a significant influence on the hole diameter circularity tolerance and the variation in size of the cut kerf. In particular, the melted material spattering rate increased threefold when the focal distance increased from 0.4 to 0.8 mm. The optimization results highlighted that the best outcomes in terms of minimum deviation, spatter, and the cut-kerf width were achieved at low power (between 605 and 685 W) and low speeds (in the range of 11.1–12.7 m min−1). The optimal focal distance for all solutions was found to be 0 mm for the gas pressure (between 6.5 and 8 bars) to minimize the objective functions.

Influence of generator parameters on cutting width during WEDM process

The primary objective of this paper is to rigorously analyse the influence of selected parameters on the cut width in the context of Wire Electric Discharge Machining (WEDM). The parameters under investigation, each varied at different levels, include pulse width, servo reference mean voltage, time interval between two pulses, discharge frequency, and wire feed speed. As the workpiece material, sintered carbide K10 was used. Data for the response variable, cut width, was meticulously collected using two high-precision instruments: the Zoller Genius 3s and the Alicona InfiniteFocusSL. Among the parameters studied, the mean reference voltage emerged as the most influential variable. It holds a commanding lead with a percentage contribution of as much as 82.4 %, making it nearly 15 times more impactful than the second most influential parameter, which is pulse width. At its lowest setting, or first level, the mean reference voltage results in a record low cut width. Conversely, at its highest setting, or third level, it leads to a record high cut width. This comprehensive analysis not only quantifies the relative importance of each parameter but also provides valuable insights into the optimal settings for achieving desired cut widths. The findings have significant implications for improving the efficiency and precision of WEDM processes.

A combined approach of artificial neural network, multi-objective genetic algorithm, and response surface methodology for enhanced PMMA micro-channeling in low power fiber laser beam machining

The most cost-effective approach for generating micro-channels on polymethyl methacrylate (PMMA), a polymer highly sought after in the biomedical industry, is by employing laser technology. The study aims to evaluate the feasibility of utilizing a low-power fiber laser for the purpose of generating micro-channels on PMMA, as well as enhance the data analysis and forecasting of results for implementation in the biomedical sector. This study utilizes response surface methodology (RSM) to conduct experiments by creating micro-channels on PMMA using low-power fiber lasers. Furthermore, a multi-objective genetic algorithm (MOGA) is employed to optimize the responses, namely the cut width and depth, within the predetermined range of process parameters. Moreover, the artificial neural network (ANN) technique is utilized to predict the results of MOGA and RSM. The study encompasses process parameters such as laser power, pulse frequency, scan speed, and number of passes. The ANN is trained using input-output patterns derived from RSM. Three methods are integrated not only to optimize but also to forecast the data set in order to reduce material waste, costs, and increase efficiency. The experimental research shows that the artificial neural network technique has higher prediction accuracy compared to the other two methods. All three strategies utilized in this study have been well aligned with the empirical results for predicting the dimensions of the micro-channels.

Prediction of quality characteristics of micro-channels by deep learning algorithm during laser transmission ablation of PMMA

Underwater laser transmission micro-channelling of thick transparent polymethyl methacrylate (PMMA) using a neodymium-doped yttrium aluminium garnet (Nd: YAG) laser is the focus of this study. Experiments are conducted to determine the effect of three significant variables, namely pulse frequency, lamp current, and cutting speed, on heat-affected zone (HAZ) width, cut depth, and kerf width. Experiments are designed systematically utilising the full factorial design method. The purpose of constructing empirical models, specifically non-linear ones, is to establish and clarify the relationship between control factors and corresponding responses. A feed forward backpropagation neural network (FF-BPNN) is employed for predicting the measured response. Additionally, an assessment is made between the FF-BPNN results and the values predicted by the model. On the basis of the anticipated results, it can be concluded that the FF-BPNN model is preferable in predicting both the depth of cut and kerf width. In contrast, when specifically contemplating the measurement of HAZ width, the application of a non-linear model is more advantageous. As a measure of accuracy, the mean absolute error is computed for both the feedforward backpropagation neural network (FF-BPNN) and the nonlinear modelling technique.

