Advanced Materials Research Vol. 837

Abstract: The evaluation of connections between the functional parameters of hydraulic systems and the quality indicators of water, depending on time is obtained with the help of an original automatic calculation program, elaborated by authors. The original automatic calculation program defines the exploitations regimes for the overall outputs installation to be maximum, the total typical energy consumed to be minimum on the work cycle ensemble and the water quality to be according to international settlements. Follow the variation in hydraulic slope water transport channel, the variation between the weir and hydraulic ram level variation. The water depth studies the variation in drainage canal in biological stage.

Abstract: This paper studies the way how a sample with a 40Cr130 coating behaves to contact fatigue wear from the perspective of plastic deformations. The sample is made of an 18MnCr11 alloy steel. The coating was deposited in electric arc using the Smart Arc 350 installation from Sulzer Metco. The samples was subjected to fatigue wear on the AMSLER installation in limit and mixed lubrication conditions. The samples were subjected to wear for 30 hours, at a loading force of 177 N. The moving sample had a rotational speed of 375 rot/min. Different combinations of contact materials were used for the test samples: coating coating and coating base material. The results were highlighted using the QUANTA 200 3D DUAL BEAM electron microscope.

Abstract: Failure Mode and Effects Analysis is a methodology to evaluate a system, design, process, machine or service for possible ways in which failures (problems, errors, risks and concerns) can occur and it has been used in a wide range of industries. Traditional method uses a Risk Priority Number to evaluate the risk level of a component or process. This is obtained by finding the multiplication of three factors, which are the severity of the failure (S), the probability/occurrence of the failure (O), and the probability of not detecting the failure (D). There are significant efforts which have been made in FMEA literature to overcome the shortcomings of the crisp RPN calculation. Fuzzy logic appears to be a powerful tool for performing a criticality analysis on a system design and prioritizing failure identified in analisys FMEA for corrective actions. In this paper we present a parallel between the typical and the fuzzy computation of RPNs, in order to assess and rank risks associated to failure modes that could appear in the functioning of control equipment.

Abstract: In this paper, it is analyzed, in a comparative way, two methods for profiling disc tools (mills or grinding wheels) for generation of specific threads used in the construction of the prosthetic screw for dental implants. It is proposed an analytical method, based on the fundamental theorem of the surfaces enveloping versus a graphical method, developed in CATIA. They are presented numerical examples for the both methods.

Abstract: The research in the last decade regarding their cutting machinability have highlighted the insufficiency of the data for establishing of the optimum cutting processing conditions and the optimum cutting regime. The purpose of this paper is the optimization of the tool life and the cutting speed at the drilling of the stainless steels in terms of the maximum productivity. A nonlinear programming model to maximize the productivity at the drilling of a stainless steel is developed in this paper. The optimum cutting tool life and the associated cutting tool speed are obtained by solving the proposed mathematical model. The use of this productivity model allows greater accuracy in the prediction of the productivity for the drilling of a certain stainless steel and getting the optimum tool life and the optimum cutting speed for the maximum productivity. The obtained results can be used in production activity, in order to increase the productivity of the stainless steels machining. Finally the paper suggests new research directions for the specialists interested in this field.

Abstract: Surface roughness represents an important characteristic in the appreciation of a part quality. A good surface quality can enhance corrosion resistance and fatigue behavior throughout product life cycle. Magnesium alloys have gained in the recent years a larger use due to an excellent ratio between mechanical strength and weight. Cooling conditions are particularly important when machining magnesium. The chips are flammable and highly reactive with water based fluids. Higher temperature favors also the formation kamiya@cc.tuat.ac.jpof built-up edge and worsens surface quality. The present paper analyses the influence of cooling conditions and cutting parameters on surface roughness of the parts made of magnesium alloy. Using design of experiments technique, a series of experiments were organized and based on that a connection between surface quality and cutting conditions was established.

Abstract: This paper presents an optimization of transportation networks using petri holonic enterprises. The development work is leaving the role and functions of holonic enterprise and then implementing a Petri net, which is designed to optimize transport in such an enterprise. The research purpose is to provide industrial users means to make decisions, to obtain short-term forecasts and to be able to build one that will need mechanisms. For simulation using Visual Object Net ++, because it is relatively easy to use, can be used for complex systems and the literature it is recommended for systems with discrete events. In the development of the paper, the holons are considered to be unitary entities represented by a number of system processes running on stations defined on the basis of a predetermined algorithm.

Abstract: It is known that one of the basic requirements of the market economy is product competitiveness; competitiveness ensures their operating performance and the costs of obtaining them and therefore manufacturing costs. Process smoothing of the cylindrical internal surfaces must ensure a very high diameters precision and a low surface roughness. Cylindrical inner surface smoothing can be achieved through the following processes: indoor spinning roller, honing, lapping, etc. Fine machining processes without material removing, ensures based on the initial surface quality, initial quality metal cutting, work regime that is processed, hardness increasing by (20…60)%, roughness Ra=(1.6…0.4)μm, and fine processing procedures with material removal, ensures a high quality of machined surfaces, resulting in roughness Ra=(0.4…0.02)μm. Deformed layer size reducing at the previous processing, and reducing of micro depths serving as lubricant deposits, contributes to increasing wear resistance of cylinder surface. Cylinder inner surface smoothing by honing machines is performed on honing machines with a specially designed tool called hon. In the honing process, abrasive grain trajectories are forming on the cylinder a network of fine spiral lines. If carried out on a flat surface, these helical lines become straight and intersecting an angle 2α. Processing accuracy depends on the accuracy of the previous bore. In this paper, the focus is on several methods of heat engine cylinder forming the passage of the piston and rings share repair and their effect giving the engine operating parameters specified by eliminating the running operation. With the help of experimental and theoretical data and the methodology of approach to the subject, several aspects have been clarified regarding the depth of the asperities on the honed surface compared to a process-smoothed surface. The influence of all factors on the processing results has not been thoroughly explained. The following research methods shall be discussed in the future: improving the method of adjusting the pressure of the centrifugal rollers with the help of an automatically controlled device and the creation of an auxiliary device to adjust the bars to which the rollers are connected according to the internal diameter of the processed cylinders.

Abstract: In common speech, the term redundant is used to label superfluous repetitions that as a rule should be avoided. Nevertheless, redundancy is a linguistic tool that can play a remarkable role in the communication of complex thoughts in both the vernacular and the erudite talking or writing, which includes the field of engineering design. In the Axiomatic Design (AD) point of view, redundancy may increase the complexity of the design solutions (which is measured through their information content), but does not necessarily entail the breach of the ADs independence axiom. Hence, redundant solutions should not be excluded in a regular basis, since the ones that comply with the independence axiom are considered good design. According to this line of reasoning, the pertinence of redundant solutions should be assessed in the onset of the designing processes, bearing in mind the virtues of the likely higher simplicity of the non-redundant solutions. This paper deals with some basic concepts related to redundant design and it should be seen as a contribution to bring more insight on a subject that is not thoroughly reviewed in the known literature. Different forms of redundancy are considered, specifically the reliability motivated active and passive types, and the functionality-related alternative and augmentative kinds. The means to perceive intrinsic redundancy through the examination of the design equations are also provided, as well as some illustrative examples. The implicit conclusions are that redundant designs are much more usual that one can think at a first glance, and that the study of their peculiarities might deserve further attention.