Homogenising valve with axial symmetry, particularly for application to fibrous fluids, comprising: a valve body defining a through hole having axial development with respect to the valve body; a first piston housed in said through hole; a second piston housed in said through hole and integrally coupled to said first piston; an inlet for fluid at high pressure; an outlet for homogenised fluid at low pressure; a first annular chamber afforded between said valve body and said first piston, said inlet gripping said first annular chamber to transfer to it the fluid at high pressure; a second annular chamber afforded between said valve body and said second piston, said outlet gripping said second chamber to receive from it the fluid at low pressure; an annular passage head interposed between said first chamber and said second chamber, an annular striking head integrally coupled to said first piston and to said second piston so as to form an assembled organ; means for moving said assembled organ in an axial direction towards the passage head so that said striking head defines with said passage head an interspace of passage of the fluid from said first chamber to said second chamber, characterised in that: said first piston presents a free end having a cogged profile suitable for engaging a cogged tool or apparatus so as to place said assembled organ in rotation, and in that the zone near said interspace of passage is reversible, i.e. the arrangement of the passage head and of the striking head can be inverted. a valve body defining a through hole having axial development with respect to the valve body; a first piston housed in said through hole; a second piston housed in said through hole and integrally coupled to said first piston; an inlet for fluid at high pressure; an outlet for homogenised fluid at low pressure; a first annular chamber afforded between said valve body and said first piston, said inlet gripping said first annular chamber to transfer to it the fluid at high pressure; a second annular chamber afforded between said valve body and said second piston, said outlet gripping said second chamber to receive from it the fluid at low pressure; an annular passage head interposed between said first chamber and said second chamber, an annular striking head integrally coupled to said first piston and to said second piston so as to form an assembled organ; means for moving said assembled organ in an axial direction towards the passage head so that said striking head defines with said passage head an interspace of passage of the fluid from said first chamber to said second chamber, characterised in that: said first piston presents a free end having a cogged profile suitable for engaging a cogged tool or apparatus so as to place said assembled organ in rotation, and in that the zone near said interspace of passage is reversible, i.e. the arrangement of the passage head and of the striking head can be inverted. said first piston presents a free end having a cogged profile suitable for engaging a cogged tool or apparatus so as to place said assembled organ in rotation, and in that the zone near said interspace of passage is reversible, i.e. the arrangement of the passage head and of the striking head can be inverted.