The article presents the experimental results of investigation of the pumps shaft surface made of stainless steel after burnishing process. The process of burnishing shafts proposed here aims at increasing the service durability of marine pump shafts of seawater installations, which should give economic benefits in comparison with traditional methods. Burnishing process enables the achievement of high smoothness of machined surface together with the surface layer hardening. This process has been performed in industrial experience on universal machine tools and on CNC machines but it is regarded as plastic tooling. Therefore, the final formation of dimensions and service properties with the use of burnishing constitutes a chipless and dustless treatment, which allows for ranking burnishing among ecological tooling methods. The properties of the surface layers determine the tribological properties of the shaft. The methods of scanning electron microscopy (SEM), atomic force microscopy (AFM) and nanoindentation (NI) were used. The morphology of the changed layers formed by plastic deforming of steel during burnishing treatment was investigated on micro- and nanolevel by SEM and AFM after 1, 2, 3 and 4 passed of burnishing tool. The values of microhardness and Young´s modulus were measured on the shaft cross section from the surface till the 50 – 300 μm depth. The presence of the soft changed layer on the hardened shaft surface after burnishing process determines the decrease of the coefficient of friction during exploitation.
New technology with sliding burnishing of holes with cylindrical surface, made of hardened steel (60 HRC), is presented in the paper. Burnishing process was applied with specially designed tools. These tools can be used in CNC lathes and machining centres. After burnishing operation on hole ø 30 mm in satellite gear wheel the surface roughness parameter Ra = 0,02-0,04 mm was obtained. The method and results of research as well as technological conclusions are presented.
PL
W artykule przedstawiono nową technologię otworów o gładkiej powierzchni, wykonanych w elementach maszyn ze stali hartowanej o twardości 60 HRC z zastosowaniem nagniatania ślizgowego. Obróbka wykończeniowa otworów odbywa się z użyciem specjalnych narzędzi nagniatających stosowanych na tokarkach CNC i centrach obróbkowych. Po nagniataniu otworu ø 30 mm w kole zębatym przekładni satelitarnej uzyskano powierzchnię o parametrze Ra = 0,02-0,04 mm. Podano przebieg i wyniki badań doświadczalnych oraz wnioski i zalecenia technologiczne.
The paper presents the environmental, economic and exploitation aspects of the use of burnishing rolling treatments. The validity of the application of the plastic surface treatment in modern technological processes by replacing expensive, energy-intensive defects processing (grinding, turning) was shown. One confirmed the possibility of obtaining resource saving products using burnishing with not worsen their utility quality as well as a lower unit price compared to products prepared using conventional technology.
Currently, the manufacturing management board applies technologies in line with the concept of Industry 4.0. Cyber-physical production systems (CPSs) mean integrating computational processes with the corresponding physical ones, i.e., allowing work at the operational level and at the strategic level to run side by side. This paper proposes a framework to collect data and information from a production process, namely, the burnishing one, in order to monitor real-time deviations from the correct course of the process and thus reduce the number of defective products within the manufacturing process. The proposed new solutions consist of (i) the data and information of the production process, acquired from sensors, (ii) a predictive model, based on the Hellwig method for errors in the production process, relying on indications of a machine status, and (iii) an information layer system, integrating the process data acquired in real time with the model for predicting errors within the production process in an enterprise resource planning (ERP) system, that is, the business intelligence module. The possibilities of using the results of research in managerial practice are demonstrated through the application of an actual burnishing process. This new framework can be treated as a solution which will help managers to monitor the production flow and respond, in real time, to interruptions.
Throughout planning of technological process of manufacturing or regenerating machine components, the method of burnishing, the machining conditions, the shape and number of burners should be selected. The choice of static pressure conditions during burnishing process is dependent on how the pressure components are applied to the workpiece surface, which can be elastic or rigid. The reliability of working machine and equipment is very important in the engineering, power, metallurgical or marine industries. For example, on a ship during a cruise, are made repairs of individual components of the ship’s machinery. Often are regenerated external cylindrical surfaces (e.g. shaft seals of seawater pumps), for this purpose can be proposed burnishing process can be proposed as a finishing, which enables to obtain the technological quality requirements of the products surface layer. The effect of technological conditions of burnishing process on the degree of relative strain hardening and surface roughness reduction ratio were presented. The burnishing process carried out for duplex cast steels series GX2CrNiMoCuN25–6–3–3. The use of duplex cast steel burnishing process is a novelty technology. The experimental investigation were obtained in the surface layer increase in hardness and the material ratio curve a convex shaped, which, taking into account the load capacity of the surface will be directly affected by its resistance to wear and corrosion. The experimental research by application of the burnishing process were made in the Laboratory of Production Engineering of the Department of Marine Maintenance. After the studies it was found that the hardness of the surface layer and the roughness of the shaft necks an important influenced by technological parameters of processing (the recommended parameters: burnishing speed vn = 70 m/min; feed rate fn = 0.2 mm/rev; depth of burnishing an = 1.0 mm; number of machining passes i = 2). The aim of applying burnishing may be, for example, the need to increase surface smoothness and dimensional accuracy of part.
