Abstract: An arrangement for processing ligno-cellulose containing particles for the manufacture of wood-product plates. These have layers of oriented chips, and a chipper comminutes raw material. The fine material and dust are separated by a sifting device, and the sifted chips are provided with binder material by a gluing device. The chipper produces more chips of as great a length as possible than are required for forming of at least one cover layer of a mat. Behind the chipper, there are provided a wet-chip bunker and a dryer. The sifter separates the chips, obtained after removal of the fine material and the dust, into two fractions. The chip composition of one of these fractions, during the processing time, constantly contains chips which are as long as possible and which are more than that required for forming the mat layer. The other fraction has shorter chips obtained during chipping, and both fractions are present each in at least one bunker.