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The analysis of the issue of monitoring and diagnostics of surface of narrow crystallizer’s desks. There is described the development and the achieved laboratory results based on laser object surface scanning. The diagnostic system which is currently creating will be part of management systems to support service life of mould as a part of continuous steel casting device. The emergence of weariness is caused by many factors, influences and processes that act and run directly on the device, its individual parts, through its operation.

In the paper, presented are results of a research on influence of compaction degree on dielectric properties of components of moulding sands. During recent years, intensive research works on possibilities of using microwave heating in foundry technique are carried-out. However, introduction of such innovative, environment-friendly and efficient heating processes to foundry technologies is accompanied by a shortage of basic knowledge about behaviour of components of moulding sands in microwave field. In this case, of particular importance becomes knowledge of electrical properties of components of moulding and core sands, i.e. their permittivity εr and dielectric loss factor tgδ that characterise efficiency of absorbing electromagnetic radiation and thus prove effectiveness of the heating process.

The paper deals with research of the heat transfer in the mould of continuous casting and the thermal boundary condition determination using combination of measurement and the inverse technique of numerical simulation. An average heat flux in the mould is calculated from measured parameters of mould cooling water. Layout of the heat flux at the mould working surface is derived by the original experimental and numerical simulation procedure, which is based on measuring temperatures in the mould walls and solving a numerical inverse problem including stress and shrinkage, using the software package Procast. A database of the heat flux layouts was built for various values of casting speed and steel chemical composition for purpose of determination the boundary condition for on-line modeling.

The source of compressive stresses lies in the structure of quartz sand. By reaching the critical temperature (from 560 to 580 °C), the quartz sand grains increase volume. The increase in volume causes the movement of surrounding grains of sand. In this paper, it is shown by the dilatometric investigations of different granulometric compositions of quartz sands how the granulometric composition affects the size of the mould dilatation caused by heating during pouring of the melt.

This report describes research of thermal processes in primary cooling area in terms of assessment of temperature profiles and determination of thermal flows of the mould. Even formation of casting crust in mould depends on its thermal work, related to distribution of temperature along the height of individual mould walls, which affects operation of the whole continuous casting machine (CCM) in fundamental way. Ideal temperature profile along the height of the mould assures even removal of heat from a blank and it is an essential prerequisite of high quality production. A separate part has been dedicated to ways of preventing breakouts with the use of simulation of kinetics of the mould temperature field. Some of the achieved results are shown on particular examples.

The analysis of the issue of monitoring and diagnostics of surface of narrow crystallizer's desks. There is described the development and the achieved laboratory results based on laser object surface scanning. The diagnostic system which is currently creating will be part of management systems to support service life of mould as a part of continuous steel casting device. The emergence of weariness is caused by many factors, influences and processes that act and run directly on the device, its individual parts, through its operation. [ABSTRACT FROM AUTHOR]

In the paper, presented are results of a research on influence of compaction degree on dielectric properties of components of moulding sands. During recent years, intensive research works on possibilities of using microwave heating in foundry technique are carried-out. However, introduction of such innovative, environment-friendly and efficient heating processes to foundry technologies is accompanied by a shortage of basic knowledge about behaviour of components of moulding sands in microwave field. In this case, of particular importance becomes knowledge of electrical properties of components of moulding and core sands, i.e. their permittivity εr and dielectric loss factor tgδ that characterise efficiency of absorbing electromagnetic radiation and thus prove effectiveness of the heating process. [ABSTRACT FROM AUTHOR]

Paper is focused on the observation of the conditions causing defects origin in continuously cast billets in the first phase of solidification and shell formation in the mould. Work is also focused on the area of casting failures. Experiences were aimed at steel preparation for casting from the viewpoint of desoxidation and modification of inclusions, facility influence on solidification and formation of shell, influence of the taper of the mould, and on vibrations influence and origin within primary cooling system – oscillation mechanism – mould. The method of measurement was tested, incl. the analysis of acoustic spectrum for phenomena assessment within continuous casting. Conclusions resulted in modification and changes of shapes of moulds, incl. casting technology of round billets.

The paper deals with research of the heat transfer in the mould of continuous casting and the thermal boundary condition determination using combination of measurement and the inverse technique of numerical simulation. An average heat flux in the mould is calculated from measured parameters of mould cooling water. Layout of the heat flux at the mould working surface is derived by the original experimental and numerical simulation procedure, which is based on measuring temperatures in the mould walls and solving a numerical inverse problem including stress and shrinkage, using the software package Procast. A database of the heat flux layouts was built for various values of casting speed and steel chemical composition for purpose of determination the boundary condition for on-line modelling. [ABSTRACT FROM AUTHOR]

This report describes research of thermal processes in primary cooling area in terms of assessment of temperature profiles and determination of thermal flows of the mould. Even formation of casting crust in mould depends on its thermal work, related to distribution of temperature along the height of individual mould walls, which affects operation of the whole continuous casting machine (CCM) in fundamental way. Ideal temperature profile along the height of the mould assures even removal of heat from a blank and it is an essential prerequisite of high quality production. A separate part has been dedicated to ways of preventing breakouts with the use of simulation of kinetics of the mould temperature field. Some of the achieved results are shown on particular examples. [ABSTRACT FROM AUTHOR]

The source of compressive stresses lies in the structure of quartz sand. By reaching the critical temperature (from 560 to 580 °C), the quartz sand grains increase volume. The increase in volume causes the movement of surrounding grains of sand. In this paper, it is shown by the dilatometric investigations of different granulometric compositions of quartz sands how the granulometric composition affects the size of the mould dilatation caused by heating during pouring of the melt. [ABSTRACT FROM AUTHOR]

Paper is focused on the observation of the conditions causing defects origin in continuously cast billets in the first phase of solidification and shell formation in the mould. Work is also focused on the area of casting failures. Experiences were aimed at steel preparation for casting from the viewpoint of desoxidation and modification of inclusions, facility influence on solidification and formation of shell, influence of the taper of the mould, and on vibrations influence and origin within primary cooling system - oscillation mechanism - mould. The method of measurement was tested, incl. the analysis of acoustic spectrum for phenomena assessment within continuous casting. Conclusions resulted in modification and changes of shapes of moulds, incl. casting technology of round billets. [ABSTRACT FROM AUTHOR]