초록 ▼

There is disclosed a method of selectively plugging broken fibers included in a bundle of hollow fibers having open ends protruding from a tubesheet and closed ends distal from the tubesheet. The protruding open ends are immersed in a curable, fluid sealant and capillary attraction is utilized to dr

There is disclosed a method of selectively plugging broken fibers included in a bundle of hollow fibers having open ends protruding from a tubesheet and closed ends distal from the tubesheet. The protruding open ends are immersed in a curable, fluid sealant and capillary attraction is utilized to draw the sealant into the broken fibers. The resistance to compression of the gases in the unbroken fibers is such that the sealant does not move into the latter fibers so far that they will not be open after the protruding ends are removed. The imbibed sealant is cured in place and the protruding fiber ends are cut off flush with the final surface of the tubesheet. This method is of particular value in preparing tubesheet-fiber assemblies for use in high temperature alkali metal-sulfur battery cells, wherein the hollow fibers function as an electrolyte-separator.

대표청구항 ▼

The method of treating a tubesheet/hollow fiber assembly to ensure that any defective fibers included therein will be selectively plugged, said method comprising A. providing as said assembly one which comprises a bundle of hollow fiber lengths passing through and engaged with a rigid wall member or

The method of treating a tubesheet/hollow fiber assembly to ensure that any defective fibers included therein will be selectively plugged, said method comprising A. providing as said assembly one which comprises a bundle of hollow fiber lengths passing through and engaged with a rigid wall member or tubesheet having first and second generally parallel faces, all of said lengths having open ends protruding from said first face and at least a majority of said lengths having closed-ended portions extending from said second face, B. immersing said open fiber ends in a pool of a liquid sealant to a depth such that the distance between said first face and the surface of said pool external to the fiber ends is d, the force of capillary attraction between the walls of said fibers and said sealant being such that said sealant is drawn into said defective fibers for a distance greater than d, thereby filling them to a level beyond said face, the resistance to compression of the vapors within the closed ended lengths being such that said capillary attraction does not suffice to draw the sealant into said closed ended lengths beyond a point substantially below said level, C. removing the unimbibed sealant from contact with said protruding fiber ends, the imbibed sealant being so composed as to be convertible, in-situ and at a temperature below the distortion temperature of said lengths, to plugs of a solid, non-porous material sealingly bonded to the fiber walls and having a coefficient of expansion substantially matching that of the fiber material, D. converting the imbibed sealant to said plugs and E. severing the protruding fiber ends from said tubesheet, with the result that the defective fibers in the treated assembly are plugged and the good fibers are not plugged.