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The thickness variation during sheet deep drawing process has an impact on the quality of the final product and can lead to local material fractures. To minimize this phenomenon caused by varying degrees of stretching in different areas of the sheet, various methods can be employed. This research paper introduces a novel technique for metal sheet deep drawing, specifically designed for parts with complex geometric shapes that exhibit significant variations in deformation levels across different areas. The objective of this method is to enhance the quality of the deep drawing process by reducing thickness variations in the final part. In this proposed approach, the vertical movement of the punch is accomplished through two vertical rotational movements. This increases the flexibility of the deformation process, ensuring that the active tools elements occupy the most advantageous positions determined by the material flow in the die. As a result, the material's deformability is improved, allowing for a higher degree of deformation. Additionally, this new method offers a relatively simple design and kinematics solutions for the press and eliminates the need for lengthy assembly-disassembly times.

The paper presents a new deep drawing sheet metal method in which, due to the complex geometric shape of the part, there are significant variations in the level of deformation in different areas of the piece. The method aims to im-prove the quality in the deep drawing process by reducing the variation of the wall thickness of the part, caused by the different degree of stretching of the sheet in different areas of it. In the proposed method the vertical movement of the punch is completed by two vertical rotational movements of it which will have the effect the increasing the flexibility of the deformation process, the active elements occupying the most favorable position dictated by the material flow in the die. It results an improved material deformability and a higher degree of deformation. Also, the new method offers a relatively simple constructive solution of the press and does not require long auxiliary times for assembly-disassembly.

Significant amounts of dust from the processing of cast iron in the furnace can be considered as by-products for the technological flow from the agglomeration, having an adequate chemical and structural composition. Blast furnace dust contains significant amounts of metals and non-metals that can be recovered by various processing methods. The transformation of these recyclable materials for reuse into metal producing units is essential not only for the conservation of mineral resources but also for the protection of the environment. This paper presents the chemical and mineralogical characterization of blast furnace dust resulting from the processing of cast iron, a useful analysis for this material to be reintroduced into the agglomeration process. From the obtained results it was found that the blast furnace dust contains significant amounts of SiO2 in fine granular form (

In most situations, for the proper design of a gerotor pump, numerous parameters must be taken into account: the pump geometry, the properties of the materials from which the pumps are made (Young's modulus, Poisson's coefficient, friction coefficients, etc.), the hydraulic characteristics of the circulated fluids (fluid density, kinematic viscosity, etc.), the working performance of the pump (speed ranges, pressure, flow rate, etc.), with greater or lesser influence on volumetric efficiency, work capacity, or energy consumption. The paper presents a study regarding the inspection of the reciprocally enwrapping surfaces of the gerotor pumps using a three-dimensional measurement technique specific to reverse engineering, which involves 3D scanning of the pump components in gearing movement. The components were measured by means of a specific software (GOM Inspect) and compared, by overlap, with the CAD models made with the help of CATIA software (CATIA V5R21). At the same time, an analytical calculation algorithm was developed for the complementarity of virtual representations. Finally, the advantages of the reverse engineering technique compared to the developed theoretical algorithm and traditional CAD design are presented. [ABSTRACT FROM AUTHOR]

Recognizing the crucial role that transport and lifting installations play in various sectors, including industry, construction, and extraction, as well as in mechanizing loading and unloading operations, and the movement of equipment or materials, special attention must be oriented to the diversification and the production of these installations by using the most advanced technologies. The paper presents some operating principles and characteristics of a lifting and transport Spider Crane installation equipment. This installation is considered a more economical and efficient alternative to traditional cranes for works where lifting requirements are below certain limits and significant height. Thus, an analysis of the hydraulic lifting system was carried out, based on the calculation of hydraulic fluid flows for the drive pumps. Also, was evaluated the specific speeds and forces of the hydraulic cylinders, a mechanical analysis of the clamping system with hook, as well as a finite element analysis of some mechanical and hydraulic components. [ABSTRACT FROM AUTHOR]

Refill friction stir spot welding (RFSSW) technology is a solid-state joint that can replace conventional welding or riveting processes in aerospace applications. The quality of the new welding process is directly influenced by the welding parameters selected. A finite element analysis was performed to understand the complexity of the thermomechanical phenomena during this welding process, validated by controlled experiments. An optimization model using neural networks was developed based on 98 parameter sets resulting from changing 3 welding parameters, namely pin penetration depth, pin rotation speed, and retention time. Ten parameter sets were used to verify the learning results of the optimization model. The 10 results were drawn to correspond to a uniform distribution over the training domain, with the aim of avoiding areas that might have contained distortions. The maximum temperature and normal stress reached at the end of the welding process were considered output data. [ABSTRACT FROM AUTHOR]

