Bushing Shape Research Articles

Frictional power loss in journal bearing considering parabolic shape for the bearing edges under misalignment

In recent years, there has been a rising demand for minimizing any power loss in industrial applications due to the direct relation to economic as well as climate considerations. This work investigates the parameters that affect the frictional power loss in journal bearings as they are widely used in such applications. The frictional power loss is calculated considering misalignment conditions in the vertical and horizontal planes with the use of a modified bearing shape. Wide ranges of misalignment and bearing shape parameters are considered in the numerical investigation to study the combined effects of misalignment and bearing shape. It has been found that the misalignment significantly increases the frictional power loss at high operating speed levels. The use of a modified bush shape can play an important role in reducing the frictional power loss as well as, it added further advantages in elevating the lubricant film thickness and reducing the pressure levels. Results show that using a modified bearing shape despite the presence of severe misalignment levels reduces the maximum pressure from 20.30 to 17.94 MPa, increasing the minimum film thickness from 2.66 to 8.21 [Formula: see text] and reducing the fictional power loss from 1179.74 to 1094.41 W.

НОВЫЙ ИНТРОДУЦИРОВАННЫЙ СОРТ ВИНОГРАДА TICKLED PINK

This article presents the varietal study and evaluation of a new introduced grapevine variety Tickled Pink of the USA breeding, obtained as part of the Breeding Program of the University of Arkansas in the conditions of ARRIV&W – Branch of the FSBSI FRARC. An ampelographic description of the variety was made according to the main characteristics. This grapevine cultivar can be distinguished by its seedless berries, similar to Vitis labrusca L. morphological features and taste of berries, small compact clusters, wedge-shaped leaves, medium vigor, and disease and cold-hardiness. The vineyards are not watered, grafted, not covered, the two-armed middle-trunk cordon bush shape, the planting scheme is 3×1.5 m, the pruning is short. Methods generally accepted in viticulture and standard vineyard cultivation technology were used. According to our data, the Tickled Pink variety has an super-early terms of grape ripening (105 days from bud break to full ripeness of berries), small bunches with an average weight of 90.5 g, medium-sized berries with a weight of 2.2 g, seedlessness class II (mass of rudiments 8.7 mg), high resistance to downy mildew, anthracnose and botrytis, medium resistance to powdery mildew. According to the originators, the variety is highly resistant to frost, which we could not confirm due to the lack of critical low temperatures in winter, but it was possible to note the high winter hardiness of the variety. Yield is low, 4.7 t/ha. We believe that the grape cultivar Tickled Pink is not quite suitable for our terroir due to insufficient drought resistance and heat resistance, but it can be recommended for backyard gardening in regions with a cool climate, as well as for use in the breeding of resistant seedless grape varieties.

Анализ изменчивости декоративных признаков рода Dahlia Cav. в однолетней культуре в условиях Московской области

In this paper, the results of the analysis of the variability of quantitative and qualitative decorative features of hybrid dahlia varieties (Dahlia x cultorum Thorsr. et Reis) used in landscaping of the Moscow region are considered. The following varieties are used in the work: Vesioly rebjata mix, Monarch mix, Butterfly Mix, Rumba white, Unwins Bedding Mix, Collarette Dandy Mix. To assess the variability, quantitative characteristics were selected: plant height, leaf size (length, width) and petiole, inflorescence diameter, tongue flower size, abundance of flowering (number of inflorescences per plant), duration of flowering; and qualitative: bush shape, compactness, type, color, glossiness, basket type, basket position relative to leaves, position, color of tongue flowers. The variability of quantitative features was assessed by calculating the coefficients of variation, the variability of qualitative features - by establishing the modalities and frequencies of occurrence. It was found that the studied varieties are the most variable in terms of plant height and the number of inflorescences on the plant, the most stable in terms of inflorescence sizes. Keywords: ANNUAL DAHLIA, BORDER VARIETIES, MORPHOLOGICAL SIGNS, QUANTITATIVE SIGNS, QUALITATIVE SIGNS, COLOR OF INFLORESCENCES, VARIABILITY OF DECORATIVE SIGNS

An Experimental Study on Copper Plates Using Friction Drilling.

