Abstract: A fuel pre-filtering element may comprise a casing provided with a fuel outlet, an internal tube, an upper annular element, a lower annular element, a filtering element and a cover. The filtering element may be arranged around the internal tube The upper and lower annular elements may be respectively fixed to the upper and lower ends of the filtering element The filtering element may be arranged inside the casing such that the internal tube establishes a contact with the fuel outlet, the upper annular element is arranged around the fuel outlet and in contact with an upper surface of the casing, and the upper annular element is deformed and forms an annular projection. The annular projection may establish a seal between the internal tube, the fuel outlet and the casing. The arrangement of the filtering element may be inside the casing and further form a region of unfiltered fuel.

Abstract: A filter device may include a filter housing cup, a filter head, and a ring filter element arranged in the filter housing cup. The ring filter element may include an upper end plate on which at least two radially outward projecting bayonet wings are arranged which interact with a plurality of recesses disposed in the filter housing cup. The plurality of recesses may respectively define an undercut contour and a first end position of an associated bayonet wing guided therein. At least two driving elements may be arranged on the upper end plate. At least two ramps and two stops may be arranged on the filter head such that, when fitting the filter device, the at least two driving elements slide on the at least two ramps to the two stops and press the at least two bayonet wings into the undercut contour of an associated recess.

Abstract: A filter device may include a filter housing cup, a filter head, and a ring filter element arranged in the filter housing cup. The ring filter element may include an upper end plate on which at least two radially outward projecting bayonet wings are arranged which interact with a plurality of recesses disposed in the filter housing cup. The plurality of recesses may respectively define an undercut contour and a first end position of an associated bayonet wing guided therein. At least two driving elements may be arranged on the upper end plate. At least two ramps and two stops may be arranged on the filter head such that, when fitting the filter device, the at least two driving elements slide on the at least two ramps to the two stops and press the at least two bayonet wings into the undercut contour of an associated recess.

Abstract: A fuel pre-filtering element may comprise a casing provided with a fuel outlet, an internal tube, an upper annular element, a lower annular element, a filtering element and a cover. The filtering element may be arranged around the internal tube The upper and lower annular elements may be respectively fixed to the upper and lower ends of the filtering element The filtering element may be arranged inside the casing such that the internal tube establishes a contact with the fuel outlet, the upper annular element is arranged around the fuel outlet and in contact with an upper surface of the casing, and the upper annular element is deformed and forms an annular projection. The annular projection may establish a seal between the internal tube, the fuel outlet and the casing. The arrangement of the filtering element may be inside the casing and further form a region of unfiltered fuel.

Abstract: A diesel fuel pre-filtering system may include a structure for housing at least two filtering areas, a fuel inlet area, and a fuel outlet area. The system may also include an inspection window including a drain for water, a first filtering area structured to define a restriction connecting between the fuel inlet area and a subsequent filtering area, and a second filtering area structured to define a restriction connecting between a preceding filtering area and the fuel outlet area. The structure and the inspection window may be composed of a thermoplastic material distinct from each other and connected to each other via a permanent bond.