Showing papers by "Grzegorz Królczyk published in 2014"

Microhardness and Surface Integrity in Turning Process of Duplex Stainless Steel (DSS) for Different Cutting Conditions

Abstract: The objective of the investigation was to identify microhardness of surface integrity (SI) after turning with wedges of coated sintered carbide. SI is important in determining corrosion resistance, and also in fatigue crack initiation. The investigation included microhardness analyses in dry and wet machining of duplex stainless steel. The microhardness of SI for various cutting speeds was compared. It has been shown that wet cutting leads to the decrease of SI hardening depth, while increasing the rounded cutting edge radius of the wedge increases the maximum microhardness values and the hardening depth. An infinite focus measurement machine has been used for the rounded cutting edge radius analysis. The study has been performed within a production facility during the production of electric motor parts and deep-well pumps as well as explosively cladded sheets.

Experimental analysis of surface roughness and surface texture of machined and fused deposition modelled parts

Abstract: The objective of the investigation was to identify surface integrity of machined parts by turning and by Fused Deposition Modelling (FDM) additive method produced ones. Surface analysis was made by using novel metrology methods: auto correlation and gradient distribution. An Infinite Focus Measurement Machine (IFM) was used for the surface texture analysis. The study was performed within a production facility during the prototyping process of new products.

Experimental analysis by measurement of surface roughness variations in turning process of duplex stainless steel

Abstract: The objective of the investigation was to identify surface roughness after turning with wedges of coated sintered carbide. The investigation included predic ting the average surface roughness in the dry machining of Duplex Stainless Steel (DSS) and the determination of load curves together with roughness profiles for various cutting conditions. The load curves and roughness profiles for various cutting wedges and variable cutting parameters were compared. It has been shown that dry cutting leads to a decrease in friction for lubricated surfaces, providing a small initial contact area where the surface is contacted. The st udy has been performed within a production facility during the production of electric motor parts and deep-well pumps. Keywords: turning, coatings, friction-reducing, optical microscopy, surface roughness analysis and models. © 2014 Polish Academy of Sciences. All rights reserved 1. Introduction Engineering surfaces, particularly those generated using multi-step manufacturing processes and intended for tribological applications such as bearings and gears, rarely if ever have perfectly normal distributed elevations [1]. Surface roughness measurements of any workpiece are among the most important ones in length and angle metrology, both in theory and practice. According to Wieczorowski et al. [2], there are great discrepancies in these measurements because of the large variety of instruments for surface roughness analysis. Hence, three-dimensional surface topography parameters are necessary for assessing the surface roughness characteristics more effectively [3]. According to Mahovic Poljacek et al. [4], a precise characterization of roughness and surface topography is of prime importance in many engineering industries because certain functional properties of the materials are often determined by the surface structure and characteristics. Estimation of the magnitude of surface roughness under the given cutting conditions resulting from metal removal operations is one of the major goals in this area [5, 6]. According to Benardos and Vosniakos [7], surface roughness is a widely used index of product quality and in most cases a technical requirement for mechanical products. Achieving the desired surface quality is of great importance for the functional behaviour of a part. Surface profilometry is for many years a well-known method of topography inspection [8–12]. Topography parameters represent surface properties is much better than 2D ones. Using the surface parameters can be determined functions describing surface behaviour. The workpiece material is duplex stainless steel because this stainless steel is widely used for many industrial applications due to its unique properties. Cabrera et al. [13] and Park et al. [14] consider that the good combination of their mechanical properties (high strength and toughness) and corrosion resistance makes them of great interest for a wide range of

Effect of the disc processing technology on the vibration level of the chipper during operations

Abstract: The purpose of this article is to present the technological repair process of the mobile disc chipper used for crushing raw wood into chips of a certain size Mobile disc chippers are used in the pulp - paper industry and fibreboard manufacturing plants The paper presents the technology of repairing the disc chipper and the balancing process of the disc chipper in its own bearings The article also presents the influence of unbalanced machine elements on the human body Svrha ovog rada je prikazivanje tehnologije reparacije stroja za usitnjavanje drva koji se koristi za usitnjavanje drva u cestice određene velicine Mobilni stroj za usitnjavanje drva koristi se u proizvodnji papira i postrojenjima za proizvodnju vlakana Rad prikazuje tehnologiju popravka i balansiranje stroja U clanku se također predstavlja utjecaj djelovanja neuravnoteženih strojnih elemenata na ljudsko tijelo

