Optimisation of sandblasting and brushing on the line for acid-free cleaning of sheet metal

Pred hladnim valjanjem je treba s površine pločevine odstraniti železov oksid. Splošno uveljavljen tehnološki postopek je luženje s kislino, v tem primeru pa železov oksid odstranjujejo mehansko. Pločevino peskajo in krtačijo, pri tem sta pomembni očiščenost in hrapavost površine. Namen diplomske naloge je ugotoviti povezavo med parametri obdelave na liniji in hrapavostjo površine. Na kakovost končnega izdelka vpliva mnogo dejavnikov, ki so v delu podrobno predstavljeni. Vplive na pločevino smo ugotavljali z meritvami površinske hrapavosti, ki mora biti nizka. Glavna cilja, ki nam ju je uspelo doseči, sta povečanje produktivnosti in zmanjšanje obrabe brusnih krtač. Dokazali smo, da bi lahko ob spremembi parametrov na liniji maksimalno hitrost pomikanja traku povečali za 2 m/min. Hrapavost je bila namreč pred spremembo in po njej zelo podobna. Ugotavljamo, da še obstajajo možnosti za nadaljnje izboljšave.Before cold rolling it is necessary to remove iron oxide from the sheet metal. A commonly used technological procedure is pickling with acid, but here it is done mechanically. Sheet metal is sandblasted and brushed. It is important that surface is well cleaned and has low roughness. The purpose of the thesis is to find out the dependence between processing parameters on the line and surface roughness of steel strip. There are many factors that have influence on the quality of finished product and they are presented in detail. Impacts on sheet metal were determined by measurements of surface roughness, which should be low. Two main goals, which were achieved, are increased productivity and reduction of the wear of abrasive brushes. We proved that it is possible to increase maximum speed of steel strip by 2 m/min if some parameters on the line are changed. The roughness was similar before and after the change. There are many other opportunities for further improvements