ORIFICE PLATE FOR USE IN BUSHING FOR SPINNING GLASS FIBERS

摘要

An orifice plate for use in a bushing for spinning glass fibers having a number of orifices closely spaced as to cause joining of molten glass cones formed at the outlet of adjacent orifices if cooling air is not blown against the lower surface of the orifice plate, each orifice consisting of an upper cylindrical bore section opening in the upper surface of the orifice plate and a lower cylindrical bore section extending coaxially with the upper bore section to open in the lower surface of the orifice plate and having a smaller diameter than the upper bore section, in which with regard to diameters and axial lengths of the upper and lower bore sections a special dimensional relationship is provided between orifices disposed along the outermost periphery of the orifice area and remaining orifices disposed at the inner side of the outermost orifices so as to ensure even frictional resistance to molten glass passing through all orifices irrespectively of the difference of heat radiation between the outermost and the inner orifices.