In low-pressure casting, the liquid aluminum is pressed from below into the rim mold - the rim's casting mold - using a riser pipe. The molten aluminum is pressed into the mold cavity by means of gas pressure. During the transition to the solid state, the gas pressure is maintained in order to compensate for the volume that decreases as a result of cooling with the melt flowing in (feeding), which guarantees optimal material density. The desired solidification is from top to bottom, which is already taken into account in the design of the rim, e.g. through favorable cross-sectional gradations. All cast rim blanks are then checked fully automatically in X-ray systems before they are further heat-treated and tempered if necessary.