Abstract: A mechanical process for filling the tubes (3) of tubular reactors with granular solids, e.g. catalysts, wherein two or more streams of material, e.g. of different catalytic activity, can be introduced in a controlled manner into each tube (3) which is to be filled, from two or more stock vessels (1,2) via two or more dispensing devices (MI, MZ) mounted above the upper tube end plate (13). By this process, different thermal/catalytic reaction profiles can be achieved over the length of the tube, or in certain groups of tubes within the tubular reactor, with substantially less time being required for filling the tubes (3).