This thesis has been done at the powder department (GH) at AB Sandvik Coromant in Gimo. With a rheometer measurements has been made on raw materials and powder blends. The focus of this report has been to find correlations between raw material powders and press data, comparisons have also been made between raw materials and powder blends.The rheometer can show information of how a powder act in flow conditions, together with air and with pressure. Analyses has been done comparing the rheometer data with press parameters (for example: rejected orders, weight variations and the compaction pressure) with the goal to find correlations between the powders flow properties and the powders compaction in production.The measurements and analyses have been showing that the powder flow properties depends on the powders composition and that properties like flow rate, aeration and permeability varies between powder blends and batches of the same powder sort. It seems to exist a correlation between the pressure force and the flow rate of a raw material.

Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity. Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.