Patent ID: 7503952

Claim:
A filter element for removing material that is entrained in a gas stream, which comprises: a wall of a filtration medium which defines a hollow space, for a gas stream to flow from the space through the wall, and an end cap having an inlet tube extending into the hollow space for a gas stream to be supplied to the space, the inlet tube having a side wall extending between an upstream open end and a downstream open end, with at least one opening in its side wall, in which the inlet tube has an upstream band, a middlestream band and a downstream band, the said bands being axially adjacent to one another and non-overlapping, having equal axial lengths of at least 5% of the length of the inlet tube, and being arranged such their planes are perpendicular to the axis of the inlet tube, and in which the proportion of the area of the side wall that is open in the upstream band is smaller than that in the middlestream band, and the proportion of the area of the side wall that is open in the middlestream band is smaller than that in the downstream band.