FIGURE 5.-Process of forming a bottle. at d, e, f, and g) form the bottle. tions a, b, and c. d f g In the Owens machine the mold is filled by suction and two successive "blow" operations (similar to those shown In a competitive method, called the gob-fed process, glass is dropped into the molds in gobs, as shown in opera PLUG FIGURE 6.-Diagram of operation of feeder, which delivers gobs of glass from the tank to the molds of the forming machine, in the gob-fed process. For NARROW-NECK containers the so-called BLOW AND BLOW process generally is employed (See Fig. 5) in which compressed air is used in each of the blowing operations. For machines used to make WIDE-MOUTH Ware (Miller) the socalled PRESS AND BLOW method generally is employed (Fig. 11). In this process the first blowing operation is supplanted by a "pressing" operation in which a plunger is used to form the cavity in the parison (Fig. 12). Many articles, such as tumblers and dishes, are made by a PRESSING operation alone (Hartford and Miller). This method uses a plunger to perform the entire operation of forming (Fig. 13). The completed bottles are carried by the conveyor into a LEHR or oven (Fig. 14), where they are STACKED, or arranged in closely spaced rows, on a belt which moves slowly through a long chamber or tunnel. The temperature of the bottle is lowered slowly in this oven so that internal strains in the bottle are relieved. This process of ANNEALING tends to prevent the finished product from cracking or breaking when subjected to sudden jars or rapid changes in temperature. |