МОДЕЛЮВАННЯ ТА ОПТИМІЗАЦІЯ ПРОЦЕСУ ЛАЗЕРНОГО РІЗАННЯ МЕДИЧНОГО ЕНДОПРОТЕЗА (СТЕНТА)

When designing technological processes, developers always face tasks aimed at increasing the efficiency of the laser cutting process of tubular blanks, as well as improving technological equipment. The main efforts are aimed at improving the quality indicators, in particular the roughness of the cut surface, as well as the elastic characteristics of medical endoprostheses.The analysis of scientists' research on laser processing of medical endoprostheses made it possible to determine the main priority directions of scientific research, namely the search for ways to improve experimental equipment and optimal control parameters of the technological process of laser processing of tubular thin-walled blanks.The purpose of this is to increase the elastic characteristics of the medical endoprosthesis, in particular its flexibility due to the reduction of the width of the cut, as well as the optimization of the technologicalprocess of laser cutting of the tubular thin-walled blank.On the basis of a priori information, methods and approaches were developed to improve technological equipment in order to increase the productivity and quality of manufacturing medical endoprostheses. Namely, a complex approach was developed to increase the elastic characteristics of the stent by reducing the width of the laser cut. In particular, the methods of mathematical statistics were used for the effective analysis of technological factors affecting the process of laser treatment of medical endopros-theses. Namely, mathematical models of the process of laser cutting of thin-walled tubular blanks were obtained.In this work, the optimal configuration of the experimental prototype of experimental equipment for the manufacture of medical endoprostheses (stents) was developed. Also, a technique was developed and optimization of the control parameters of the process of laser cutting of tubular blanks was carried out. The results of experimental studies showed the possibility of reducing the width of the laser cut, which made it possible to improve the elastic characteristics of the medical endoprosthesis.

Experimental Investigations on Cutting Rate and Kerf Width on Wire-Electro Discharge Machining of Silicon Nitride – Titanium Nitride Ceramic Composite

The growing benefits of ceramic composites in their usages in automotive, Bio medical implants, nuclear, and aircraft industries make them the most sought-after significant material. However, cutting these composites with traditional machining is very challenging. The non-traditional machining process like electric discharge machining (EDM) are crucial to machine them. Wire EDM is equipped to machine any kind of material, regardless of how it naturally behaves. Using a coated copper electrode, the current work focusses on investigation of the effects of Wire EDM parameters on Si3N4-TiN ceramic composite. The major machining parameters are servo voltage, short pulse on time, and pulse on time, which were varied over five levels, whereas cutting rate and width of cut are considered as the machining performance characteristics. Using Response Surface Methodology (RSM) that is based on Design of Experiments (DOE) the distinctive characteristics of the WEDM process are investigated. Empirical models have been created for cutting rate and kerf width. According to the findings, the servo voltage is the second most important component, after the pulse-on time.

Influence of the width of cut in ultrasonic vibration superimposed face milling of X46Cr13 and X40CrMoV5-1 on the surface microstructure and CVD diamond coating adhesion

Ultrasonic vibration superimposed milling (UVSM) with an oscillating movement of the specimen in the direction of the tool axis is an efficient method for the generation of microstructured functional surfaces. The application of end milling cutters with a diameter smaller than the length and the width of the surface to be structured generally results in recuts and path overlaps. In order to avoid surface recutting, a small lead angle was realized by slightly tilting the ultrasonic system with the specimen. The overlapping area of two adjacent paths was kinematically simulated for different widths of cut (from 70% to 90% of the tool diameter). Cutting experiments were carried out by UVSM of X46Cr13 and X40CrMoV5-1 steel specimens to investigate the influence of the width of cut on the surface generated in the overlapping area and also the adherence of a subsequently deposited CVD diamond layer. For this purpose, 3-D laser scanning microscopy and SEM analysis were applied. The knowledge gained allows for designing UVSM processes, especially regarding 3-D freeform surfaces with defined microstructures subjected to CVD diamond coating.

Investigation of the technological profile of illegally distributed tobacco derivatives and smoking products

The current investigation includes technological assessment and interpretation of the profile of tobaccos, tobacco derivatives and smoking products illegally distributed in Bulgaria, as officially provided for expertise in the Tobacco and Tobacco Products Institute (TTPI) by external contractors (legitimate state structures) in 2021. The physical and chemical properties of the tobacco objects, depending on their nature, were determined according to standardized methods. The biggest share in the analyses (139 in total) took the determination of tobacco cut width (39%) and particle size fractionation (37%), which supported the observation that the illicit tobacco market in Bulgaria is recently dominated by cut tobacco for hand-rolled cigarettes. In the cut tobacco predominated long and medium-sized strands, but in widely varying proportions (42.27-81.78% and 9.98-38.46%, respectively), with cut width in 0.59-1.06 mm range. The sieve analysis and the expert examination of the tobacco derivatives revealed that they were undoubtedly technological tobacco waste, and, respectively, that accentuated data must be communicated to consumers about the risks associated with the smoking of such tobacco articles. It was found that all illicitly traded fine-cut tobacco blends produced considerably higher tar (12.25-16.05 mg/cig) and CO (12.74-16.94 mg/cig) emissions than the limits set for conventional cigarettes.

