The repair of foundry defects in steel castings using welding technology

Use of welding technology for the repair of steel castings is particularly common in two areas. These include weld surfacing of protrusions that remained incomplete after casting, or filling the surface defects (cavities). These defects are more common for steel casting than for graphite cast iron, due to the lower fluidity of steel. This article describes a suitable technological process of repairing the defects on the casting using the welding technology. A specimen produced for this purpose was prepared by carving a groove into a cast steel plate 20 GL, which was then filled with a weld metal using MAG (135) technology. The following evaluation of the basic characteristics of the repaired site point to the suitability of the selected technological parameters of the repair procedure. Metallographic evaluation was carried out, further evaluation of mechanical properties by tensile test, bend test and Vickers hardness test. The proposed methodology for the evaluation repair of foundry defects in steel castings also meets the requirements for the approval of welding procedures in accordance with the relevant valid legislation.Web of Science18218017

Numerical simulation of dissimilar weld joint in SYSWELD simulation software

Zavareni spojevi od različitih materijala podliježu čestim kvarovima zbog raznih faktora. Postoji nekoliko metoda koje se mogu primijeniti za predviđanje kvarova, a među njima vrlo važnu ulogu ima predviđanje zaostalih naprezanja i tvrdoće zavara. Tijekom dizajniranja konstrukcije, postoji mogućnost predviđanja zaostalog naprezanja numeričkom simulacijom varenja koja može služiti za prevenciju kvara. U ovom radu zaostala naprezanja zavarenog spoja X5CrNi18-10/S355J2H od različitih materijala predviđena su programom SYSWELD nakon optimizacije postupka zavarivanja eksperimentalno dobivenim toplinskim ponašanjem. Čudesni alat za tvrdoću iz tog programa upotrjebljen je za predviđanje tvrdoće zavarenog spoja.Dissimilar weld joints are prone to frequent failures caused by many factors. Several methods might be used for prediction of the failures, from which prediction of the residual stresses and weld joint hardness plays a very important role. During the construction design, there is a possibility to predict residual stress by welding numerical simulation that may serve as the failure prevention. In presented article, residual stresses of dissimilar X5CrNi18-10/S355J2H weld joint were predicted by SYSWELD software after optimization of welding process by experimentally obtained thermal behaviour. The hardness wizard tool of the programme was employed for prediction of the weld joint hardness

Identifying the cause of cutting tool failure by using simulation software

The article is focused on the construction problems of cutting tools designed for manufacturing components in high numbers. Analysis of the tool with low lifetime is provided with the use of simulation software to detect the causes of the tool failure. Parameters of the simulation are close to the real conditions of the tool in production. The results from the simulation indicate that the bending moment occurs in the tool because of forces which have opposite direction on different areas. On these basis technological adjustments are made. These adjustments are also analysed by using simulation software

Identifying the cause of cutting tool failure by using simulation software

The article is focused on the construction problems of cutting tools designed for manufacturing components in high numbers. Analysis of the tool with low lifetime is provided with the use of simulation software to detect the causes of the tool failure. Parameters of the simulation are close to the real conditions of the tool in production. The results from the simulation indicate that the bending moment occurs in the tool because of forces which have opposite direction on different areas. On these basis technological adjustments are made. These adjustments are also analysed by using simulation software

Lap weld joint modelling and simulation of welding in programme SYSWELD

Simulations of the welding process for applications of practice using SYSWELD are presented. This paper presents simulation of welding in the repair of high-pressure gas pipeline with steel sleeve with composite filling. Material of experimental sample was steel S355. The simulations in SYSWELD divided in to two parts: the thermal simulation followed by the mechanical simulation. The results of the numerical model, which are listed in article are compared to real experiments

