a continuously operating press for the production of particle boards , fiber boards and similar wood boards and plastic boards comprises the combination of the following features : a ) the press beams comprise individual beams of different lengths which can be connected to one another and are made up of web plates and ribs connecting the latter , the upper individual modules being suspended on two i - section girders which represent the length of the press and which take the pretensioning forces of the steel belts , while the lower press beam rests on two i - section girders anchored in the foundation ; b ) the two press beams are connected positively by tiebars that can be pivoted out and / or replaced quickly ; and c ) the cylinder - piston arrangements of one row are arranged between the tiebars and the heating platens together with their supporting crossmembers and supporting bodies or supporting strips in such a way that they can be introduced into and removed from the pressing zone after the release of some of the tiebars .