Simulation and experimental investigation of the effects of subdicing on a single element transducer

Structure design of medical ultrasonic transducers is of prime importance, as it not only affects the transducer's imaging performance, but also limits its application scene and scope. In this paper, a single element transducer with subdicing is fabricated and its performance is studied using finite element method. In addition, the comparison transducers (CPTs) are fabricated as well as single element transducers with and without subdicing the element. The experimental results show that by subdicing the element with cut width 120 μm and cut depth 500 μm of the single transducer with a center frequency of 8 MHz and dimension of 2 mm × 0.9 mm × 1.2 mm, the center frequency reduced by up to 58.3 %, the −6 dB bandwidth increased by up to 48.7 %, but the echo signal amplitude reduced by 52.4 %. Compared to CPT-5, the volume of the subdicing transducer reduced by 94.6 %, the center frequency reduced by 4.3 %, the −6 dB bandwidth increased by 1.26 times, the transmitted pulse signal length decreased by 50 %, and the echo signal amplitude achieved 28 % of CPT-5. Therefore, the proposed subdicing transducer may have great potential for miniaturization and close-range imaging.

OPTIMIZATION OF CUT QUALITY FOR AWJ PROCESSING OF A STEEL ALLOY

Abrasive water jet (AWJ) has gained an important place among the machining technologies due to its capacity to cut complex shapes in various materials without thermal effects and with low cutting forces, but it also has a reduced environmental impact. A key element for the quality of the cut is the amount of energy contained in the abrasive jet. The dissipaton of energy leads to kerf taper, high values of surface roughness, surface striations, the deviation of the water jet (jet drag), and even insufficient penetration. The current paper investigates the influence of process parameters on the quality of the cut for a S235 steel alloy. The quality of the cut was assessed by four parameters: entrance width of cut (Li), exit width of cut (Le), perpendicularity (u) and kerf angle (α). The experiments were organized according to a D-optimal Response Surface Method. Analysis of variance (ANOVA) was used for the development of a mathematical model that correlates the influence of process parameters on the quality of the cut. Finally, an optimization of the process parameters was proposed.

PREDICTION OF RESPONSES IN A CNC MILLING OPERATION USING RANDOM FOREST REGRESSOR

In the present-day manufacturing environment, the modeling of a machining process with the help of statistical and machine learning techniques in order to understand the material removal mechanism and study the influences of the input parameters on the responses has become essential for cost optimization and effective resource utilization. In this paper, using a past CNC face milling dataset with 27 experimental observations, a random forest (RF) regressor is employed to effectively predict the response values of the said process for given sets of input parameters. The considered milling dataset consists of four input parameters, i.e. cutting speed, feed rate, depth of cut and width of cut, and three responses, i.e. material removal rate, surface roughness and active energy consumption. The RF regressor is an ensemble learning method where multiple decision trees are combined together to provide better prediction results with minimum variance and overfitting of data. Its prediction performance is validated using five statistical metrics, i.e. mean absolute percentage error, root mean squared percentage error, root mean squared logarithmic error, correlation coefficient and root relative squared error. It is observed that the RF regressor can be deployed as an effective prediction tool with minimum feature selection for any of the machining processes.

Cutting thick aluminum plates using laser fusion cutting enhanced by dynamic beam shaping

Cutting thick plates is affected not only by the laser power but also by the cut kerf width and the melt flow dynamics that determine the ejection of the molten material. Employing the same laser beam intensity distribution for various thicknesses is the limiting factor when cutting thicker plates. This paper investigates fiber laser fusion cutting of 25 mm thick aluminum with dynamic beam shaping (DBS). While both static and longitudinal dynamic intensity distributions fail to cut this thickness with a 4 kW laser power, a cut through is achieved using annular and elliptical intensity distributions. However, an improvement of 45% in cutting speed can be achieved using an elliptical intensity distribution compared to an annular one. In order to understand the effect of the beam shape, an infrared thermal camera is used to study lateral heat propagation when using different process parameters. Moreover, to analyze the melt flow when changing the DBS frequency, high-speed imaging is utilized to observe the molten material inside the cut kerf. Finally, the cut edge quality is investigated for different cutting conditions.