Wyniki wyszukiwania - BazTech

1

Using thermovision for temperature measurements during turning process

Molenda J., Charchalis A.

Journal of KONES

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2018

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Vol. 25, No. 4

293--298

EN

In metal cutting industries, machining processing, especially turning operation is very basic type of machining. For certain processes in manufacturing, it is favourable and necessary to have certain knowledge about heat generation and temperature rise (including average and maximum temperature) during machining process. Increment in maximum temperature at clearance face or at rake face of cutting tool causes the reduction in life of tool. Similarly, the quality of machined surface, a metallurgical structural alteration in tool and workpiece material also depends on the maximum temperature, temperature gradient and cooling rate of both tool and workpiece. Certain physical and chemical reactions that are developed during the cutting process are directly connected with tool wear, power consumption, surface roughness on work piece material and cutting temperature. The natural low of thermal energy gives significant relationship between cutting temperature and cutting parameters in order to improvement of cutting tool’s wok efficiency, quality and accuracy. The heat distribution in cutting tool, in formed chip and in workpiece material strongly depends on (mechanical and chemical) properties of cutting tool and workpiece material, cutting speed, depth of cut, feed rate, nose radius, geometry of tool, type of coolant used and other parameters. This work presents some results of research done during turning steel 235JR realized on conventional lathe CDS 6250 BX-1000 with severe parameters. These demonstrate the necessity of further, more detailed research on turning process temperature, realized for different materials.

2

Influence of lapping plate temperature on roughness parameters of specimens

Molenda J., Charchalis A.

Journal of KONES

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2017

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Vol. 24, No. 2

147--152

EN

Lapping is used in the production of components of the highest quality in terms of form finish accuracy and surface integrity. A number of precision manufacturing applications use lapping process as a critical technology to achieve thickness tolerance and surface quality specification. Because of required parts accuracy tool flatness is the key to the successful machining. To avoid its excessive thermal expansion, plate temperature research was taken. This article goal was to check the influence of lapping wheel temperature on workpiece roughness after lapping process. In earlier work, authors investigated the dependence between time and the temperature of executory system elements. Tests showed that after five hours of machine working temperature stabilizes and slightly fluctuated around a certain value. Thus, this work concerns lapping results in this elevated temperature. Research was proceed during Al2O3 elements lapping. It was realised with use of ABRALAP 380 lapping machine. The lapping machine executory system consisted of three working conditioning rings. Executory system elements temperature was measured remotely by infrared camera Thermo Gear G100. Elements machining was started after 10, 140, and 270 minutes of machine working time. Studies showed that machine executory system elements temperature affected only the ΔRa parameter, which is higher for surfaces, which were processed starting from 270th minute of machine working time.

3

Using thermovision for machining processes inspection

Molenda J., Charchalis A.

Journal of KONES

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2016

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Vol. 23, No. 3

345--350

EN

During metal cutting process, an increase of the tool and workpiece temperatures can be observed. The heat generated has a negative influence on the tool life and performance. It causes rapid tool wear, plastic deformation of the cutting edge, built-up-edge formation and others. Therefore, the control of cutting temperature is required to achieve the desired tool performance. Temperature is the most frequently measured physical quantity, second only to time. Accurate temperature monitoring improves product quality and increases productivity. Downtimes are decreased, since the manufacturing processes can proceed without interruption and under optimal conditions. In this work, authors propose noncontact infrared method for determining temperature of machining processes. This was mainly due to thermography ability to catching moving targets in real time, to measure temperatures over some area not only in point. As a result of measurement, it is obtained a data set that is presented in a form of a colourful map: a thermogram. Getting an accurate temperature of an object using this method is difficult because of numerous errors, which researchers could done during experiments. This work presents some results of research done during turning and drilling realized on conventional lathe CDS 6250 BX-1000. These demonstrate the usefulness of proposed method to study the machining processes temperature.

4

Results of lapping process executed in elevated temperature

Molenda J., Charchalis A.

Journal of KONES

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2016

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Vol. 23, No. 4

591--596

EN

Lapping is used in the production of components of the highest quality in terms of form finish accuracy and surface integrity. A number of precision manufacturing applications use lapping process as a critical technology to achieve thickness tolerance and surface quality specification. Because of required parts accuracy tool flatness is the key to the successful machining. To avoid its excessive thermal expansion, plate temperature research was taken. This paper goal was to check the influence of temperature of executory system elements on lapping process results. In earlier work, authors investigated the dependence between time and the temperature of executory system elements. Tests showed that after five hours of machine working temperature stabilizes and slightly fluctuated around a certain value. Thus, this work concerns lapping results in this elevated temperature. Research was proceed during Al2O3 elements lapping. It was realised with use of ABRALAP 380 lapping machine. The lapping machine executory system consisted of three working conditioning rings. Executory system elements temperature was measured remotely by infrared camera Thermo Gear G100. Elements machining was started after 10, 140, and 270 minutes of machine working time. Studies showed that machine executory system elements temperature affected only the Ra parameter, which is higher for surfaces, which were processed starting from 270th minute of machine working time.

