The optimization of the state of welding parameters to obtain metalic structures from the OL 52.4K steel

The metallic structures realized from OL 52.4k have a very wide use, but they are used especially in case of tools used in mining plants. Due to the important constraints these welded structures are submitted into practice, it is very important to determine a set of optimal parameters of the welding system, so the obtained welded joints have an tensile stress Rm as big as possible. Among the experimental research there were obtained a series of results which, by statistically processing, it has been allowed the determination of a set of mathematical models which offers the dependence of tensile stress of welded joints in function of the welding system parameters

Validation of the finite element method (FEM) in case of reconditioning by welding applied to crankshafts

This paper presents the results of the practical trials carried out based on the calculation assumptions considered within the FEM of the reconditioning by welding of a crankshaft used in the automotive industry. For the validation of the analytical model it was considered the influence of the crankshaft fixing possibility as well as the influence of preheating temperatures on the structure of the deposited zone

The influence of the reconditioning by welding processes on the hardness of crankshafts in the automotive industry

One of the aims of our modern society is to reduce the car maintenance costs. The part that most frequently breaks down in the engine block is the crankshaft - in the main journal and crankpin journal areas. This paper presents the effects of welding inert-gas (WIG) and shielded metal arc welding (SMAW) on the hardness of the material in the zones subject to reconditioning, more specifically the hardness values in the deposited material layer, in the fusion line and the heat-affected zone (HAZ)

Finite element type of stress analysis for parts based on S235 JR steel welding

The determination of static and/or variable stress, in case of complex shaped welded structures is hard to achieve. One solution, though, is the use of finite element method, implemented by means of various specialized software. Nowadays, this method has become very popular due to its high precision of data obtained through both research and finite element analysis. Hence, the present paper deals with the modelling of the pull-out behaviour of concave and convex welded joints through finite element method

Assessment of air pollutants produced by industrial activity from an aluminium alloys foundry

The industrial activity in non-ferrous alloys foundries leads to the elimination of the pollutants in the atmosphere that may have adverse effects on the environment and human health. This paper presents an evaluation of the pollutantemissions resulting from an aluminium foundry starting from data on concentrations and pollutant massflow rates estimated for each phase of the technological process and on measured ambient levels for the area of influence of the objective to study

The effects of reconditioning by welding of crankshafts in automotive industry

The reconditioning by welding process applied to the crankshafts in the automotive industry can be carried out by using various reconditioning technologies that are based on different welding parameters and processes. This paper presents a comparison between Shielded Metal Arc Welding (SMAW) and Welding in Gas (WIG) reconditioning processes from the perspective of the metallographic analysis conducted on the zones resulted after the depositing process. The heat cycle resulted during the two welding processes influences in a different manner the welding behavior of the base material due to the occurrence of micro-structural changes in the main zones of the deposit. The occurred structural changes may influence to a significant degree the operating behavior of the structures repaired by welding

Research of the ultrasonic testing parts reconditioned by welding

The paper presents the results obtained following the nondestructive ultrasonic testing of crankpin shaft of a crankshaft that were reconditioned by welding. After the ultrasonic testing, the reconditioned samples were cut and subjected to visual testing and microstructure examination. When the results obtained following the nondestructive tests were analyzed, it was observed that the ultrasonic nondestructive testing method is an efficient way to determine the conformity of the areas that were reconditioned by welding