Abstract: Friction drilling is a novel hole-making method that can be performed on thin-walled sheets. In recent years of study, the thrust force and torque under numerous process conditions were performed to demonstrate the benefits. In recent years of study, the thrust force and torque under various process conditions were performed to demonstrate the benefits. Our objective is to review the behavior of the material with the use of friction drilling by variation of thickness, Spindle speed, and feed rate. Our objective is to study the behavior of the material with the use of friction drilling by variation of thickness, Spindle speed, and feed rate. The friction between a rapid rotating conical tool and a sheet metal workpiece generates heat to soften and displace the metal to form a whole. Friction drilling is a non-traditional hole-making process in which a conical rotating tool is applied to penetrate the workpiece and make the outlet in a single step, without generating chips. the process relies on the heat generated thanks to the resistance force between tool and workpiece, to soften, penetrate and deform the work material into a bushing shape. Generally, friction drilling is applied to thin-walled materials owing to increasing connection length and clamping strength. The generated resistance heat cause softening piece of work material, increase its ductility, and providing it to flow, that extruded onto both the front and back sides of the holes. Keywords: Friction Drilling, Conical Tool, Material Displace, Temperature, Hardness & Thickness.

Highlights of Non-traditional friction drilling process A review

Frictions drilling a hole making process were hole is produced in sheet metal lesser than 4 mm thickness. In 90% of the manufacturing industry adopts drilling process. Apart from traditional methods non-traditional method of hole making process is adopted for producing hole in sheet metal. Friction drilling is a chip less hole making method, were chips formed as bosh and bush into front and bottom of the plate. Bushing height is produced three times the thickness of work piece thickness. The tool is plunged into the hole due to the heat generated in-between tool and work piece. The temperature developed in the tool and material is very high, due to this the chances of getting damage in tool and material is also high. In this review the highlights of friction drilling process has been covered. The key factors is the way of hole making process. Frictions drilling a chip less method, metal melt to form as a bushing shape. To avoid material as well as tool damages factors like input parameter, material thickness, adopting coating thickness etc. In the observation section the key issues are highlighted and in further how the friction drilling tool can be designed to avoid material damages.

Устойчивый к засухе сорт сои Волгоградка 1

The constant intensification of global soybean production is closely related to the breeding and seed production of this crop. Therefore, the research focused on the development of new varieties is quite relevant. The long-term screening at various agricultural backgrounds in dry and relatively favorable years helped identify a high drought resistance of soybean line 214, named Volgogradka 1, which is included in the State Register of varieties approved for use in the Lower Volga region (Russia) and Ural region (Kazakhstan). The variety is of medium-early 33 ripening, tall with a semi-determinant type of growth and a semi-compressed bush shape. It is characterized by high resistance to the main soybean diseases, such as Septoria blight, bacteriosis, mosaic compared to the standard varieties. It develops a high yield of biomass - from 3.29 to 10 t/ha in dry matter, which is higher than the standards (3.58-6.39 t/ha), so it is ideal for use on monofodder, it is a good predecessor that enriches the soil with nitrogen. Due to the high linear growth and, consequently, to the root system deeply developed in the soil, the semi-determinant type of development, the agrocenosis of the variety Volgogradka 1 can effectively use a small amount of precipitation during the growth season and at a low hydrothermal coefficient of the territory. The variety Volgogradka 1 is able to develop from 2.51 to 3.85 t/ha of grain in crops with irrigation due to its increased branching, tallness, resistance to lodging of the stem and a highly branched root system, which significantly exceeds the standard varieties in this indicator. The expansion of Volgogradka 1 sowings under irrigation conditions will increase the yield of soybean and to accelerate its import substitution.