Monitoring of focusing tube wear during abrasive waterjet (AWJ) cutting of AISI 309

Abstract: The paper deals with the investigating the possibility of using vibrations as a potential source of information for the detection of the malfunctions during the abrasive supplaying and focusing tube wear in the process of AWJ. The tested material was the stainless steel AISI 309. Variable factors in the experiment were the abrasive mass flow ma and the focusing tube diameter df. The scanned vibration signal of the material was subjected to frequency analysis. With the increase of the abrasive mass flow, the shift of the amplitudes will follow the opposite direction and decrease. Frequency spectra of all assessed signals are similar by shape in the high- frequency area.

Study of the surface integrity microhardness of austenitic stainless steel after turning

Abstract: G. Krolczyk i dr. Analiz a mikrotvrdoce integriteta povrsine austenitnog nehr đajuceg celika nakon tokarenja Tehnicki vjesnik 21, 6(2014), 1307-1311 1307 ISSN 1330-3651 (Print), ISSN 1848-6339 (Online) UDC/UDK [620.178:669.14.018.62]:621.941

Investigations Into Surface Integrity in the Turning Process of Duplex Stainless Steel

Abstract: Summary The objective of the investigation was to identify surface roughness and surface topography parameters after the turning of Duplex Stainless Steel (DSS) with wedges of coated sintered carbide. The auto correlation and gradient distributions for variable cutting parameters were compared. An Infinite Focus Measurement Machine (IFM) was used for the surface texture analysis. The study was performed within a production facility during the machining of electric motor parts and deep-well pumps.

Quality Evaluation of Surface Layer in Highly Accurate Manufacturing

Abstract: Stanislaw Legutko, Faculty of Mechanical Engineering and Management, Poznan University of Technology, 3 Piotrowo Street, 60-965 Poznan, Poland. stanislaw.legutko@put.poznan.pl Grzegorz Krolczyk, Faculty of Production Engineering and Logistics, Opole University of Technology, 76 Proszkowska Street, 45-758 Opole, Poland. g.krolczyk@po.opole.pl Jolanta Krolczyk, Department of Biosystems Engineering, Opole University of Technology, 76 Proszkowska Street, 45758 Opole, Poland. j.krolczyk@po.opole.pl

Materials Flow Analysis in the Production Process - Case Study

Abstract: The paper presents an analysis of the materials flow in the company on the example of the production process of the selected product. The analysis was carried out in three stages. This division has enabled to take into account many factors that have a significant impact on the internal transport during production. The first step in the analysis was to determine the current situation of the flow of materials. In the second stage, the obtained data were used to develop a detailed program of internal transport, associated with the production of the considered product, and the last stage of the analysis was to identify opportunities for rationalization actions. The rationalization concerned the machine tools spatial location, the choice of handling equipment and transport tasks.

Microhardness changes gradient of the duplex stainless steel (DSS) surface layer after dry turning

Abstract: The article presents the gradient of microhardness changes as a function of the distance from the material surface after turning with a wedge provided with a coating with a ceramic intermediate layer. The investigation comprised the influence of cutting speed on surface integrity microhardness in dry machining. The tested material was duplex stainless steel (DSS) with two-phase, ferritic-austenitic structure. The tests have been performed under production conditions during machining of parts for electric motors and deep-well pumps.

Influence of Minimum Quantity Cooling Lubrication (MQCL) on Chip Formation Zone Factors and Shearing Force in Turning AISI 1045 Steel

Abstract: The paper presents the results of research on the effect produced by various cooling methods on the chip thickness ratio, shear angle and shearing force. Dry cutting, cooling by compressed air and the MinimumQuantityCoolingLubrication (MQCL) method when finish turning of carbon steel with different speeds of cutting and feed rates were compared. The investigations were performed in accordance with the Parameter Space Investigation method. The advantage of the MQCL is confirmed by lower values of the chip thickening ratio, shearing force and higher values of the shear angle. Depending on the cutting conditions, the efficiency of the MQCL method is 6 to 30% higher compared to dry machining.

