Determination of Turning Knife Thermal Stress during Longitudinal Turning

2016 ◽  
Vol 821 ◽  
pp. 649-654
Author(s):  
Marek Stránský ◽  
Jaroslav Horský
Keyword(s):  
Machine Tools ◽  
Inverse Relationship ◽  
Work Piece ◽  
Machined Surface ◽  
One Dimensional ◽  
Friction Heat ◽  
Longitudinal Turning ◽  
New Machine

A turning knife contacts a work piece during turning. Due to friction, heat is produced proportionally to the turning speed. The resulting temperature influences the quality of the machined surface and wear of the knife. Thus, new machine tools must be developed that minimize the production of unwanted heat. To accomplish this task, a new experimental knife was prepared with thermocouples both built into it and welded to its surface. The measurement process was supplemented by thermovision. Heat flux and surface temperatures were computed from subsurface data using a one-dimensional inverse relationship. The detailed temperature distribution on the surface of the turning knife was determined using a combination of these methods.

Identification of Residual Stress in the Production of Molding Tools by Turn-Milling Technology

2017 ◽  
Vol 14 (1) ◽  
pp. 14-16
Author(s):  
Michal Šajgalík ◽  
Tomáš Pavlusík ◽  
Jozef Pilc ◽  
Matej Mikloš ◽  
Igor Daniš ◽  
...  
Keyword(s):  
Residual Stress ◽  
Machine Tools ◽  
Tool Path ◽  
New Technology ◽  
High Surface ◽  
Heavy Duty ◽  
Machined Surface ◽  
Turn Milling ◽  
New Machine

Abstract This article describes how to plan the tool path and analyze the surface of the machined part by working simultaneously on two basic operations such as milling and turning. New machine tools allow parallel processing of both multi-axis tools at the same time, it is a production technology in which the workpiece and the tool are simultaneously rotating. This relatively new turnmilling technology could be an alternative to increasing productivity in many applications. Especially in cases involving heavy-duty materials or large diameters of machined surface. The aim of this study is to explore this new technology, especially with regard to the increased precision and quality of the surface of the workpiece. Experimental results show that the combination of these two operations is suitable for precise machining of rotationally symmetrical workpieces with high surface finish.

Experimental and Numerical Study of the Cutting Temperature during the Turning of the C45 Steel

2016 ◽  
Vol 823 ◽  
pp. 507-512
Author(s):  
Mourad Abdelkrim ◽  
Mourad Brioua ◽  
Abderrahim Belloufi ◽  
Abdelhafid Gherfi
Keyword(s):  
Numerical Study ◽  
Digital Simulation ◽  
Cutting Temperature ◽  
Medium Carbon Steel ◽  
Simulation Software ◽  
Interface Temperature ◽  
Work Piece ◽  
Turning Process

In machining operation, the quality of surface finish is an important requirement for many turned work pieces. cutting temperature is one of the most important parameters in determining the cutting performance and tool life. the objective for this work is to estimate the cutting temperature in 3D model on tool-chip interface and the interface temperature during turning process, using the digital simulation software COMSOL Multiphysics.The tool–chip interface temperature results obtained from experimental results by using C45 medium carbon steel work piece with natural contact tools, without the application of cooling and lubricating agents and a K type thermocouple technique was used for estimating cutting temperatures in a turning operation.This procedure facilitates the determination of the temperature at tool-chip interface in dry turning process, which is still a challenge for existing experimental and numerical methods.

The Processing of the Profile Surface of the Work-Pieces, Characterized by Low Rigidity

2020 ◽  
Vol 299 ◽  
pp. 852-860
Author(s):  
Anatoly A. Fomin ◽  
Vladimir G. Gusev ◽  
Nail F. Timerbaev
Keyword(s):  
Mechanical Characteristics ◽  
Flexural Rigidity ◽  
Geometric Error ◽  
Technological System ◽  
Design Parameters ◽  
Work Piece ◽  
Machined Surface ◽  
Spindle Unit ◽  
Physical And Mechanical Characteristics