PL
Celem pracy było wyznaczenie wpływu parametrów obróbki plastycznej przez nagniatanie na zmianę współczynnika zmniejszenia chropowatości powierzchni i względnego stopnia umocnienia warstwy wierzchniej staliwa typu dupleks. W artykule przedstawiono wyniki badań doświadczalnych nagniatania staliwa typu dupleks w gatunku GX2CrNiMoCuN25–6–3–3. Nagniatanie czopów wałów przeprowadzono z wykorzystaniem nagniataka krążkowego (NK-01). Po przeprowadzonych badaniach eksperymentalnych określono, że występuje wzrost stopnia umocnienia, następuje zmniejszenie chropowatości, a krzywa udziału materiałowego ma kształt wypukły, co, biorąc pod uwagę nośność powierzchni, wpływa bezpośrednio na jej odporność na zużywanie ścierne i korozyjne. Stwierdzono, że na twardość warstwy wierzchniej oraz chropowatość zewnętrznych powierzchni walcowych mają wpływ parametry technologiczne: posuw nagniatania, dosuw nagniataka, prędkość nagniatania i liczba przejść obróbkowych.
In the manufacturing of machine elements was important to technological quality products. In surface engineering one of the economic and ecological treatments used for technological properties were burnishing rolling – pressuring process. This is a surface plastic forming a local plastic deformation based on the overall impression given by smooth and hard tool. In production, engineering cylindrical outer surfaces (e.g. plugs propulsion shaft centrifugal pumps seawater) were finishing. You can therefore propose burnishing in exchange for abrasive machining. The article presents the influence of parameters for burnishing rolling – pressuring process on the degree of relative strain hardening and surface roughness reduction ratio. Burnishing process carried out for 316L stainless steels. After the experimental study, it was determined that there was an increase in hardness and a decrease in roughness of the top outer cylindrical layer of stainless steel, which can be applied to the centrifugal pump shafts ship. Important question to determine in the article of the research was to receive appropriate technological quality. The burnishing due the technological and economic aspect in the production of machine parts in exchange for the abrasive processing can be used. After the experiments, it was found that the technical parameters are influenced by the hardness and the roughness of the outer cylindrical surfaces and the material ratio curve a convex shaped, which, taking into account the load capacity of the surface will be directly affected by its resistance to wear and corrosion of the surface layer.
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Purpose: The aim of the study was description to the influence of technological parameters of burnishing process on the degree of relative strain hardening and surface roughness reduction ratio. Design/methodology/approach: Burnishing process carried out for stainless steels X2CrNiMo17-12-2. After the experimental research, it was determined that there was an increase in hardness and a decrease in roughness. The hardness was measured with the use of Vickers hardness tester. Observation of the microstructure of stainless steel samples was carried out using scanning electron microscopy and optical microscopy. The parameters of surface roughness measurements were performed to the principles contained in ISO standards. Findings: In the production and regeneration of metal products used in machine elements is important to technological quality surface layer. In surface engineering one of the ecological and economic treatments used for endurance and technological properties is burnishing. This is a surface forming a local plastic deformation based on the overall impression given by smooth and hard tool. Practical implications: The burnishing due the technological and economic aspect in the production and regeneration of machine parts in exchange for the abrasive processing can be used. In production engineering or technology of repair cylindrical outer surfaces (e.g. plugs propulsion shaft centrifugal pumps seawater) are finishing. You can therefore propose burnishing in exchange for abrasive machining. Originality/value: Important question to determine in the article of the research was to received appropriate technological quality. After the tests, it was found that the technological parameters are influenced by the hardness and the roughness of the outer cylindrical surfaces and the material ratio curve a convex shaped, which, taking into account the load capacity of the surface will be directly affected by its resistance to wear and corrosion of the surface layer.
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