Model Test Of The Flow Of Glass In A Closed Tube And Of Gob Formation By The Plunger (In German)

Model tests and calculations have shown that the Hagen-Poiseuille law is applicable to tubular feeders with indirect electric heating from all sides. Thus the diameter and length of the tube as well as the glass level can be states for the throughput required at given glass characteristics. Tests with a non-rotating plunger have shown that the glass must be made homogenous in the gob by a rotating plunger, rotating tube tube or stirrer because otherwise the glass will flow on the tube side of the plunger. In this case the glass will not be homogenous from a thermal and perhaps chemical point of view and so will not be satisfactory for forming in high output automatic machines.