Glass production

Glass production involves two main methods – the float glass process that produces sheet glass, and glassblowing that produces bottles and other containers. It has been done in a variety of ways during the history of glass. Broadly, modern glass container factories are three-part operations: the "batch house", the "hot end", and the "cold end". The batch house handles the raw materials; the hot end handles the manufacture proper—the forehearth, forming machines, and annealing ovens; and the cold end handles the product-inspection and packaging equipment. Batch processing is one of the initial steps of the glass-making process. The batch house simply houses the raw materials in large silos (fed by truck or railcar), and holds anywhere from 1–5 days of material. Some batch systems include material processing such as raw material screening/sieve, drying, or pre-heating (i.e. cullet). Whether automated or manual, the batch house measures, assembles, mixes, and delivers the glass raw material recipe (batch) via an array of chutes, conveyors, and scales to the furnace. The batch enters the furnace at the "dog house" or "batch charger". Different glass types, colours, desired quality, raw material purity/availability, and furnace design will affect the batch recipe. The hot end of a glassworks is where the molten glass is manufactured into glass products. The batch enters the furnace, then passes to the forming process, internal treatment, and annealing. The following table lists common viscosity fixpoints, applicable to large-scale glass production and experimental glass melting in the laboratory: The batch is fed into the furnace at a slow, controlled rate by the batch processing system. The furnaces are natural gas- or fuel oil-fired, and operate at temperatures up to . The temperature is limited only by the quality of the furnace’s superstructure material and by the glass composition. Types of furnaces used in container glass making include "end-port" (end-fired), "side-port", and "oxy-fuel".