Automation has been gaining interest in every branch today. The reason for the popularity of automation in industries today is due to its capability to reduce labour cost, reduce material wastage, increase the production quantity, to improve the quality of the product and to reduce idle time in manufacturing industry. In this work, an industrial process of glass molding and filling operation is simulated using the Fiddle PLC simulator. GRAFCET based modelling of discrete event is used in developing the PLC ladder logic program for the industrial process. The proposed method reduces labour cost by 40%, Increases production value by 55%, and reduces material wastage by 20% compared to manual operation. The proposed GRAFCET based model was found to be reliable, efficient, and accurate in performing the control sequence of the glass molding and filling operation. In future, it is proposed to develop the HMI (human machine interface) and the corresponding hardware will be developed for the same application.