| 摘要 |
<p>A filter element, adapted to be precoated with a filter aid, includes a porous tubular core 82, and a means supporting the filter aid precoat including a discontinuously slotted sheet 86 arranged concentrically about the tubular core 82. Each of the slots 88 has an elongate configuration, and provides an absolute particle retention ability of less than 30 microns while decreasing the bubble point pressure over apparatus of the prior art, thereby reducing gas entrapment in the filter element. In alternative embodiments 1 the means for supporting the filter aid precoat is a conventional mesh which extends only up to the edge of vent sleeve 90 and the discontinuously slotted sheet, in the form of a sleeve or separate discs, is confined to inside sleeve 90 to cover vent apertures 92. <IMAGE></p> |