5

Determining the emissivity at the tool-chip interface during S235JR steel turning

Molenda J., Charchalis A.

Journal of KONES

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2015

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Vol. 22, No. 2

149--154

EN

Temperature on the chip-tool interface is important parameters in the analysis and control of turning process. Due to the high shear and friction, energies dissipated during a machining operation the temperature in the primary and secondary shear zones are usually very high; hence, affect the shear deformation and tool wear. In a single point cutting, heat is generated at three different zones i.e. primary shear zone, chip tool interface and the tool-workpiece interface. The primary shear zone temperature affects the mechanical properties of the work piece – chip material and temperatures at tool-chip and tool-work piece interfaces influence tool wear at tool face and flank respectively. Total tool wear rate and crater wear on the rake face are strongly influenced by the temperature at chip-tool interface. Therefore, it is desirable to determine the temperatures of the tool and chip interface to analyse or control the process. To measure the temperature at the tool-chip interface many experimental methods have been developed over the past century. Since at the interface there is a moving contact between the tool and chip in this work, authors propose infrared method for temperature measuring. To assure possibly high accurate of noncontact temperature measurement there is a need to keep in mind several factors, including determining appropriate value of emissivity. In this work, authors present results of experimental determining emissivity value of tool-chip interface. As initial value, emissivity of polished steel was taken.

6

Ocena stanu technicznego alternatora na podstawie badań termowizyjnych

Styła S., Pietrzyk W.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 4

296-298

PL

W artykule zaprezentowano innowacyjną metodę badania stanu technicznego alternatora, wykorzystującą promieniowanie podczerwone emitowane przez elementy konstrukcyjne prądnicy. Do badań wykorzystano kamerę termowizyjną ThermaCAM E45 firmy FLIR, a uzyskane wyniki opracowano za pomocą specjalistycznego oprogramowania komputerowego FLIR QuickReport. Przedstawiona procedura diagnostyczna jest szybka i bezinwazyjna, co pozwala na dokonanie dokładnej analizy stanu alternatora bez konieczności wymontowywania go z pojazdu.

EN

This article presents an innovatory method of testing for technical condition of an alternator consisting in the use of infrared radiation emitted by the structural elements of the generator. The tests have been performed by means of ThermaCAM E45 thermovision camera manufactured by FLIR and obtained results have been processed by means of FLIR QuickReport specialized software. This diagnostic procedure is a fast and non-invasive method. Therefore an accurate analysis of the alternator condition is possible without its removal from the vehicle.

7

Emissivity of the one - plate lapping machine tool

Molenda J., Barylski A.

Journal of KONES

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2012

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Vol. 19, No. 1

283-288

EN

A number of precision manufacturing applications use lapping process as a critical technology to achieve thickness tolerance and surface quality specification. Typical examples of the processed components are pump parts, transmission equipments, cutting tools, hydraulic and pneumatics, aerospace parts, inspections equipment, stamping and forging. Lapping leads to a surface with low roughness and high precision. It is carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in material removal. The grains activities in the working gap cause also temperature rise of the executory system elements, including lap plate. Because of required parts accuracy tool flatness is the key to the successful machining. To avoid its excessive thermal expansion, plate temperature research was taken. Temperature is the most often measured physical quantity, second only to time. All advantages of infrared technology have led it to become frequently used technique for temperature measurement. It was also used by authors for lapping process observation. To assure accurate noncontact infrared temperature measurement there is a need to keep in mind several factors, including determining appropriate value of emissivity. Incorrectly, designated emissivity results in bigger measuring error. This work presents a method for determining wheel emissivity and its value obtained by presented way. To find emissivity of the lapping plate infrared camera V-20 II produced by VIGO System S.A. and contact thermometer TES1312 Dual K-Type were used. The experiments were carried out on a plate-lapping machine ABRALAP 380 with a grooved cast-iron lapping plate and three conditioning rings. The determined emissivity was equal 0.95 and was bigger than value from the table, as was expected. During lapping wheel surface is in fact very dark due to charging and covering the waste slurry. Obtained value will be used in future measurements.

8

Investigation of semiconductor diode heating based on temperature measurements using a thermovision camera

Litwa M., Wiczyński G.

Poznan University of Technology Academic Journals. Electrical Engineering

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2011

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No. 65

135--141

EN

In the paper, investigations of semiconductor diodę heating to be observed by a rrmovision camera are presented. The presented results are given as time varying waveforms of temperature recorded for the diode case during its heating .