| 摘要 |
<p>PURPOSE:To provide a burner for synthesis of silica fine particles for synthesizing a large-sized silica porous preform at high synthetic rate and to improve the yield of the preform synthesis by preventing crack and release of the side part of the silica porous preform. CONSTITUTION:The objective burner for synthesis of silica fine particles with a multiple flame from plural pairs of inflammable and self-combusting gases is characterized by satisfying the condition expressed by the formula IK+1-OK> IDK+1-ODK, wherein, among plural nozzles for flame-forming consisting of a pair of nozzles for feeding combustible gases, that for feeding inert gases and that for feeding self-combusting gases existing at the Lth flame from the inside of the multiple flame, the outside diameter of the Kth pipe is defined as OK and the inner diameter of the (K+1)th pipe on the outside of the Kth pipe is defined as IK+1, and among plural nozzles for the (L+1)th flame existing on the outside of the Lth flame, the outside diameter of the Kth pipe is defined as ODK and the inside diameter f the (K+1)th pipe on the outside of the Kth pipe is defined as IDK+1.</p> |