Schweisssimulation bei der Reparatur der Gasleitungen mit Stahlhülse

Teoretická část článku se zabývá základními informacemi o opravách plynovodních potrubí pomocí ocelových objímek a simulačním systémem SYSWELD. Experimentální část zahrnuje analýzu okrajových podmínek pro proces simulace dvouvrstvého obvodového svaru. Součástí analýzy okrajových podmínek je vyhodnocení svařovacích parametrů, rychlosti svařování, teplotních cyklů, makrostrukturální rozbor a její digitalizace. Využitím těchto okrajových podmínek byl nasimulován proces svařování v systému SYSWELD. Výsledky simulace jsou vykresleny pomoci teplotních polí a teplotních cyklů.Część teoretyczna artykułu dotyczy podstawowych informacji na temat naprawy gazociągu z użyciem stalowych tulei i przy pomocy systemu symulacji SYSWELD. Część doświadczalna obejmuje analizę granicznych warunków spawania dwuprzebiegowego. Analiza obejmuje także ocenę parametrów spawania, prędkość spawania, cykle temperatury, analizę makrostrukturalną i jej digitalizację. W wyniku zastosowania warunków granicznych dokonano symulacji procesu spawania w systemie SYSWELD .Wyniki symulacji zostały przedstawione za pomocą pól temperatury i cyklów temperatury.The theoretical part of the paper deals with basic information about repair of gas pipeline with steel repair sleeves and simulation programme SYSWELD. The experimental part includes analysis of boundary conditions in two-pass fillet welding joint. By analyzing the boundary conditions welding speed, temperature cycles, macrosctructural analysis and its digitization can be determined. Using these boundary conditions welding process in programme SYSWELD was simulated. The results of the simulation are illustrated by means of temperature fields and temperature cycles.Der theoretische Teil des Manuskripts beschäftigt sich mit grundlegenden Informationen über die Reparaturen der Gasleitungen mit Stahlhülsen und das Simulationsprogramm SYSWELD. Der experimentelleTeil umfasst die Analyse der Randbedingungen der Simulation des Doppelschichtschweißens. Teil der Analyse der Randbedingungen ist es, die Schweißparameter, Schweißgeschwindigkeit, Temperatur-Zyklen, makrostrukturelle Analyse und ihre Digitalisierung zu bewerten. Mit diesen Randbedingungen wurde der Schweißprozess im Programm SYSWELD simuliert. Die Ergebnisse der Simulation werden mit Hilfe von Temperaturfelder und Temperaturzyklen dargestellt

Lap weld joint modelling and simulation of welding in programme SYSWELD

Simulations of the welding process for applications of practice using SYSWELD are presented. This paper presents simulation of welding in the repair of high-pressure gas pipeline with steel sleeve with composite filling. Material of experimental sample was steel S355. The simulations in SYSWELD divided in to two parts: the thermal simulation followed by the mechanical simulation. The results of the numerical model, which are listed in article are compared to real experiments

Austenitic biomaterial cracks evaluation by advanced nondestructive techniques

The article deals with Non-Destructive Evaluation (NDE) of austenitic stainless steels. Eddy current, ultrasonic testing and non-contact magnetic field mapping methods are used for this purpose. ECA (Eddy Current Array) and TOFD (Time of Flight Diffraction) are methods that have become widely-used in the field of NDE and this is the reason for their utilization. Magnetic field mapping is nowadays an effective method of evaluation of surface-breaking defects mainly in ferromagnetic materials. The fluxgate sensor-based measurement is presented and discussed. The artificial fatigue and stress-corrosion material’s cracks are inspected. Experimental results are presented and discussed in this paper

Numerical simulation of a temperature field during multi-beads surface welding

The calculation results of the temperature field during multi-beads GMAW (Gas Metal Arc Welding) cladding of the S355 steel plate are presented in the paper. Numerical simulations were performed using the SysweldR program. Two of Goldak’s heat source models were chosen for calculating the temperature field for each weld bead. The original article achievement is, by selecting the right heat source model and heat loading of the finite elements, obtaining an irregular shape of the fusion zone. This irregular shape of the fusion zone is very complicated to obtain using other commercial programs for numerical welding simulation. The calculation results were verified by the dimensions (critical temperatures) of the heat affected zones (HAZ) determined in the experiment, obtaining a satisfactory agreement