Abstract The information age is characterized by ever-growing amounts of data surrounding us. By reproducing this data into usable knowledge we can start moving toward the knowledge age. Data mining is the science of transforming measurable information into usable knowledge. During the data mining process, the measurements pass through a chain of sophisticated transformations in order to acquire knowledge. Furthermore, in some applications the results are implemented as software solutions so that they can be continuously utilized. It is evident that the quality and amount of the knowledge formed is highly dependent on the transformations and the process applied. This thesis presents an application independent concept that can be used for managing the data mining process and implementing the acquired results as software applications. The developed concept is divided into two parts – solution formation and solution implementation. The first part presents a systematic way for finding a data mining solution from a set of measurement data. The developed approach allows for easier application of a variety of algorithms to the data, manages the work chain, and differentiates between the data mining tasks. The method is based on storage of the data between the main stages of the data mining process, where the different stages of the process are defined on the basis of the type of algorithms applied to the data. The efficiency of the process is demonstrated with a case study presenting new solutions for resistance spot welding quality control. The second part of the concept presents a component-based data mining application framework, called Smart Archive, designed for implementing the solution. The framework provides functionality that is common to most data mining applications and is especially suitable for implementing applications that process continuously acquired measurements. The work also proposes an efficient algorithm for utilizing cumulative measurement data in the history component of the framework. Using the framework, it is possible to build high-quality data mining applications with shorter development times by configuring the framework to process application-specific data. The efficiency of the framework is illustrated using a case study presenting the results and implementation principles of an application developed for predicting steel slab temperatures in a hot strip mill. In conclusion, this thesis presents a concept that proposes solutions for two fundamental issues of data mining, the creation of a working data mining solution from a set of measurement data and the implementation of it as a stand-alone application.

The carbon footprint from the iron, steel and other metal sectors has become a problem both environmentally and economically. The purpose of this report is to propose a concept of an electrified reheat furnace for the steel industry in the making of sheet metal. The aim is to reduce the environmental impact from the steel industry. The approach in this report has been to analyse relevant facts to propose a fully electrified concept. The concept is divided into two sections. The first section of the concept consists of a preheating furnace with the purpose to heat the slabs to 850 °C before it enters the second section. The preheating furnace contains 1447 – 2412 MoSi2 heating elements due to considering different efficiencies. The second section consists of 13 induction heating modules heating the slabs to a homogenous temperature of 1250 °C. By applying electrical heating in a walking beam furnace approximately 100 000 tonne carbon dioxide can be reduced annually. In conclusion, the proposed concept could be a feasible solution in order to avoid carbon emission and obtain the same production rate as the existing reheating furnaces. However, it is suggested that further investigations and analysis are performed regarding this concept to verify the total efficiency of the reheating furnace and to theoretically determine the required power input / Koldioxidutsläppen från järn, stål och andra metallindustrier har blivit ett problem både urmiljö och ekonomisk synpunkt. Syftet med denna rapport är att föreslå ett koncept av en heltelektrifierad uppvärmningsugn för stålindustrin i processen för att skapa plåt. Målet meddenna studie är att reducera stålindustrins påverkan på växthuseffekten. Metoden i denna rapport har varit att analysera relevant fakta för att sedan kunna föreslå ettkoncept av en helt elektrifierad ugn. Det föreslagna konceptet är uppdelad i två delar. Denförsta delen består av en förvärmningsugn med målet att värma stålet till 850 °C innan ståletgår in i den andra delen. Förvärmningsugnen består av 1447 – 2412 stycken MoSi2värmeelement med hänsyn till ugnens verkningsgrad. Den andra delen består utav 13 styckeninduktionsvärmemoduler som värmen stålet till en homogentemperatur på 1250 °C. Genomatt använda elektricitet för att värma ugnen minskar koldioxidutsläppen med 66 kg per tontillverkas stål. Sammanfattningsvis, det föreslagna konceptet kan vara en möjlig lösning för att minskakoldioxidutsläpp och samtidigt bibehålla samma produktionshastighet som existerandeuppvärmningsugnar. Däremot är det förslaget att vidare studier och analyser görs påkonceptet för att verifiera den totala verkningsgraden av ugnen och för att bestämma denexakta energiförbrukningen.

Furnaces that heat metal parts (blooms) prior to hot-working processes such as rolling or forging are called pre-forming reheat furnaces. In these furnaces, the fundamental idea is to heat the blooms to a prescribed temperature without very large temperature gradients in them. This is to ensure correct performance of the metal parts subsequent to reheating. Due to the elevated temperature in the furnace chamber, radiation is the dominant mode of heat transfer from the furnace to the bloom. In addition, there is convection heat transfer from the hot gases to the bloom. The heat transfer within the bloom is by conduction. In order to design a new furnace or to improve the performance of existing ones, the heat transfer analysis has to be done accurately. Given the complex geometry and large number of parameters encountered in the furnace, an analytical solution is difficult, and hence numerical modeling has to be resorted to. In the present work, a numerical technique for modelling the steady-state and transient heat transfer in a reheat furnace is developed. The work mainly involves the development of a radiation heat transfer analysis code for a reheat furnace, since a major part of the heat transfer in the furnace chamber is due to radiation from the roof and combustion gases. The code is modified from an existing finite volume method (FVM) based radiation heat transfer solver, The existing solver is a general purpose radiation heat transfer solver for enclosures and incorporates the following features: surface-to-surface radiation, gray absorbing-emitting medium in the enclosure, multiple reflections off the bounding walls, shadowing effects due to obstructions in the enclosure, diffuse reflection and enclosures with irregular geometry. As a part of the present work, it has now been extended to include the following features that characterise radiation heat transfer in the furnace chamber · Combination of specular and diffuse reflection as is the case with most real surfaces · Participating non-gray media, as the combustion gases in the furnace chamber exhibit highly spectral radiative characteristics Transient 2D conduction heat transfer within the metal part is then modelled using a FVM-based code. Radiation heat flux from the radiation model and convection heat flux calculated using existing correlations act as boundary conditions for the conduction model. A global iteration involving the radiation model and the conduction model is carried out for the overall solution. For the study, two types of reheat furnaces were chosen; the pusher-type furnace and the walking beam furnace. The difference in the heating process of the two furnaces implies that they have to be modelled differently. In the pusher-type furnace, the heating of the blooms is only from the hot roof and the gas. In the walking beam furnace, the heating is also from the hearth and the blooms adjacent to any given bloom. The model can predict the bloom residence time for any particular combination of furnace conditions and load dimensions. The effects of variations of emissivities of the load, thickness of the load and the residence time of billet in the furnaces were studied.