Prediction of Nonlinear Stiffness of Automotive Bushings by Artificial Neural Network Models Trained by Data from Finite Element Analysis

Due to the nonlinear behavior of rubber for bushings, the prediction of mechanical properties of the bushing requires nonlinear finite element analysis (FEA) techniques and a lot of computation time. Therefore, we propose a method to efficiently predict the stiffness of bushings using an Artificial Neural Network (ANN) model trained by data from FEA. First, FEA was performed for the designed 3D and 2D bushing models. Based on the relationship between the bushing shape design variables and the stiffness values predicted by the FEA, we trained the Multilayer Perceptron (MLP) and the Convolutional Neural Network (CNN) models among the ANN models. Given the shape design variables of the bushing model, the stiffness values were predicted by the MLP model. Given the image of the bushing model, the stiffness values were predicted by the CNN model. The stiffness prediction results showed that both models can be used to predict the stiffness of the bushings, and that the CNN model is slightly more accurate than the MLP model. In particular, it is expected that designers can easily estimate stiffness values by taking advantage of the CNN model which can use photographic images of real parts as inputs.

3D point cloud data to quantitatively characterize size and shape of shrub crops

Size and shape are important properties of shrub crops such as blueberries, and they can be particularly useful for evaluating bush architecture suited to mechanical harvesting. The overall goal of this study was to develop a 3D imaging approach to measure size-related traits and bush shape that are relevant to mechanical harvesting. 3D point clouds were acquired for 367 bushes from five genotype groups. Point cloud data were preprocessed to obtain clean bush points for characterizing bush architecture, including bush morphology (height, width, and volume), crown size, and shape descriptors (path curve λ and five shape indices). One-dimensional traits (height, width, and crown size) had high correlations (R2 = 0.88–0.95) between proposed method and manual measurements, whereas bush volume showed relatively lower correlations (R2 = 0.78–0.85). These correlations suggested that the present approach was accurate in measuring one-dimensional size traits and acceptable in estimating three-dimensional bush volume. Statistical results demonstrated that the five genotype groups were statistically different in crown size and bush shape. The differences matched with human evaluation regarding optimal bush architecture for mechanical harvesting. In particular, a visualization tool could be generated using crown size and path curve λ, which showed great potential of determining bush architecture suitable for mechanical harvesting quickly. Therefore, the processing pipeline of 3D point cloud data presented in this study is an effective tool for blueberry breeding programs (in particular for mechanical harvesting) and farm management.

Experimental investigation on friction drilling of stainless steel AISI 304

Friction drilling is an unexplored manufacturing process to produce holes in thin-walled sheet metals. In this study, the effects of process parameters in friction drilling of austenite stainless steel investigated experimentally and statistically. It was confirmed, sufficient heat generation, which cause to better bushing shape and height, acceptable drilled-hole diameter and lowest roundness error result from low spindle speed and high feed rate. It was obtained, although effect of feed rate on hole-wall thickness was negligible; spindle speed has significant effect on that which is inverse from spindle speed effect on bushing height. Moreover, micro-hardness reduced gradually away from the drilled-hole edge. Observing on tool shape and wear damage using optical microscope and scanning electron microscope quantifies effects of spindle speed and feed rate on tool performance and tool wear characteristics. Results indicate that better performance of drilling tool obtained from lower spindle speed and high feed rate.

Experimental investigation on friction drilling of stainless steel AISI 304

Friction drilling is an unexplored manufacturing process to produce holes in thin-walled sheet metals. In this study, the effects of process parameters in friction drilling of austenite stainless steel investigated experimentally and statistically. It was confirmed, sufficient heat generation, which cause to better bushing shape and height, acceptable drilled-hole diameter and lowest roundness error result from low spindle speed and high feed rate. It was obtained, although effect of feed rate on hole-wall thickness was negligible; spindle speed has significant effect on that which is inverse from spindle speed effect on bushing height. Moreover, micro-hardness reduced gradually away from the drilled-hole edge. Observing on tool shape and wear damage using optical microscope and scanning electron microscope quantifies effects of spindle speed and feed rate on tool performance and tool wear characteristics. Results indicate that better performance of drilling tool obtained from lower spindle speed and high feed rate.

