Computer Control of Glass Forming and Tempering

A digital computer controls the operation of a gas hearth process. The gas hearth is used to shape and temper glass templates for automotive applications. To produce a quality product, the computer regulates the temperatures and pressures throughout the lehr to obtain proper form and break pattern (i.e., temper) in the finished part. The computer also performs limit checking for the process variables, logs alarm messages, and prints lehr status reports for the operators and process engineers.