Filtering cartridge, in particular for internal combustion engine

Filter cartridge comprising a tubular filter element extending along a central axis between two longitudinal ends, said filter element having an external cylindrical surface and an internal cylindrical surface forming a central passage for fluid, said filter element being made from a porous, flexible sheet forming a succession of pleats with axial ridges, these pleats forming vanes all curved in a same angular direction, each vane comprising first and second portions each having a concave face and a convex face, each of said first and second portions of each vane extending between an inner end close to the internal cylindrical surface of the filter cartridge and an outer end close to the external cylindrical surface of the filter cartridge, the concave face of the first portion of each vane communicating with the central passage and the convex face of the second portion of each vane communicating with said central passage, the first and second portions of each vane being joined at their outer ends, the second portion of each vane being joined to the first portion of an adjacent vane at their inner ends, and the porous sheet having separator elements which keep the first and second portions of the vanes spaced apart from one another and which stiffen said porous sheet, wherein the first and second portions of each vane have hinge lines which are not stiffened by the separator elements and which extend parallel with the central axis of the filter element between the two longitudinal ends of said filter element, said hinge lines sub-dividing each first and second portion into at least three panels each having separator elements, and the adjacent panels of each vane which are joined to one another by one of said hinge lines form angles ranging between 110 and 175 degrees.