Abstract: A method for delivering a glass stream having a first inner layer and a second outer layer, including a generally vertical orifice, and delivering glass from a second source such that the glass from the second source provides an outer layer about the glass from the first source as it flows through the orifice. A resistance heated tube assembly is made of platinum or material having similar resistance heating properties and extends from a glass source to an orifice through which the glass flows from a glass source for the inner layer. The tube assembly includes a tube portion having an inlet end that communicates with the source for the outer layer and an outlet end that communicates with the source. The tube portion has an axis positioned at any angle ranging between the horizontal and vertical but preferably has an axis which is more vertical than horizontal. Flanges are secured to the ends of the tube portion, and the flanges are connected to an electric power supply.

Abstract: Apparatus for forming a cased glass stream having an inner core glass surrounded by an outer casing glass includes a spout for receiving core glass from a first source and delivering such glass through a first orifice. A second orifice is vertically spaced beneath and aligned with the first orifice, and is surrounded by an annular chamber that communicates with the second orifice through the gap between the first and second orifices. A tube delivers casing glass from a second source to the annular chamber in such a way that glass flows by gravity from the first and second sources through the orifices to form the cased glass stream. The core glass delivery spout includes a reservoir for receiving and holding the core glass, and having at least one lower opening of a first diameter. An orifice ring is positioned beneath the reservoir, and has at least one opening of second diameter less than the first diameter aligned with the first opening and forming the first orifice.

Abstract: A multiple glass feed system for use with a glass forehearth including a plurality of closely spaced plungers, each of which is individually adjusted independently of the other. The upper end of each plunger is oval in cross section and the lower end is round. The oval portions of the plungers are each supported in an individual clamping mechanism having a chuck housing, a curved liner plate within the housing, and a cap screw which extends between the housing and liner plate to engage the upper end of the plunges and clamp the plunger in the housing to arrange the plungers in side by side relation to each other with the long axis of each oval portion parallel to the long axis of the adjacent plungers.

Abstract: A multiple glass feed system for use with a glass forehearth including a plurality of closely spaced plungers, each of which is individually adjusted independently of the other. The upper end of each plunger is oval in cross section and the lower end is round. The oval portions of the plungers are provided in side by side relation with the long axis of each oval portion parallel to the long axis of the adjacent plungers.