Proposta de tecnologia para controle de velocidade de PIGs instrumentados utilizando lógica Fuzzy

Abstract

The speed control of smart PIGs is necessary, in oil and gas industry, for allow a better and safer pipeline inspection. This is possible when those smart it PIGs maintain a low speed while performs a pipeline inspection, in the search for defects as corrosion, cracks and dents. Our objective propose a technology for speed control of smart pigs using a by-pass valve triggered by a solenoid. This valve is able to control the pressure differential applied in PIG’s body. Once we control the pressure differential, it is possible to control the speed of this PIG. A experimental benchmark was mounted in reduced scale for simulation of the PIG speed excursion situation and acceleration suffered by the PIGs. The experimental benchmark allowed to studying the reactions of the upstream and downstream pressure over the by-pass valve.The Fuzzy logic was used for determine the opening and closing period this valve to control pressure differential. The experimental tests show substantial reduction in pressure differential value over PIG after happening speed excursion. Also, the time necessary for the pressure differential go to maximum and returns to default reference value. The results obtained allow conclude which is possible to controlling pressure differential applied in PIG, thus also the speed, using Fuzzy logic, acting opening and closing period of proposed by-pass valve.