This work indicates that the prediction of the geometric indicators of the quality of the machined surface in the design of technological operations for milling a profile surface of work-pieces with low rigidity is possible, on the basis of an analysis of the elastic displacements of the technological system elements, the flexural rigidity of the work-piece as a function of its initial dimensions, the locating chart and the physical and mechanical characteristics of the material being processed. The article describes the characteristics of the elements of the technological system for the profile milling of work-pieces of low rigidity; The analytical dependencies linking the elastic displacements of the work-piece during the processing of various wood species with elements of the milling mode and the design parameters of the mill are given. Extreme total elastic displacements of the technological system during the cutting process are determined. Mathematical models of the maximum geometric error of the machined surface, as a function of the work-piece's flexural rigidity and the spindle unit, are established. Based on the results of the analysis, recommendations for improving the accuracy of the product were developed.

Pengukuran Kesilindrisan Hasil Proses Pemotongan Mesin Bubut Untuk Mengetahui Kemampuan Mesin Menghasilkan Suatu Produk

2019 ◽  
Vol 10 (02) ◽  
pp. 9-13
Author(s):  
Ariyanto Ariyanto ◽  
Husman Husman
Keyword(s):  
Machine Tools ◽  
Skills Training ◽  
Machining Process ◽  
Machine Repair ◽  
Geometric Shapes ◽  
New Machine

The ability of machine tools to produce a product of good quality is needed by the industrial industry that exists today. Industrial industries that use machine tools are not only industries that produce products in the form of a tool or machine, machine tools are also widely used by industries or institutions that serve machine repair and providers of skills training. The quality of the machine measured using the geometry of the workpiece resulting from the machining process can be in the form of roundness, cylindrecity, tapers and other geometric shapes. The use of machine tools that continue for several years can result in a decrease in the ability of the machine to produce a product. The use of a long horizontal doall lt13 lathe will produce a form of workpiece cylindricity that is not the same as the condition of the the new machine tools, therefore testing activities are carried out by cutting the machine and seeing what the cylindrical value of the specimen is capable of achieving . From the results of the testing that has been carried out on a horizontal lathe as many as eight units, the values of cylindrical difference are different for each machine. The highest value of cylindricity is produced by lathes with machine number 8 and the smallest cylindrical value produced by lathes with machine number 3. The greatest tolerance is achieved in the quality of IT (international tolerance) 11 tolerance and the lowest is achieved in IT tolerance quality 10.

Investigation of Control Methods of Chatter Vibration Based on Analysis of End-Milling Chatter Mark

2016 ◽  
Vol 1136 ◽  
pp. 639-644 ◽  
Author(s):  
Ryosuke Shiota ◽  
Tatsuya Furuki ◽  
Toshiki Hirogaki ◽  
Eiichi Aoyama
Keyword(s):  
Machine Tools ◽  
Cutting Tool ◽  
Natural Frequencies ◽  
End Milling ◽  
Relative Displacement ◽  
Surface Pattern ◽  
Work Piece ◽  
Chatter Vibration ◽  
Machined Surface ◽  
Milling Chatter

Chatter vibration generated by coupling a work-piece, machine tools, and cutting tool is a serious problem for engineers. A regular pattern forms the machined surface when chatter vibration occurs. There must be a direct relationship between the relative displacement and machined surface. We propose a method for controlling chatter vibration of end-milling from a machined surface. Hammering tests were first carried out to determine the natural frequencies of machine tools and the tool system, which are likely to be the cause of vibration. We also propose a technique of applying reverse analysis to end-milling surfaces. The machined surface is assumed to include an essential index to easily control chatter vibration at the factory. We found that chatter vibration occurs near the frequency of the cutting tool, tool holder, and their coupling, not at the natural frequency, and the chatter vibration frequency can be calculated by analyzing the surface pattern and cutting conditions. Moreover, the proposed method was effective in analyzing chatter vibrations including more than two kinds of natural frequencies at the same time.

scholarly journals The Assessment of Cross Machine Openness Uniformity of a Fiber Feed Matt