In industrial practice, is sometimes needed to manufacture specific parts without blueprints. This part of engineering process is known as reverse engineering. Usually, this assumes that an existing piece is measured or scanned and based on this result is made a new part. If the part can be machined with universal cutting tools the manufacturing process don't rise problems, but in case of parts which needs specific tools, these must be designed to be suitable for machining the piece. In this paper, a tool profiling algorithm is proposed, which is based on the capacity to measure and represent some surfaces in a methodical cloud of points form. The proposed profiling algorithm is based on the "virtual pole" method. This method is used together with the intermediate surface theorem for profiling tools characterized by a helical primary peripheral surface. This article will represent a continuation of a research which was been published in 2021, in Bulletin of Polytechnic Institute from Jassy. In that published article, the profiling of the hob mill tool was presented in a theoretical way and the "virtual pole" theorem was applied for an any type of profiles. The proposed algorithm allowed the determination of the tool's profile reciprocally enveloping with a piece's profile known in discrete form. Now, in this paper, the discrete form profile will represent exactly a cycloidal disk from a cycloidal reducer whose coordinates were determined using specific reverse engineering processes. Considering that the determination of the relative movements between the tool and the part, as well as the determination of the enveloping condition are relatively complicated and can be a source of errors, the purpose of this work is to highlight the advantages of the "virtual pole" method compared to the other specific methods of tool profiling that generate by enwrapping. At the same time, it is investigated if the "virtual pole" method can provide a support for the identification of the intermediate surface, with the help of graphic design environments, for profiling, in this case, the worm tools, since the "virtual pole" method cannot be applied as such in the case of disk-type tools, worm tools and cylindricalfrontal tools, due to the fact that the theorem is intended for the study of planar gearing. The advantages of using the "virtual pole" method are obvious compared to the classical tool profiling methods. The results demonstrated the accuracy of the method, by the fact that, using the "virtual pole" method, the calculation time for profiling the hob mill tool for generating a profile known in discrete form, namely the profile of the cycloidal disk, is significantly reduced. [ABSTRACT FROM AUTHOR]

The “virtual pole” method allows profiling of the cutting tools that generate by rolling. This mode of generation is advantageous in terms of the accuracy of the geometric shape obtained. The mentioned method combines the analytical accuracy of profiling with a simplified calculation mode, compared to the established algorithms. The paper presents an application made on the basis of the “virtual pole” method, for the profiling of the gear shaped tool, designed to generate the bore of a bush with a K-profile. Based on this methodology, in house software was developed for the type of profile mentioned above. The program allows the numerical and graphical representation of the profile to be generated, the contact curve and the profile of the generating tool.

This paper presents the profiling of the hob mill designed to generate the active surface of the cam of a cycloidal reducer. The algorithm allows determining the active surface of the generating rack gear, which is reciprocally enveloping with the active surface of the cycloidal disk. The novelty of the algorithm, based on the determination of the intermediate surface, consists in the fact that an innovative method of determining this surface is used, called the "virtual pole" method. The method allows determining the enwrapping curve of an ordered curl of surfaces, generated in the rolling movement of two conjugated centrodes. Using the "virtual pole" method, the calculation time for tool profiling is significantly reduced and the disadvantage of the resulting error, small enough to be neglected from a technical point of view, is fully compensated by this reduction in calculation time. [ABSTRACT FROM AUTHOR]

This paper analyzes the front axle of the Mercedes AMG GT model, as so as the graphical representation of the axle and of the subassemblies of suspension system and steering system, using the AutoCAD and Autodesk Inventor software. The paper include the steps for made the 3D model of the front axle in order to highlight the advantages of suspension and steering system, the function of this systems and methods for manufacturing of these. The 3D model presents a suite of complex surfaces. This type of surfaces is often designed with non-analytical means. The main commands and options used in Autodesk Inventor software were presented and explained. All the component parts of the front axle were modelled and assembled according to their functional role. Finally, the models were rendered in order to have a realistic appearance.

