The paper presents the results of researches regarding determination of the functional parame- te... more The paper presents the results of researches regarding determination of the functional parame- ters that characterize the energetic expression of the linear actuators. The optimization of the working conditions on the basis of the energetic characteristics of linear electromechanic actuator leads to the ra- tional use of the operating system of the trained equipment and the electric power.
Throughout my doctoral study I have encountered the problem of milling vulcanized rubber in a com... more Throughout my doctoral study I have encountered the problem of milling vulcanized rubber in a company specialized in the production of V-belts, which uses milling to generate the final surface of an assortment of V-belts. In this process I have encountered difficulties starting from fastening up to milling the rubber. At vulcanized rubber any error makes the workpiece to be rejected without the possibility to fix it, or not even to reuse the material. The reject rate at milling this assortment of V-belts is almost 40%. After we studied the literature from domain, we observed that the cutting issue of flexible polymeric materials is not well defined from some points of view, for this reason we made an experiment to observe the behavior of rubber at cryogenic and conventional milling, with a cutting speed of 2355m/min at a feed range between 0.0025 mm /tooth and 0.02 mm/tooth. As a result of the experimental study of milling vulcanized rubber type 3540, we observed that for the workpieces that were cooled with liquid nitrogen, the reject rate was reduced down to 20%. We also observed that, for the workpieces which were cooled with liquid nitrogen, feed milling had a small influence on the obtained surface quality.
This paper fits into an experimental researches complex, regarding the surface roughness dependen... more This paper fits into an experimental researches complex, regarding the surface roughness dependency on the cutting parameters of 7136 aluminum alloy machining. The purpose of this paper is to identify by experiments the influence of feed per tooth variation on surface roughness. A range of feed per tooth was used while the cutting speed and the cutting depth were constrained per minimum and maximum requirements defined for the given cutting tool. The experiments were conducted on Al7136 because it is a new material and I have identified the need for its use in the aircraft industry.
Surface quality is affected by various processing parameters and inherent uncertainties of the me... more Surface quality is affected by various processing parameters and inherent uncertainties of the metal cutting process. Therefore, the surface roughness anticipation becomes a real challenge for engineers and researchers. In previous researches [1] I have investigated the feed rate influence on surface roughness and manufacturing time reduction. The 7136 aluminum alloy was machined by end milling operation using standard tools for aluminum machining. The purpose of this paper is to identify by experiments the influence of cutting speed variation on surface roughness. The scientific contribution brought by this research is the improvement of the end milling process of 7136 aluminum alloy. This material is an aluminum alloy developed by Universal Alloy Corporation and is used in the aircraft industry to manufacture parts from extruded profiles. The research method used to solve the problem is experiment. A range of cutting speeds was used while the cutting depth and the feed per tooth were constrained per minimum and maximum requirements defined for the given cutting tool. The experiment was performed by using a 16 mm End milling cutter, holding two indexable cutting inserts. The machine used for the milling tests was a HAAS VF2 CNC. The surface roughness (response) was measured by using a portable surface roughness tester (TESA RUGOSURF 20 Portable Surface Finish Instrument). Following the experimental research, results were obtained which highlight the cutting speed influence on surface roughness. Based on these results we created roughness variation diagrams according to the cutting speed for each value of feed per tooth and cutting depth. The final results will be used as data for future research.
IOP Conference Series: Materials Science and Engineering, 2019
In order to find solutions for different medical applications like implants and reconstructions i... more In order to find solutions for different medical applications like implants and reconstructions in clinical dentistry, orthopaedic or spinal implants, the polyetheretherketones have achieved a remarkable application because of their properties. The polyetherketone materials combine excellent wear resistance with very good mechanical properties, even under thermal load. Because of these qualities it is used also in different applications in automotive, aerospace and food industry. For each application, no matter if the process to obtain different shape is extrusion, injection moulding or machining by turning or milling, the surface roughness value is critical. For pieces with complex surfaces some finishing operations are necessary. The ball nose end milling process is recommended in this case because of its versatility. In ball nose end milling process the influence of tool axis inclination angle has a big influence upon surface roughness value. In this way theoretical studies are r...
In the current paper, some aspects regarding the quality of the surface machined under different ... more In the current paper, some aspects regarding the quality of the surface machined under different lubrication conditions is being assessed: cutting under a jet of cutting fluid, minimum quantity lubrication cutting, dry cutting. The objective was to assess the results obtained after MQL cutting in comparison with dry cutting and cutting under a jet of cutting fluid. The variables of the cutting regime were the feed rate and the type of milling (climb and conventional). This study has an important ecological impact over the use of cutting fluids.