2000 ◽  
Vol os-9 (4) ◽  
pp. 1558925000OS-90
Author(s):  
Ayad Oumera ◽  
Abdelfattah M. Seyam ◽  
William Oxenham
Keyword(s):  
Thickness Measurement ◽  
One Dimensional ◽  
Line Measurement ◽  
On Line ◽  
Compression Data ◽  
The One ◽  
Compression Characteristics ◽  
Input Level

The one-dimensional characteristic of yarn has resulted in very little attention being given to the uniformity of carded web in the cross machine direction. The development of nonwovens has prompted researchers to reconsider the importance of cross machine uniformity in determining the total uniformity of the carded web. It is therefore important to develop manual and online techniques to quantify cross machine uniformity at both the input and output of the card. At the card input, uniformity is taken as representing both mass and openness characteristics of the feed matt. While at the card output, there are many available techniques that allow the on-line measurement of the mass uniformity of the carded web, determination of uniformity at the input level is more difficult. The approach that was taken was to use an off-line technique to find the mass and openness of the feed matt at different locations across the card. While traditionally mass as a property has been given a lot of importance, much less attention has been given to the concept of openness. This is due in part to the difficulty in quantifying openness. Openness is believed to have great significance in determining the overall quality of the carded web, especially with regard to the formation of neps. In order to make the concept of openness more clear, it was found necessary to develop a way of quantifying it. This was done by performing a compression test on the feed matt, and then fitting the compression data with an exponential curve. The coefficient of the exponent was used to represent openness. This approach was used to find the effect of the feed roller (pin type) on cross machine uniformity. It was found that the squeezing of the feed roller did not have an effect in redistributing the mass of the feed matt, but did have an effect in changing the openness of the feed matt. Because of the difficulty involved in the handling of the feed matt, a newly developed technique is suggested to characterize openness. While this method still relies on the compression characteristics of the feed matt, it is more appropriate because it is performed on-line. Preliminary results are reported. It was found that thickness measurement under carefully selected pressure value could be used to characterize openness precisely.

Study on Minimum Quantity Lubrication Systems in Cooling of Machining Processes

2015 ◽  
Vol 809-810 ◽  
pp. 1022-1027 ◽  
Author(s):  
Ionel Olaru ◽  
Dragoş Iulian Nedelcu
Keyword(s):  
Machine Tools ◽  
Cutting Tool ◽  
Minimum Quantity Lubrication ◽  
Positive Influence ◽  
Nozzle Geometry ◽  
Machining Processes ◽  
Machined Surface ◽  
Cooling Systems ◽  
Cutting Operation

The cooling systems on machine tools are particularly important; these have a positive influence on the cutting operation and the quality of machined surface. A particular importance represent finding an optimal correlation between the lubricant and coolant used, the material to be processed, processing method and the cutting regime. A high temperature in the working area over a certain value allowable can be harmful in terms of both the resulted surface quality and repercussions on the life of the cutting tool. The parameters of the cooling-lubricating fluid flow can be influenced by the nature of the fluid or fluids, or the nozzle geometry used, which generally has a convergent-divergent geometry in order to achieve a better dispersion of the coolant/lubricant on the area to be machined.

scholarly journals COMPUTER IMPLEMENTATION OF RECURSION ALGORITHM DETERMINATION OF THREAD TENSION DURING FORMATION OF MULTILAYER FABRICS FROM POLYETHYLENE THREADS

2021 ◽  
Vol 297 (3) ◽  
pp. 204-207
Author(s):  
VOLODYMYR SHCHERBAN ◽  
JULY MAKARENKO ◽  
OKSANA KOLISKO ◽  
LUDMILA HALAVSKA ◽  
YURYJ SHCHERBAN ◽  
...  
Keyword(s):  
Human Body ◽  
Machine Tools ◽  
Physical And Mechanical Properties ◽  
Computer Programs ◽  
Complex Task ◽  
Real Property ◽  
Initial Tension ◽  
Technological Processes