The conical rotary compressor represents a solution for gases compression, for relatively small flow, in conditions of a superior energetic efficiency. Although the theoretical solution for the helical conical compressor was elaborated decades ago, a viable technology solution become possible at industrial level only after the development of machine tools with numerically controlled axes. In this paper is proposed a study, analytical and graphical, concerning the geometry of conical rotary compressor’s rotors, modelled by rapid prototyping technology. The propose modelling allow to elaborate various constructive forms for conical compressor’s rotors.

The paper presents an algorithm for profiling the hob tool designed to generate by plastic deformation the worm shafts from the composition of worm-wheel gear type, used in the seat adjustment mechanisms of some Audi and Mercedes cars. The active surface of the hob tool is a cylindrical helical surface of constant pitch. Two such tandem tools are used for deformation, the semi-finished product being positioned between them. During generation, the tools rotate around their own axes, which, combined with their helical surface, causes a helical movement of the blank. The active surfaces of the tools are mutually winding on the helical flanks of the generated worm. In the paper, two applications were developed for the generation of worms whose dimensions were determined by 3D scanning. [ABSTRACT FROM AUTHOR]

The hob mill is a cutting tool with a wide application for generation in machining of splined shafts. A method for profiling the hob mill for generation of square splines is presented in this paper. The analytical development was done based on a complementary theorem of surface enwrapping — the method of generating trajectories. A numerical application for a standardized spline shaft is presented. Based on the same theorem is presented a graphical application, developed in the CATIA design environment, for profiling the hob mill which generated standardised square splines.

Recently, 3D measurement systems have developed more and more in various fields. With the help of 3D measuring systems, the measurement time in design, manufacture, assembly and production is substantially reduced. In this paper, it is proposed to redesign two pieces of a helical pump (driver and driven screws) based on numerical models obtained by scanning. These models are obtained based on the processing of point clouds resulting from the 3D scanning of the respective pieces. After completing the actual scanning process, the numerical models were measured using specific software to determine the dimensional characteristics and their modeling was performed in a computer-aided design program. Subsequently, the inspection was performed by overlapping the scanned model and the CAD model of each piece, in order to be able to compare the analytical models with the real pieces. This comparison allows to appreciate the degree to which the analytical model obtained by redesign corresponds to the real piece. In this way, the ability of future pieces obtained based on the analytical model to be able to accomplish the desired functional role can be appreciated. [ABSTRACT FROM AUTHOR]

The processing of the piece surfaces involves the transformation of the blank into a piece, the defining characteristics of the surfaces (the form, dimensions, deviations, etc.), depending to a large extent on the parameters of the generated processes of the surfaces. Generating surfaces by enveloping represents a complex problem, this mode of generating being a constant concern of researchers due to its advantages. A very important issue is the cutting edge profiling of the future tool, which will generate the wanted profile of the piece. Throughout time, researchers have studied the problems of enveloping surfaces and stated theorems related to them, based on which practical solutions have been conceive to determine the generating and generated surfaces form. The paper presents an overview on study methods for reciprocally enwrapping surfaces, as well as methods for profiling tools for generating helical surfaces by the kinematic method and by the method of decomposing the helical movement. This review can represent a basis for future research articles and projects. [ABSTRACT FROM AUTHOR]

Situations encountered in "reverse engineering" are relatively common in which, to address a problem of profiling generating tools for processing an orderly curl of surfaces (cylindrical or helical teeth), data known by measuring the existing product are used. The surface numerical representation can be done in the form of a points cloud. The profiling algorithm proposed in the paper is based on the possibility of measuring surfaces and their representation through an ordered cloud of points. The algorithm uses the complementary theorem of the virtual pole, for profiling the rack tool generating a piece that has an ordered curl of profiles. The methodology is not limited to the profiling of the rack tool but can be extended to the problem of profiling the primary peripheral surface of some screw-type tools, generating the ordered curl of surfaces. The paper also presents a numerical application developed based on a specific software product. [ABSTRACT FROM AUTHOR]

The technological design of devices has a significant share in the industrial field and, therefore, any study that highlights, through concrete examples, the main issues regarding the design of devices used, especially in the machine building industry, is welcome. The paper presents three fixturing devices specialized for the drilling operation of some technical pieces encountered in the field of hydraulic drives - spool valve, fixing clamp and flange support ventilation self-cleaning filter system. Both the pieces and the devices were made with the help of Autodesk Inventor program, a software package that streamlines as concrete and precise as possible the 3D modeling of solids. [ABSTRACT FROM AUTHOR]

