ADSTEFAN is a casting simulation system which predicts the casting defects that occur in fields related to the production of base stocks.

Hitachi Industry & Control Solutions has introduced the casting simulation system ADSTEFAN Ver. 2019. ADSTEFAN is newly equipped with an in-mould gas flow analysis function for sand casting, as well as the ability to improve accuracy of existing functions and reduce time required for analysis. It enables simulations, that are closer to reality than conventional methods, which considers the motion of the gas generated during sand casting inside the moulds.

ADSTEFAN is a casting simulation system which predicts the casting defects that occur in fields related to the production of base stocks. It simulates flow of molten metals into the moulds and state of solidification, which are not directly visible, and visualizes the process as three-dimensional images. With this configuration, the new system enables a decline in the number of trial manufacturers supporting the reduction of development term and improvement of product quality.

Recently, the development of products with new concepts has accelerated even in the automobile and transportation industries, infrastructure industry, etc. Under these circumstances, for the parts constituting the products, it is necessary that the shape should be more complex, weight be reduced, durability be improved and delivery time be shortened. The accuracy and efficiency of the simulation are expected to improve in the process of casting simulation. The users of ADSTEFAN request functions to simulate the motion of gases generated due to the combustion of binders due to the heat from the molten metal, because such gases cause casting defects.

In response to the above user demand, Hitachi Industry & Control developed the in-mould gas flow analysis function, which simulates the motion of gases generated inside the moulds during the solidification of casting, through joint research with the Anzai Laboratory of Tohoku University. Further, Hitachi Industry & Control implemented demonstrations in the Research Center for Casting Technology of Iwate University, which boasts knowledge about sand casting and a large number of test devices.
As an expansion of the existing functions, the function for rotating mobile objects has been added and the accuracy of tracking the behaviour of markers for analysis of fluid flow has been improved, making it possible to carry out simulations that are closer to reality. ADSTEFAN also has a function for shortening the analysis time by increasing the speed processes.

With the above new functions and expansions, ADSTEFAN supports the further shortening of development time and improvement of product quality.ADSTEFAN Ver. 2019 offers the following advantages:

1.     In-mould gas flow analysis function: Hitachi Industry & Control has achieved analysis on the flow and the pressure of the combustion gas generated from the binder inside the sand moulds in sand casting. The system predicts casting defects that can easily occur at locations where the gas pressure is high, supporting product quality for casting.

2.    Mobile object considering function: Rotational movement has been added to the moving state control methods for the ladle, plunger tip, stopper and moulds that may be influential to theflow and temperature change of the molten metals. Fluid flow analysis closer to the actual casting is achieved using this function in combination with the parallel movement.

3.    Marker function: The marker function is for displaying oxide films and broken chill layers that may cause casting defects as coloured objects. This time, the dedicated physical model for tracking the status of generationof oxide films and broken chill layers and their motions in the molten metal have been introduced, and it is possible to perform simulations closer to actual casting.

4.    Function expansion: Calculation scope designation function and the integrated processing of data on analysis results. The number of times required for input and output of files is reduced by adding the calculation scope designation function for limiting the portion to be analysed and by performing integration processes for the data of the analysis results generated when parallel analysis is performed.With these functions, the time taken for visualisation of analysis results is reduced, specifically, the total computation time by 44 per cent for fluid flow analysis, and by 36 per cent for solidification analysis.