Papers by Keyword: Depth of Cut

Abstract: In machining process, surface roughness and material removal rate have a vital importance since they affect mass production, consumption of energy, force, and tool life and product quality. In this study, Taguchi-Grey Relation Method (TGRM) is applied to AISI 1040 mild steels in the hardened form when machined with ceramic inserts using response surface methodology for multi-objective optimization. Grey-Relation Method and Pareto chart reveal that feed rate, depth of cut, speed besides square effect of speed/feed rate are effective parameters on the response. Among all eighteen experiments, trial twelfth provides the best multi-performance characteristics while the first experiment shows the worst performance. Optimal levels are determined at higher speed, higher feed rate associated with higher depth of cut. It is concluded that quadratic regression model and reduced quadratic regression model are developed. The correlation coefficients range from 98.3% to 96.89%, respectively. As a result, TGRM has an efficient to provide a good modelling in combination of surface roughness and metal removal rate.

Abstract: The properties and the performance of Thermally Stable Diamond Composite (TSDC) directly affect the applications of TSDC in engineering. The failure risk of the TSDC cutting tips during a cutting process is affected by many factors, including the Depth of Cut (DOC) of the pick with the TSDC tip. The DOC is an important indicator in mining and construction industries because it directly affects productivity and pick failures. In existing studies, DOC is usually treated as a deterministic variable. However, due to the drum vibration during a cutting process, the DOC during production often varies randomly around its nominal value. This study investigates the influence of the randomly varied DOC on the performance and failure characteristics of TSDC tipped rock cutting picks, in combination with random resultant angle. Monte Carlo simulation method is applied. It is found that the variation in DOC can have considerable influence on the failure characteristics of the TSDC cutting tips, although this influence is affected by the resultant angle and attack angle. This characteristic is important for optimising the design and application of the TSDC tipped picks.

Abstract: This study evaluates the impacts of machining parameters on the milling of general-purpose poly (methyl methacrylate) (PMMA) with respect to cutting point temperature, maximum machining temperature, and surface roughness. The machining parameters used in the analysis are spindle speed (rpm), depth of cut (mm), and feed rate (mm/min). The extreme ranges of the machining parameters for the material are obtained from trial experiments. From these experiments, four values of each parameter are adopted. This yields 12 experiments, which are divided into three sets. In the first set of experiments, the depth of cut and feed rate are held constant at 0.2 mm and 25 mm/min, while the spindle speed is varied from 1000 rpm to 4000 rpm. In the second set of experiments, the spindle speed and feed rate are held constant at 1000 rpm and 25 mm/min, respectively, while the depth of cut is varied from 0.2 mm to 1.1 mm. In the last set of experiments, the spindle speed and depth of cut are held constant at 1000 rpm and 0.2 mm, respectively, as the feed rate is varied from 25 mm/min to 100 mm/min. Thermal images are obtained during milling, where the cutting point and maximum machining temperatures are obtained. The milled surfaces are then investigated for surface roughness. The chips are also collected from each experiment and used in conducting chip morphology. From the results, it is observed that to obtain the least temperatures and best surface quality, the least machining parameters should be chosen. These parameters are identified as 1000 rpm, 0.2 mm, and 25 mm/min for the spindle speed, depth of cut, and feed rate, respectively. An increase in spindle speed seems to increase the milling temperatures and surface roughness, which is attributed to the reducing chip thickness. An increase in the depth of cut does not affect the generation of chips, and the thickness is relatively constant. However, an increase in milling feed increases the chip thickness, which increases the surface roughness.

Abstract: The purpose of this work is to increase the productivity and accuracy of processing long-length parts of the "shaft" type on CNC machines. Based on the analysis of existing methods for improving the accuracy of processing long shafts on CNC machines, a new method for controlling the spatial error of processing long shafts by changing the processing modes was proposed. The proposed method allows, by changing the processing modes, namely feed, to reduce the radial component of the cutting force and reduce the amount of deflection when machining parts on CNC machines. A technical and economic analysis and justification of scientific research was carried out. The economic effect of the proposed method.