An Experimental Investigation on Bushing Geometrical Properties and Density in Thermal Frictional Drilling

In thermal friction drilling (TFD) operations, the geometrical dimensions of bushing shape, height and wall thickness are the most vital consequences, since these increase the connecting length and strength. In this paper, AA7075-T651 aluminum alloys with 2, 4, 6, 8, and 10 mm thicknesses were drilled with the TFD process in order to investigate density, volume ratio, and height and wall thickness of the bushings. The experiments were conducted at constant spindle speed and feed rate conditions by using High Speed Steel (HSS) conical tools of 5, 10, 15, and 20 mm in diameter. It was experimentally found that the bushing height and the wall thickness had a tendency to increase linearly with the increase in both material thickness and tool diameter. The effect of tool diameter was found to have more influence on the measurable values than the thickness of the drilled material. The density of the bushing changed trivially. Approximately 70–75 percent of the evacuated material formed the bushing shape in TFD operations.

Influence of rotational speed on mechanical features of thermally drilled holes in dual-phase steel

Thermal drilling is a novel chipless sheet metal drilling process that uses a rotating thermal drill tool to pierce and form a bushing shape hole. In this work, thermal drilling process is successfully employed to drill the DP 600 grade–type galvanized steel with a thickness of 2 mm. The influence of different spindle rotational speeds such as 1600, 2000 and 2400 r/min on the formation of bushing height, surface roughness, microhardness and microstructure of the thermal-drilled holes are investigated in detail. Process parameters such as feed rate, thermal drill angle and workpiece thickness were held constant in order to explore the influence of rotational speed on the quality characteristics of the thermal drilling process. It has been found that the bushing height was improved with increasing of rotational speed, but the petal formation at the outer edge of the bush is decreased. Surface roughness tests indicate that the better surface quality drilled hole could be obtained at the highest rotational speed of 2400 r/min. The microstructural investigation confirmed that a new result of Lüders band marks was formed inside the thermal-drilled holes because high thermal stress and yielding of galvanized steel material.

3D phenotyping and QTL analysis of a complex character: rose bush architecture

Plant shape, and thereby plant architecture, is a major component of the visual quality of ornamental plants. We have been developing a new method for analyzing the entire plant architecture by 3D digitalization that allows an almost exhaustive description of rose bush architecture and generates a large number of variables, many of them inaccessible manually. We carried out a QTL analysis using this original phenotyping method. In order to evaluate a broader allelic variability as well as the effect of the genetic background on QTL detection, we used two connected, segregating, recurrent blooming populations. The number of QTLs per variable varied from three for the number of determined axes (NbDetA) to seven for the branching angle of order 2 long axes (AngLA2), the two populations taken together. Five new QTLs, located on the linkage groups (LGs) 2, 6, and 7, were detected for the branching angle of axes, and the QTL located on LG7 co-localized with RhBRC1, a branching repressor. Branching and stem elongation QTLs also co-located with RhBRC1, suggesting its pleiotropic nature. Year-specific QTLs were also revealed, that explained the genotype × year interactions observed for the number of order 3 short axes (NbSA3) and AngLA2 from a genetic point of view. We also evidenced an effect of the genetic background on QTL detection. This new knowledge should help to better reason the genetic improvement programs for rose bush architecture and, therefore, rose bush shape.

An Experimental Investigation of the Effect of Depth and Diameter of Pre-drilling on Friction Drilling of A7075-T651 Alloy

Friction drilling is a non-traditional drilling process, in which specimens are drilled by means of frictional heat, which is obtained from friction effect in between rotating conical tool and workpiece area. The main purpose of current study was to investigate the effect of pre-drilling depth and diameter on the bushing shape, initial deformation and frictional heat in friction drilling of A7075-T651 aluminum alloy, known as a brittle material. Results showed that the effect of pre-drilling depended on the geometrical dimensions of the tip of the tool. The initial deformation was reduced, frictional heat was generated regularly and bushing shape was in the form of cylindrical with less cracks and petal formation in conditions predrilling diameter close to the end diameter of the tip of the tool and pre-drilling depths bigger than its length. The highest temperature was recorded at 3000 rpm spindle speed and 40 mm/min feed rate.

