METHOD FOR MANUFACTURING POROUS GLASS BODY, AND POROUS GLASS BODY

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a high-quality porous glass body of uniform bulk density, and a porous glass body.SOLUTION: Three or more burners 13 for forming glass fine particles are each supplied with at least a flammable gas and a raw material gas of glass to form glass fine particles. A target glass rod 11 and the burners 13 are subject to relative reciprocating motion in the axial direction of the glass rod 11 while rotating the glass rod 11 around its axis. The turn-back point of the reciprocating motion is displaced with a constant length and the direction of displacement of the turn-back point is reversed after the turn-back point reached a predetermined position. The glass fine particles formed by the burners 13 are thus deposited on the glass rod 11 to manufacture a porous glass body G. Flame conditions of the burners 13 are changed so as to lower flame temperature near the turn-back point.