Abstract: Microwave radiation of frequency 0.1 to 20 GHz, is applied to the melt of viscosity in the range 104 to 101 Pa·s. The outside surface of heated space, where an outlet of the waveguide of microwave radiation is located, can be cooled. The microwave radiation in the melt may be reflected by the reflective metallic elements in the melt back to the place of radiation entry into the melt and shielded from the surroundings by a shielding metallic element. An outlet is provided of at least one waveguide from the source of the microwave radiation, in any direction to the outside surface of the melt, into the space with the melt of a given viscosity. At least one waveguide is led, for example, to the outside surface of the bottom of the channel of the forehearth.

Abstract: Microwave radiation of frequency 0.1 to 20 GHz, is applied to the melt of viscosity in the range 104 to 101 Pa.s. The outside surface of heated space, where an outlet of the waveguide of microwave radiation is located, can be cooled. The microwave radiation in the melt may be reflected by the reflective metallic elements in the melt back to the place of radiation entry into the melt and shielded from the surroundings by a shielding metallic element. An outlet is provided of at least one waveguide from the source of the microwave radiation, in any direction to the outside surface of the melt, into the space with the melt of a given viscosity. At least one waveguide is led, for example, to the outside surface of the bottom of the channel of the forehearth.

Abstract: In apparatus for the straight-line shearing of molten glass gobs, first and second carriage members have mounted thereon one or more opposing pairs of shear blades which are caused reciprocally to move towards each other and then away from each other along a substantially straight line between an open position and a closed cutting position. The carriage members are slidably mounted on wayrods and are connected to diametrically opposed crank arms extending from a rotatably driven shaft. As the shaft is caused to rotate, the carriage members reciprocally slide on the wayrods between the open and closed positions.

Abstract: Forehearths for use in glass production comprise a refractory trough (52) for molten glass with an insulating roof thereover, means for heating glass in the trough and means for blowing cooling air across the inside of the roof surface; the forehearth being constructed of at least two sections (A, B and C) which have different insulating characteristics from each other. Preferably the forehearth roof is made up of prefabricated block members of refractory material lying side by side and each of which member spans across the trough. Different insulation is provided over the prefabricated block members to provide different insulating characteristics within sections of the forehearth. The invention also provides prefabricated members for use in the construction of the forehearth according to the present invention.

Abstract: In glass gob forming apparatus which includes one or more reciprocatable plungers each mounted above a respective orifice in the floor of a refractory trough such that on axial reciprocation of the plungers in use molten glass is forced in the form of gobs through the orifice, the plungers being surrounded by a refractory cylinder, there is provided a refractory heat insulating body within the cylinder around the plungers.