Investigate the Effect of Pre-drilling in Friction Drilling of A7075-T651

Friction drilling is a non-traditional hole achieving method that is a clean, chip-less process, which is called thermal drilling, form drilling, flow drilling, and friction stir drilling. In this study pre-drilling friction drilling was investigated for improving the bushing shape of A7075-T651, which is a brittle cast material. During the process, surface roughness and bushing shapes were analyzed and generated frictional heat was measured by the virtue of thermocouples. Experiments were carried out to 4 mm and 6 mm in thicknesses of A7075-T651 aluminum alloy at 1200, 1800, 2400, 3000, and 3600 rpm spindle speeds, 20, 40, 60, 80, and 100 mm/min feed rates with using high-speed steel rotating conical tool, whose diameter is 8 mm. Consequently, the bushing shapes were advanced without cracks and petal formation in pre-drilling Friction drilling in comparison with without pre-drilling process. With increasing pre-drilled hole diameter the generated frictional heat was decreased. The achieved temperature was realized to be 1/2–1/3 of the melting temperature of the workpiece. Surface roughness values were decreased with decreasing or increasing both spindle speed and feed rate correspondingly.

Investigate the effect of tool conical angle on the bushing height, wall thickness and forming in friction drilling of A7075-T651 aluminum alloy

Friction drilling process is a non-traditional hole drilling process formed by thermal friction having the most important features such as no pollution, short machining time and long tool life. In this process conical tool is used to generate heat by friction to soften and generate a thin workpiece and create a bushing without generating chips. In this friction drilling experimental study, the selected spindle speeds were 2400 rpm, 3600 rpm, and 4800 rpm, feed rates were 50 mm/min, 75 mm/min, and 100 mm/min and tool material was HSS tool with 24°, 36°, and 48° conical angles, 8 mm, 10 mm, and 12 mm cylindrical region diameters and 16 mm tool cylindrical region lengths. The specimens were A7075-T651 with thickness of 4 mm, and 6 mm. The effect of tool conical angle on the bushing height, bushing wall thickness, and bushing shape were analyzed. It was seen that for 4 mm and 6 mm materials thicknesses, according to the bushing height, the most optimum tool conical angle was 24° for all diameters. For 4 mm material thickness according to the bushing wall thickness 48° was the most optimum conical angle in friction drilling 8 mm diameter, 24° for friction drilling 10 mm and 12 mm diameters. The most optimum tool conical angle was 36° for 8 mm diameter, 24° for 10 mm and 12 mm diameters. With decreasing tool conical angle the bushing height was increased and bushing wall thickness was decreased. In the conditional low tool conical angles the softened material flow in the direction of tool motion in friction drilling, thus bushing height increased and wall thickness decreased. With increasing both tool conical angle and spindle speed the cracks in obtained bushing were advanced and the shape of bushing formed as petal. But with increasing feed rate the bushings shapes were not changed.

Investigate the Surface Roughness and Bushing Shape in Friction Drilling Of A7075-T651 and St 37 Steel

Due to the beneficial of the bushing form, the connection length and clamping strength is increased in friction drilling of thin-walled cast materials. In this experimental study 2400, 3600, and 4800 rpm spindle speeds, 50, 75, and 100 mm/min feed rates, 240 , 360 , and 480 tool conical angles were selected. 2, 4, and 6 mm thicknesses of A7075-T651 aluminium alloys and St 37 steel materials were drilled with using 10 mm diameter HSS (High Speed Steel) and WC (Tungsten Carbide) rotating conical tools which have 16 mm cylindrical region length. I was analysed the surface roughness, bushing height and bushing sheet thickness according to the spindle speed, feed rate, tool conical angle, workpiece material thickness, both workpiece and tool material types parameters. Consequently it was discovered that in friction drilling of 2 mm thickness A7075-T651 aluminium alloy, the bushing was formed as petal shape, which limited providing connection length and clamping strength owing to the brittleness of the material. In friction drilling of brittle materials, there were a lot of cracks generated on the bushing shape. The minimum surface roughness values were obtained at 3600 rpm spindle speed and 75 mm/min feed rate conditions friction drilling of St 37 steel material. The surface roughness values of A7075-T651 aluminium alloys were higher than St 37 steel materials. In conditions decreasing the spindle speeds, tool conical angles, and increasing feed rates, the bushing height was increased and bushing wall thickness was decreased.

