ORIFICE PLATES FOR GLASS FIBER DRAWING BUSHING

摘要

An orifice plate for a glass fiber drawing bushing having a flat undersurface and a number of orifices formed through the orifice plate, in which longitudinal and transverse parallel grooves are formed on the undersurface of the orifice plate in such a way that the undersurface is divided by the longitudinal and transverse grooves into a number of square sections within each of which is located one of orifices. In this way the orifice plate is deformed just as having tip nozzles in a shape of quadrangular prism and therefore the pitch of orifices arranged in the orifice plate may be made as small as in conventional tip nozzles. When the grooves are formed in the undersurface of a closely spaced orifice plate which requires to blow cooling air against the undersurface of the orifice plate so as to prevent flooding of the undersurface by molten glass and ensure stable glass fiber drawing operation, the orifice plate may be used for drawing finer glass fibers which cannot be drawn with conventional closely spaced orifice plates without grooves.