¶ Abstract: Paper present some concepts about the logistics applications in industrial activities... more ¶ Abstract: Paper present some concepts about the logistics applications in industrial activities. It's presented the relationship between the industrial system and economic environment and a possible approach of management of logistic activities. Key words: ...
A modern method of cutting materials is the abrasive water jet cutting method. It is a method tha... more A modern method of cutting materials is the abrasive water jet cutting method. It is a method that is in full ascension regarding the level of usability in production. In order to have the adequate setup for water jet cutting on a certain system, the surface quality, the kerf aspect, the shape and respectively the form of the obtained part have to be analysed. This paper presents the results obtained after cutting one square shaped part, made of 1C45 material. In the study, there were analysed both the inside and the outside of the cut, the kerf width, the aspect of the taper and the profile deviation.
The manufacturing process of the molding, is widely used in the polymeric material processing ind... more The manufacturing process of the molding, is widely used in the polymeric material processing industry which is an expensive and difficult process. Depending on the configuration of the parts most of the times they can be obtained more productively and inexpensively by combining molding process with the cutting process. In this situation intervenes the cutting manufacturing process, which is rarely used, because it is difficult to implement. This aspects has imposed the manufacturers of components from polymeric materials to search and find new solutions to improve the machining of these materials. The purpose of this paper is to determine some factors of the surface quality of vulcanized rubber obtained by milling, depending on the cutting conditions as to achieve an increase of productivity and application domain and to decrease manufacturing costs.
Within the unique and small series industrial product development, especially custom-made product... more Within the unique and small series industrial product development, especially custom-made products assuming major responsibilities on management is required: assuming the responsibility of innovative technological solutions that ensure quality, the specification of purchase components with a reasonable quality/price rate, and with a quick response to market requirements with a very short production cycle. The generic product development model, based on the use of ontologies, will allow addressing the structuring of a variety of products, even of families of products, so that future projects may benefit from the historical background of a certain configuration. The purpose of this paper is to develop a generic ontology model for machine, machinery and equipment type products, which should be a support tool assisting the decision making on the structure and composition of the product. For the development of an ontology of an industrial product type it is required a framework common to...
The paper presents the results of researches regarding determination of the functional parame- te... more The paper presents the results of researches regarding determination of the functional parame- ters that characterize the energetic expression of the linear actuators. The optimization of the working conditions on the basis of the energetic characteristics of linear electromechanic actuator leads to the ra- tional use of the operating system of the trained equipment and the electric power.
Throughout my doctoral study I have encountered the problem of milling vulcanized rubber in a com... more Throughout my doctoral study I have encountered the problem of milling vulcanized rubber in a company specialized in the production of V-belts, which uses milling to generate the final surface of an assortment of V-belts. In this process I have encountered difficulties starting from fastening up to milling the rubber. At vulcanized rubber any error makes the workpiece to be rejected without the possibility to fix it, or not even to reuse the material. The reject rate at milling this assortment of V-belts is almost 40%. After we studied the literature from domain, we observed that the cutting issue of flexible polymeric materials is not well defined from some points of view, for this reason we made an experiment to observe the behavior of rubber at cryogenic and conventional milling, with a cutting speed of 2355m/min at a feed range between 0.0025 mm /tooth and 0.02 mm/tooth. As a result of the experimental study of milling vulcanized rubber type 3540, we observed that for the workpieces that were cooled with liquid nitrogen, the reject rate was reduced down to 20%. We also observed that, for the workpieces which were cooled with liquid nitrogen, feed milling had a small influence on the obtained surface quality.
This paper fits into an experimental researches complex, regarding the surface roughness dependen... more This paper fits into an experimental researches complex, regarding the surface roughness dependency on the cutting parameters of 7136 aluminum alloy machining. The purpose of this paper is to identify by experiments the influence of feed per tooth variation on surface roughness. A range of feed per tooth was used while the cutting speed and the cutting depth were constrained per minimum and maximum requirements defined for the given cutting tool. The experiments were conducted on Al7136 because it is a new material and I have identified the need for its use in the aircraft industry.
