| 摘要 |
A flow block and bushing assembly employing an orifice plate having a perforated drawing area with a planar undersurface against which bulk gas flow is directed for cooling and fiber attenuation purposes. The flow block is comprised of an interior layer of highly glass corrosion resistant material, such as zircon, and an exterior layer of highly thermal shock-resistant material. A flow passage extends through both of said layers and is lined with platinum foil. The bushing assembly is removably secured beneath the flow block and comprises a body of refractory material having a flow chamber extending therethrough in alignment with the flow passage. The flow chamber is lined with a platinum foil lining and the orifice plate is joined to the lining and extends over the lower end of the chamber. The orifice plate is reinforced by ribs integrally joined to and extending across the upper surface of its perforated drawing area and a perforated reinforcing plate is integrally joined to the ribs in spaced parallel relationship to the orifice plate. Electrodes are joined to the orifice plate to either side of the drawing area whereby electrical current may be passed through the orifice and reinforcing plates and flow chamber walls to effect the resistance heating thereof. Bulk gas flow is provided by a nozzle having a plurality of individual inlet conduits communicating with a common elongate discharge passage. An adjustable manifold communicates with the inlet conduits of the nozzle to provide for the selective supply of gas thereto and the nozzle is adjustably mounted so that its angular orientation relative to the undersurface of the drawing area may be varied. |