Effect of tree channel conductivity on electrical tree shape and breakdown in XLPE cable insulation samples

The results of an investigation into electrical tree growth in XLPE cable insulation using an embedded needle electrode are reported for a range of voltages from 9 kV rms to 27 kV rms. The partial discharge (PD) activity and tree structures were measured simultaneously throughout the tree growth and the trees were recorded from initiation up to and including the final runaway stage. A multifractal analysis was also performed on the tree structures as they propagated, and it was found that their fractal dimension increased and the distribution of embedded structures changed as small side channels were added to the tree as it grew. At 11 kV rms only branch trees were found and only bush (bush-branch) trees at higher voltages, but at 9 kV rms trees of three different shapes were formed. Observation of the tree shapes at 9 kV rms under reflected light followed by a detailed analysis using con-focal Raman spectroscopy, showed that the stagnated and branch-pine (monkey puzzle) tree shapes were due to the formation of a conducting graphitic deposit upon the walls on tree branches in the region of the needle electrode. This was not present in the branch trees produced at 9 kV rms. A simple scheme is presented for the formation of branch-pine trees and their corresponding PD activity based on the concept of conducting branch generation. The trees produced at 13 kV rms and above have a bush shape, which converts into a bush branch shape when a runaway branch grows from their periphery. This is shown to happen when the field at the bush tree periphery exceeded a voltage independent critical value, which was estimated to be 100 MV/m. The consequence of this result for the initiation of the runaway stage in branch trees is commented upon.

Variability of Some Characters of the Pepper Cultivar Ileana (Capsicum annuum L.)

The new pepper cultivar ‘Ileana’ (Capsicum annuum L.), obtained at Fruit Research Station Cluj, Romania and homologated in 2007 (Jidavu et al., 2007). The new cultivar was the result of one complex hybridization: ♀{[♀Cj 7-82 (♀Cj 5-64) x ♂Alma)] x ♂Compact}F5 x ♂Feher ozon, followed by the repeated individual selection. ‘Ileana’ was cultivated in the open field, in order to initiated conservative selection for the maintain authenticity and the biological purity. The principal characteristics of the plants and fruits were analyzed and coefficients of variability were computed. Variability coefficients of plant characteristics (height, diameter and bush shape) had medium values (CV%: 10.5-14.7). CV% of fruit’s trait varied from 8.6% (diameter) to 24.0% (number of fruits per plant). The uniformity of the plant and fruit characters, could be considering quite homogeneous, even if the productivity characters were registered with a variability denoting influence of the environment. Due their favorable peculiarities including fruits quality, the new pepper cultivar ‘Ileana’ is recommended for culture.

Experimental and Numerical Analysis of the Friction Drilling Process

Friction drilling is a nontraditional hole-making process. A rotating conical tool is applied to penetrate a hole and create a bushing in a single step without generating chips. Friction drilling relies on the heat generated from the frictional force between the tool and sheet metal workpiece to soften, penetrate, and deform the work-material into a bushing shape. The mechanical and thermal aspects of friction drilling are studied in this research. Under the constant tool feed rate, the experimentally measured thrust force and torque were analyzed. An infrared camera is applied to measure the temperature of the tool and workpiece. Two models are developed for friction drilling. One is the thermal finite element model to predict the distance of tool travel before the workpiece reaches the 250°C threshold temperature that is detectable by an infrared camera. Another is a force model to predict the thrust force and torque in friction drilling based on the measured temperature, material properties, and estimated area of contact. The results of this study are used to identify research needs and build the foundation for future friction drilling process optimization.