Surface quality is affected by various processing parameters and inherent uncertainties of the me... more Surface quality is affected by various processing parameters and inherent uncertainties of the metal cutting process. Therefore, the surface roughness anticipation becomes a real challenge for engineers and researchers. In previous researches [1] I have investigated the feed rate influence on surface roughness and manufacturing time reduction. The 7136 aluminum alloy was machined by end milling operation using standard tools for aluminum machining. The purpose of this paper is to identify by experiments the influence of cutting speed variation on surface roughness. The scientific contribution brought by this research is the improvement of the end milling process of 7136 aluminum alloy. This material is an aluminum alloy developed by Universal Alloy Corporation and is used in the aircraft industry to manufacture parts from extruded profiles. The research method used to solve the problem is experiment. A range of cutting speeds was used while the cutting depth and the feed per tooth were constrained per minimum and maximum requirements defined for the given cutting tool. The experiment was performed by using a 16 mm End milling cutter, holding two indexable cutting inserts. The machine used for the milling tests was a HAAS VF2 CNC. The surface roughness (response) was measured by using a portable surface roughness tester (TESA RUGOSURF 20 Portable Surface Finish Instrument). Following the experimental research, results were obtained which highlight the cutting speed influence on surface roughness. Based on these results we created roughness variation diagrams according to the cutting speed for each value of feed per tooth and cutting depth. The final results will be used as data for future research.
IOP Conference Series: Materials Science and Engineering, 2019
In order to find solutions for different medical applications like implants and reconstructions i... more In order to find solutions for different medical applications like implants and reconstructions in clinical dentistry, orthopaedic or spinal implants, the polyetheretherketones have achieved a remarkable application because of their properties. The polyetherketone materials combine excellent wear resistance with very good mechanical properties, even under thermal load. Because of these qualities it is used also in different applications in automotive, aerospace and food industry. For each application, no matter if the process to obtain different shape is extrusion, injection moulding or machining by turning or milling, the surface roughness value is critical. For pieces with complex surfaces some finishing operations are necessary. The ball nose end milling process is recommended in this case because of its versatility. In ball nose end milling process the influence of tool axis inclination angle has a big influence upon surface roughness value. In this way theoretical studies are r...
In the current paper, some aspects regarding the quality of the surface machined under different ... more In the current paper, some aspects regarding the quality of the surface machined under different lubrication conditions is being assessed: cutting under a jet of cutting fluid, minimum quantity lubrication cutting, dry cutting. The objective was to assess the results obtained after MQL cutting in comparison with dry cutting and cutting under a jet of cutting fluid. The variables of the cutting regime were the feed rate and the type of milling (climb and conventional). This study has an important ecological impact over the use of cutting fluids.
¶ Abstract: Paper present some concepts about the logistics applications in industrial activities... more ¶ Abstract: Paper present some concepts about the logistics applications in industrial activities. It's presented the relationship between the industrial system and economic environment and a possible approach of management of logistic activities. Key words: ...
A modern method of cutting materials is the abrasive water jet cutting method. It is a method tha... more A modern method of cutting materials is the abrasive water jet cutting method. It is a method that is in full ascension regarding the level of usability in production. In order to have the adequate setup for water jet cutting on a certain system, the surface quality, the kerf aspect, the shape and respectively the form of the obtained part have to be analysed. This paper presents the results obtained after cutting one square shaped part, made of 1C45 material. In the study, there were analysed both the inside and the outside of the cut, the kerf width, the aspect of the taper and the profile deviation.
The manufacturing process of the molding, is widely used in the polymeric material processing ind... more The manufacturing process of the molding, is widely used in the polymeric material processing industry which is an expensive and difficult process. Depending on the configuration of the parts most of the times they can be obtained more productively and inexpensively by combining molding process with the cutting process. In this situation intervenes the cutting manufacturing process, which is rarely used, because it is difficult to implement. This aspects has imposed the manufacturers of components from polymeric materials to search and find new solutions to improve the machining of these materials. The purpose of this paper is to determine some factors of the surface quality of vulcanized rubber obtained by milling, depending on the cutting conditions as to achieve an increase of productivity and application domain and to decrease manufacturing costs.
Within the unique and small series industrial product development, especially custom-made product... more Within the unique and small series industrial product development, especially custom-made products assuming major responsibilities on management is required: assuming the responsibility of innovative technological solutions that ensure quality, the specification of purchase components with a reasonable quality/price rate, and with a quick response to market requirements with a very short production cycle. The generic product development model, based on the use of ontologies, will allow addressing the structuring of a variety of products, even of families of products, so that future projects may benefit from the historical background of a certain configuration. The purpose of this paper is to develop a generic ontology model for machine, machinery and equipment type products, which should be a support tool assisting the decision making on the structure and composition of the product. For the development of an ontology of an industrial product type it is required a framework common to...
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