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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]

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]

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]