Dynamic Balancing of the Threshing Drum in Combine Harvesters – The Process, Sources of Imbalance and Negative Impact of Mechanical Vibrations

Abstract: The purpose of this article is to present the description of the process of the dynamic balancing of threshing drum in combine harvesters as well as the sources of imbalance. The dynamic balancing analysis was carried out in production facility on dynamic balancing machine. Dynamic balancing of slats of the combine harvester threshing drum was determined by reference to the specified mass dynamic unbalance. The article also presents the influence of unbalanced machine elements on the human body.

Influence of Technological Cutting Parameters on Surface Texture of Austenitic Stainless Steel

Abstract: The paper presents the contribution in engineering of surfaces particularly in surface texture of Austenitic Stainless Steels. The objective of the investigation was to determine the surface texture of austenitic stainless steel after turning with coated carbide tool point. The investigation included geometrical parameters of Surface Integrity for different technological cutting parameters in dry turning process of austenitic stainless steel. The article presents the surface roughness parameters with the roughness profiles (irregular slopes). The percentage of isotropic surfaces and Bearing Area of ​​Primary Model. Analyses were performed for variable cutting parameters. An Infinite Focus Measurement Machine (IFM) was used for the surface texture analysis. The study was performed within a production facility during the machining of electric motor parts and deep-well pumps.

Effect of Minimum Quantity Cooling Lubrication (MQCL) on Chip Morphology and Surface Roughness in Turning Low Carbon Steels

Abstract: The paper presents the results of research on the effect produced by modern cooling methods on the chip shapes and surface roughness when finish turning of ASTM A53 and AISI 1010 low carbon steels. Dry cutting, cooling by compressed air and the Minimum–Quantity–Cooling–Lubrication (MQCL) method were compared. The MQCL method is more effective for machining low carbon steel and ensures a usable chip shape and lesser surface roughness. Depending on the cutting conditions, the efficiency of the MQCL method is 10 to 30 % higher compared to dry machining. Examples of experimental investigations about reducing the use of cooling lubricant substances in turning process can be found in the open literature [1, 2].

Investigations Regarding the Influence of Surface Topography on Emissive Properties of Material

Abstract: In the paper analysis of surface topography influence on emissivity of metals was shown. This was performed for infrared band comprising wavelength region of 7.5 13 micrometers. Appropriate characterization and description of object emissivity has a crucial influence on accuracy of IR system for remote temperature measurement, e.g. IR thermography or pyrometry. These properties depend on many factors, including surface topography of material, where especially cavities play a very important role. In references so far emissivity are discussed mainly as influence of type of material (metal, dielectric), its temperature, wavelength or direction of emission. In the paper characterizing emissivity of construction materials in connection with 3D surface topography.

Thermaltransport phenomenon of submerged arc welding process

Abstract: In present work, thermal transport considering heat radiation by oval heat source and heat transfer of molten moving electrode was presented. In present paper, an analytical solution was presented by aggregating temperature increments caused by applying liquid metal and heat radiation of moving electrode. The assumptions for the study were heat source of temperature of applied metal in oval shape and Gaussian distribution of electric heat source. Accuracy of the solution was verified comparing experimental results.

Surface Morphology of Duplex Stainless Steel (DSS) in Dry Turning Process

Abstract: Sustainable manufacturing in most developed countries is one of principal goals in today manufacturing industry. The reduction in use of oil-based CLFs is most ecologically important task of machining processes. The paper presents the contribution in engineering of surfaces particularly in surface morphology of Stainless Steels. The objective of the investigation was to determine the surface texture of duplex stainless steel after turning with coated carbide tool point. The investigation included geometrical parameters of Surface Integrity for different cutting parameters in dry turning process of duplex stainless steel.

Influence of Cutting Parameters on Surface Morphology of Austenitic Stainless Steel after Turning

Abstract: The study presents the contribution in engineering of surfaces particularly in surface morphology of Austenitic Stainless Steels. The objective of the investigation was to determine the surface morphology of austenitic stainless steel after turning with coated carbide tool point. The investigation included geometrical parameters of SI for different cutting parameters in dry turning process of austenitic stainless steel. The study has been performed within a production facility during the production of electric motor parts and deep-well pumps.