Control Problems of Rotary Glass-Working Machinery

The glass industry prefers mechanical or hydraulic control systems over electrical control systems. This choice is often based on previous experiences where electrical controls have shown low reliability and high maintenance cost when exposed to the heat, light, dirt, sand, broken glass, and rapid temperature shifts found in glass plants. The special problems of rotating glass machines are presented. Such machines are indexing, continuous rotation, lathe type, conveyor chain driven, etc. In rotary machines glass is cut, pressed into shapes, sealed to other glasses, sealed to metal, it is exhausted to achieve a vacuum or a special gas atmosphere is created. Into these machines go electric motors, actuators, valves, transformers, relays, switches, and transducers.