Hydroforming processes have become increasingly popular in recent years, due to the increasing demand for light parts in various fields, such as the automotive, aircraft and aerospace industries. This technology is relatively new compared to other processing procedures, such as lamination, forging or stamping. This paper presents some basic concepts about hydroforming procedures, as well as 3D graphical modeling of a hydro-mechanical drawing die made in the Autodesk Inventor software program. [ABSTRACT FROM AUTHOR]

• For the points measured in the initial order the length of the route is 211 mm. • The length's route is 197 mm for heuristic method and 199 for the approximate one. • If heuristic algorithm is applied the improvement is 6.8% of the route length. • If approximate algorithm is applied the improvement is 5.6% of the route length. • The path length for the approximate method versus the heuristic one grows with 1.3%. The most evident characteristics of body components used in automotive industries are two overall dimensions with much higher values compared to a third one, as well as the relatively uniform apportion of functional elements on the surface of the workpiece. During the inspection process, these characteristics determine the active measuring element to pass greater distances between the measuring areas, in comparison to the distances required for the effective measurement. Heuristic and approximate methods for measuring path optimization have the advantage of finding a solution making fewer operations, and the found solution differs from the optimal solution with no more than 2–3%. In the present paper, optimization algorithms based on the matrix relaxation method and nearest neighbor method were imagined and applied. These algorithms have served as a basis for developing a software. This software allows the optimization of the measurement path for car body parts which characterized by areas where the inspection is carried out, relatively uniformly apportioned over the surface of the workpiece. [ABSTRACT FROM AUTHOR]

The reliability of the products, determined by measuring and estimating quality characteristics, plays a decisive role in the strategy of the economic evolution. In the execution of rigid road clothing, traditional materials are used, which are found in nature (stone, sand, cover aggregate etc.). Blended with binders, the resulting structures must respect specific wellestablished resistors, obtained in special production stations. In order to determine the quality of any material used in practice, first of all, it is necessary to run tests on it in laboratories equipped with specific apparatus. This paper presents a comparative study on the bending behaviour of the road concrete class BcR-4.5 and BcR-5.0, on the KD-KL 300/R hydraulic dual piston test machine. The bending strength was calculated, under the action of different forces, comparing the experimental values with the values obtained from a finite element analysis. [ABSTRACT FROM AUTHOR]

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Dimensional accuracy of the cast parts strongly depends on cooling history which is mainly related with casting parameters. Cooling history refers also to heat transfer coefficient through cast/mold interface. This is a very difficult task for researchers to deal with, considering the difficulty in estimating and controlling the heat quantity which crosses the interface and mold wall going to ambient. The paper presents the estimation of heat transfer coefficient evolution during solidification of a hollow cylinder cast part. Artificial neural networks are very useful and reliable tools in prediction and estimation of casting parameters. Even if there are many previous relevant studies concerning the heat transfer coefficient determination at the cast/mold interface, researchers still deal with many uncertainties related to application of numerical developed models to a variety of dimensions and geometry. [ABSTRACT FROM AUTHOR]

Hydraulic cylinders are subassemblies of hydrostatic equipment which convert the hydrostatic energy to mechanical energy. This is possible by transforming the hydraulic parameters such as pressure and flow of the incoming fluid to parameters associated with translation, force and speed. The hydraulic cylinders usually have, as active element, a subassembly composed from a rod and one or more pistons which translates inside a working cylinder. This paper presents the functioning analysis at parallel hydraulic coupling of 3 single-rod double-acting hydraulic cylinders with different diameters and strokes. This is made in order to calculate the corresponding forces and speeds for both displacement directions of rod-piston subassembly. [ABSTRACT FROM AUTHOR]

The modelling of a curl of surfaces associated with a pair of rolling centrodes, when it is known the profile of the rack-gear's teeth profile, by direct measuring, as a coordinate matrix, has as goal the determining of the generating quality for an imposed kinematics of the relative motion of tool regarding the blank. In this way, it is possible to determine the generating geometrical error, as a base of the total error. The generation modelling allows highlighting the potential errors of the generating tool, in order to correct its profile, prior to using the tool in machining process. A method developed in CATIA is proposed, based on a new method, namely the method of "relative generating trajectories". The analytical foundation is presented, as so as an application for knows models of rack-gear type tools used on Maag teething machines. [ABSTRACT FROM AUTHOR]

