| Summary: | Detta examensarbete handlar om forpackning av keramiska substrat. Canning ar det universella namnet pa forpackning av keramiska substrat. Keramiska substrat kan vara katalysatorer eller partikelfilter som anvands som ett efterbehandlingssystem i bensin och Diesel applikationer. Examensarbetet genomfordes hos Scania CV AB. I installationsprocessen sveps en keramisk fibermatta runt det keramiska substratet. Substratet inkapslas sedan med ett metalholje. Rapporten inleds med att beskriva olika installationsmetoder. Fordelar och tillampningsomraden for det olika metoderna beskrivs. Sedan beskrivs det ingaende komponenterna. Support mattor, katalysatorer, partikelfilter, wiremesh stod och metaller diskuteras. Metoden for att berakna vilket mattryck som behovs for att halla kvar substraten beskrivs. Metoder for att berakna accelerationskrafter och tryckfallskrafter beskrivs. Sedan diskuteras temperaturmatningar. Till sist beskrivs hur designprogrammet fungerar och hur det anvands. Det storsta problemet vid installationen ar de daliga tillverkningstoleranserna hos de ingaende komponenterna. De uppmatta temperaturerna var hoga sa varmeutvidgning kan leda till att substraten lossnar. Hoga tryck vid installationen kan leda till att substraten spricker vid for laga tryck kan substraten lossna i drift. === This thesis treats canning of ceramic substrates. Canning is the packaging of ceramic catalysts and particulate filters which are used as an aftertreatment system for Gasoline and Diesel engines. The thesis was conducted at Scania CV AB. In the canning process a ceramic fiber mat is first sleeved around the ceramic substrate. The substrate and mat are then canned in a metal housing. The thesis starts of with describing different canning methods. Advantages and application of the methods is described. Then the different components in the canning system are described. Different support mats, catalysts, particulate filters, wiremesh and steels for the housing are discussed. The method for calculating which mat pressure is needed is described. How to calculate holding forces from backpressure and acceleration are described. Temperature measurements are discussed. How the design program works and how to use the program is then discussed. The major problem in canning is poor manufacturing tolerances of the components. Thermal expansion will influence the robustness of the system. The measured temperatures were high due to the filter and catalyst being enclosed inside the muffler. This combined could lead to substrate slippage. The tolerances could mean that high pressure occur during caning that could lead to substrate cracking during canning.
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