Scraping apparatus for the paper industry, of the type which consists of a scraping blade (l), a support (s) for the scraping blade (l) with a pivot swivel pin (e) with respect to a tray (4), said tray being supported (4) on the frame (b) of the apparatus, characterized because magnetic means are used to exert magnetic forces between the tray (4) or from the fixed element to it and the frame (b), and there are means of action on said magnetic means to activate/deactivate the magnetic forces between the tray (4) and the frame (b).The magnetic means consist of at least one zone (z) of ferromagnetic material and several permanent magnets or electromagnets (1) placed on the tray (4)-frame (b) in a conjugate/corresponding manner.