Abstract: Stainless Steels are possessing fabrication flexibility, high hardness, durability, low maintenance, high strength and resistance to heat and corrosion. This alloy steel is extensively used in various engineering applications. Some of the conventional machining techniques results in loss of original properties of stainless steel work material and makes it to behave like ordinary material within the machined surface. Machining of Stainless steels is more challenging due to its high alloying content. Problems such as application of huge coolant supply and poor chip breaking while machining, work hardening in work material, use of cutting tools with varying tool signature, results in enhanced production cost and time. Further, it is important to ensure that there is no machine tool-cutting tool vibration leading to edge chipping of cutting tool. To avoid all these problems, Abrasive water jet machining (AWJM) is used. This paper presents the machining capabilities of AWJ on Stainless Steel304. Influence of dynamic input parameters such as jet pressure, speed of traverse and abrasive flow rate on the depth of cut is investigated. An empirical model is proposed for depth of cut and an error analysis is done with measured and modeled values of depth of cut. It was found that traverse speed influences more than other parameters. SEM images indicated smooth surface at entrance and waviness at exit side. The model proposed predicts the depth of cut more or less accurately.

Abstract: Quality of the product is the major concern in manufacturing industries from customers as well as producers point of view. There are number of factors in the product such as surface condition, height, weight, length, width etc., which may be consider for the measurement of the quality. Surface roughness and Metal Removal Rate (MRR) are the two main outcomes on which numerous researchers have applied different approaches for several years to get optimum results. In this study, Taguchi Method is applied for getting optimum parameters settings for Surface roughness and Metal Removal Rate (MRR) in case of turning AlMg3 (AA5754) in CNC Lathe machine, which is an aluminum alloy having diameter 20 mm and length 100 mm. The three parameters i.e. spindle speed, feed rate and depth of cut with 3 levels are taken as the process variables and the working ranges of these parameters for conducting experiments are selected based on Taguchi’s L9 Orthogonal Array (OA) design. To analyze the significant process parameters; main effect plots for data means and for S/N ratio are generated using Minitab statistical software.

Abstract: Drilling and lateral cutting are two cutting modes used by roadheaders in rock cutting. Accurate estimation of the depth of cut (DOC) of the cutterhead of a roadheader is critical for improving the performance and reliabilityofthe roadheader. Some models have been developed for calculating the DOC of a cutterhead in lateral cutting mode. However, an effective method for computing the DOC of a cutterhead in drilling mode is yet to be developed. As thecharacteristicsof the drilling process are significantly different from those of the lateral cutting process, the models developed for calculating the DOC in lateral cutting mode are not suitable for estimating the DOC ofacutterhead indrilling mode. In this study, a quantitative analysis of the DOC in drilling mode is developed via an investigation ofrock breakout patterns. The results show that in anydrilling case, the DOC of the picks on the cylindrical and conical parts of a cutterhead cannot be calculated by using the advance distance per revolution of the cutterhead. The DOC of a pick is affected by the difference between the cutting radii of the pick and its adjacent picks. It is also affected by the interaction between cutting lines. While the distance between two cutting lines in lateral cutting mode is fixed, the distance betweentwo cutting lines inthe drilling mode can vary. The outcome of the studycan help optimisation of cutterhead design and operation.

Abstract: This paper presents a mathematical model of the maximum thickness and the chip area for the processes of cylindrical and profile milling of various materials, including wood. The analytical dependences connecting the geometry of the shear layer with the elements of the milling mode and cutter design parameters are determined. Also, a model of the volume of material removed from the surface of the workpiece during the milling profile is presented. The comparative calculations of the previously known models and the models developed by the author were done. It was found that the models of the geometric parameters of cutting layer presented in the article are adequate and can be used to calculate the energy performance of the wood milling process with cylindrical and shaping cutters. These models are suitable for use in the calculations of the processing parameters for a wide range of material: metals, wood, plastic, glass and others.

Abstract: The selection of optimum machining parameters plays a significant role for the quality characteristics of products and its costs for grinding. This study describes the optimization of the grinding process for an optimal parametric combination to yield a surface roughness using the Taguchi method. An orthogonal array and analysis of variance are employed to investigate the effects of cutting environment (A), depth of cut (B) and feed rate (C) on the surface roughness characteristics of mold steels. Confirmation experiments were conducted to verify the optimal testing parameters. The experimental results indicated that the surface finish decreased with cutting-fluid and depth of cut, but decreased with increasing feed rate. It is revealed that the cutting fluid environment had highest physical as well as statistical influence on the surface roughness (71.38%), followed by depth of cut (25.54%), but the least effect was exhibited by feed rate (1.62%).

Abstract: Modern industry increasingly deploys waterjet machining of materials, a technology based on extremely complex and at times difficult to explain phenomena. Aimed at elucidating certain aspects of the cutting mechanics of waterjet machining, the paper presents the calculation and discusses the penetration depth of the water drops into the part material and the necessary working pressures.