Papers by Keyword: Ingot Casting

Abstract: It is investigated that effect of steel strip-feeding ratio and superheat degree of molten steel on solidification structure of ingot by the steel strip-feeding experiment in the mold. The results show that: at the same superheat, with the increase of feeding ratio, the area proportion of equiaxed grain zone increases and the average size of equiaxed grain decreases, and at the same feeding ratio, the higher the superheat is, the smaller the proportion of equiaxed grain zone is, and the larger the average grain size is.

Abstract: The electromagnetic stirring technique was used in the experiment to prepare the ingot casting. After comparing the conventional production by the means of ingot casting through electromagnetic field production, the results showed that the solidification of crystal was significantly influenced by the electromagnetic power. As the powers of the agitator increasesed from 0 KW to 20 KW, the refined grain size could be easily detected. That means, the length of the columnar crystal had shortened and isometric crystal had increased dramatically. From the phase transformation we can see that the pearlite and ferrite were distributed much more uniform than the original specimens. The results of the test showed that strengthening electromagnetic field is one of the most important methods to modify the internal crystal morphology. In conclusion, the electromagnetic stirring played a key role in ingot casting.

Abstract: Producing low-dross ingots has been a long-term goal in aluminium cast houses. The patented CASTfill technology [1] is a low-dross and high-productivity pouring system developed to fulfil this demand. This paper describes the research methods used during the development of CASTfill; now in service at Boyne Smelters Limited (BSL) since August 2009. The importance of combining scientific modelling and testing procedures with process operability, maintainability and durability to ensure the success of new technology in a production facility is also highlighted. Ingot assessments showed that the latest CASTfill design greatly reduced dross generated during mould filling. Improved ingot packaging and reduced variation of ingot weights were also observed as the results of a more tranquil flow of molten aluminium through CASTfill and its uniquely modular design.

Abstract: Physical modeling of argon shroud was carried out using a 2D 1:1 scaled model in order to gain the protection effect in steel casting. The speed field of protective gas around the steel steam was measured by PIV technique. The oxygen distribution was measured by an oxygen sensor. The main findings are following: (1)The distance between the ladle and the collar should be minimized to reduce the oxygen entrainment.(2)For single inlet, the oxygen contents were lower in the case of horizontal gas inlet than vertical gas inlet.(3)A dual gas inlet configuration would be more effective than a single inlet in ordinary operation conditions.

Abstract: Tomago Aluminium experienced problems with the boiling of cooling water in ingot casting machines, where water splashed onto molten aluminium after mould filling. The boiling problem was particularly severe when new standard moulds were installed. This paper describes the experiments and modelling employed to analyse and identify the cause of the problem and based on the results, modifications to mould geometry were suggested. Subsequent testing in lab and field trials showed that the boiling was suppressed. The first set of modified moulds in service at Tomago Aluminium showed mould life was improved as predicted. Other issues with the modified mould design, which arose in service, are also discussed.