Multilayer fabrics made of polyethylene threads are widely used for products of real property and tactical equipment of servicemen capable of protecting the human body from the influence of firearm, cold, cutting, spiny weapons, shock and shock-fractional influences. Optimization of the process of their manufacture is to optimize the tension of the main polyethylene threads in front of the formation zone. To do this, it is necessary to determine the change in relative tension on zones of filling of polyethylene threads on a loop. The execution of this complex task should be based on the use of specially designed computer programs. Taking into account the specifics of the processing of threads on a weaving machine, when determining the relative tension in each individual zone, it is necessary to use a recursion algorithm when the initial tension of the thread from the previous zone will be input for the next zone. Designing new and improvement of existing technological processes of processing polyethylene complex threads on weaving machines requires a change in relative tension on zones of refueling of basic threads. The execution of this complex task should be based on the use of specially designed computer programs using a recursion algorithm. Determination of the change in relative tension on zones of filling of polyethylene complex threads on weaving machines, taking into account the material of the guide, will improve the technology of manufacturing multilayer fabrics that are used to manufacture products of real property and tactical equipment of servicemen capable of protecting the human body from the influence of firearms, cold, cutting, spiny weapons, shock and shock-fractional influences. Improvement of existing technological processes of processing polyethylene complex threads on weaving machines will reduce the downtime that arise when breaking the threads. This negatively affects the productivity of weaving machine tools, reduces the quality of multilayer tissues. Minimization of tension in each line of refueling line of basic polyethylene complex threads will reduce the likelihood of a cliff of the thread, which is important for improving technological processes from the position of increasing the productivity of weaving machine tools and the quality of multilayer tissues. Mathematical provision of a computer program requires the development of thread interaction models with surfaces of scala, framing guides, holes of the remission framework taking into account the real physical and mechanical properties of complex threads and yarns and their real geometric and constructive parameters. The main factor affects the growth of the tension of polyethylene complex threads is the force of friction. It characterizes the friction properties of the threads and conditions of their interaction with the surfaces of the scala, framing guides, holes of the striped frames.

scholarly journals Influence Structures of The Machine Tools on Roughness in Turning

2020 ◽  
Vol 14 ◽  
Keyword(s):  
Surface Quality ◽  
Machine Tools ◽  
Numerical Control ◽  
Elastic Behaviour ◽  
Machined Surface ◽  
Good Surface ◽  
Machined Surface Quality ◽  
Finished Surface ◽  
In Series

The final quality of machining is directly a function of the type of machine used. The geometrical and micro quality geometrical of finished surface are one of the principal goals of machining. During the operation of turning, in particular, the elastic behaviour of the pin controls the surface quality machined. To say that the rigidity of the machine must be largest possible is not sufficient. The design of the axes of movement of the machine must take account of the effects static, kinematics, dynamic of the mass. The rigidity and the conditions of maintenance by the stages must be qualified in comparison with the results sought in term of machined surface quality. To characterize the effect of the vibrations of the machine tools on the quality of the machined surfaces a study was undertaken on two different lathes, a conventional turn and a turn with numerical control. The results of roughness show that the machine tool exploits a great role the machined surface quality. The rigidity of the machine and its capacities damping are prevalent factors to have a good surface quality.To this end the choice of a thing rigid and damping tool is essential for any trial run and any industrial machining in series.

scholarly journals Comparison of Surface Roughness When Turning and Milling

2021 ◽  
Author(s):  
Abdulwahab Mgherony ◽  
Balázs Mikó ◽  
Gabriella Farkas
Keyword(s):  
Surface Roughness ◽  
Geometric Model ◽  
Cutting Parameters ◽  
Machining Process ◽  
Depth Of Cut ◽  
Real Surface ◽  
Machined Surface ◽  
Longitudinal Turning ◽  
Machining Process Planning

The quality of a machined surface can be described by macro and micro parameters, like the size error, the form and position error or the surface roughness. The task of machining process planning is to find the best machining method and parameters, which ensure the required quality. In this article, the surface roughness in the case of turning and milling technologies is analysed. The effect of the cutting parameters (feed at turning and depth of cut at milling) and the tool parameter (corner radius) are investigated. The results are compared with the theoretical geometric model of surface roughness. In longitudinal turning as well as in constant Z-level milling, the geometric model of surface roughness is similar. The article presents whether the real surface roughness is similar too.

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