The compressor rotors usually are helical surfaces with constant pitch and are composed of crossing profiles. Frequently, for repair operations, the reconstruction necessity occurs for one or both of the worms, drive and driven, from the helical compressors gear. The theoretical helical surface of the worm is being substituted by an assembly of helical lines which together with crossing profiles forms points cloud resulted from measuring leads to a polyhedral expression of the flank rotor. Numerically, this surface type is expressed by a coordinate array which shows its discrete image. The profiling of cutting tool bounded by a revolution surface reciprocally enveloping with the substitutive surface of the helical one represents a special problem. In this paper is proposed an algorithm for polyhedral expression of the helical surface previously determined by reverse engineering methods and an algorithm for the determination of the specific enveloping condition at contact with a discrete surface. It is presented an example for a compressor rotor measured on a 3D measuring machine, the algorithm for the transformation of the gathered points cloud in a surface with polyhedral expression. Given these conditions there were determined the enveloping condition and the axial section of the side mill. [ABSTRACT FROM AUTHOR]

In this paper, we present a graphical method, developed in CATIA environment, based on the method of substituting circles family and dedicated to profile pinion cutters for generating interior surfaces. Hereby, the family of substituting circles associated to the worked piece (the profile to be generated) is determined at the same time to the curve transposed, in the rolling motion, to the tool centrode. After finding the position of the contact points between the generated profile and the family circles, we can determine, in the transposed family, the locus of the points from the reciprocal enwrapping profile -- the pinion cutter profile. The paper also includes two method applications, for generating a hole with square transversal section, and a pump stator with trapezoidal profile. Comparisons between the profiling results when using the graphical method, versus an analytical method have also been realized. The results are proving the coincidence between the two profiles determined as above, on one hand, and both rapidity and precision of the graphical method, on the other hand. [ABSTRACT FROM AUTHOR]

Decrease of the unitary energetic load along the cutting edge with variable working angle, by increasing of the number of cutting edges in the construction of the helical drill, and, in the same time, the accomplishment of an evenness unitary energetic load may be assumptions for decreasing of the temperature of the tool cutting edge at its periphery. This will leads to the decreasing of the tool wear rate, hence the increasing of the tool's durability. In this paper, we present experimental research on curved cutting edge drills, regarding the speed-durability dependence in processing carbon steel. We observed that durability of curved cutting edge drills is superior to durability of standard drills for the same working conditions. [ABSTRACT FROM AUTHOR]

In the paper, for a specific profile, the localization of contact points in multipoint forming is analysed. For this, some simulation models using the finite element method were developed. A program for contact points calculation between the part and the tool active elements was designed. For a configuration of the multipoint deformation tool without interpolator, the correlation between the contact points distribution and the localized deformation is discussed. Then in the case of the multipoint deformation tool with interpolator, the part quality is analysed in terms of surface quality, part profile deviation and elastic recovery. The results show, in the cases of studied profiles, the presence of the spring-forward which increase when the part profile angles are increasing, to the same interpolator thickness. [ABSTRACT FROM AUTHOR]

In defining the process -- the complete combination through which the hired personnel, the methods, tool machines and cutting tools are involved in providing a product or service, we have to adjust quality indications regarding function performance of the cutting tool in its operational environment. The paper presents aspects on how to establish the precision with which a CNC machining center executes movements on the X and Y axis, while processing square plates, by drilling approximately 900 holes, on a total processing length of 45m, using drills with different diameters and variable cutting parameters (cutting speed and feed). [ABSTRACT FROM AUTHOR]

This paper presents a simplified algorithm for the profiling of the rack gear tool to generate the active profile associated with rolling centrodes. The algorithm is based on the enveloping surfaces principles and reduces the computational problem by proposing an approximate representation of tool’s profile using only three or four points on the profile to be generated by using Bezier representations of the surfaces. The algorithm computes the coefficients of a Bezier substitution polynomial instead of computing hundreds of points on the active profile. This simplifies the solution methodology and requires only a limited number of points along the profile to be generated. The algorithm is computationally efficient and can also be used in the case when the active profile to be generated is physically measured at a few points. Examples include mill tools, splined shafts, and gears. [ABSTRACT FROM AUTHOR]