Liquid Filling Measuring System with Variable Flow

This paper describes a system that is developed to solve a problem related to the packaging of chemical liquids. The problem arises in small chemical production plants where container packaging is done slowly, manually and with free-flowing methods. The user is selecting the chemical liquid type and the weight of the container. In a computer there is a database with the viscosity of each liquid. The most crucial parameter for the system to compute is the liquid flow. To achieve this, before the first container filling, the microcontroller receives from the computer the liquid's viscosity. Then, for each next filling, the microcontroller needs to measure the pressure at the filling tank outlet, calculates the filling time and controls the valve. During the filling process, weight is measured continuously and the filling duration is corrected. The advantage with this system is the quick filling of the containers, without user intervention, intermediate pauses and without the need to maintain the liquid in the initial tank at constant height.