Design, Construction and Experimental Analysis of Free Floating Pig for Pipeline Leak Detection

This thesis focuses on the development of a free floating tool called Pig Tool, which is capable of detecting and locating oil and gas pipeline leakages using differential pressure detection method. Leakages can result in significant environmental and financial consequences due to pipeline corrosion during construction, operation and decommission. To ensure its integrity, periodical inspection is vital to assess the significance of pipeline defects. Traditional detection equipment or pig has a risk of blocking a pipeline. This study aims to design free swimming inspection device which can run freely in a pipeline with minimum risk of blocking a pipeline, and to develop a sensitive leak detection system that can detect and locate leaks in oil and gas pipelines. Leakage of pressurized product from a pipe creates a pressure differential across the pipe wall, and this pressure drop can be identified by using a pressure sensor, on board the Pig Tool. Pressure sensor, manufactured by DFRobot is used as the leak detection equipment for identifying leaks in pipeline. The Pig Tool was designed and fabricated in spherical shape and the sensor is programmed using Arduino Integrated Development Environment to the microprocessor, Arduino UNO R3, to allow the sensor to detect the pressure and temperature difference. The product was tested in a pipeline to test the mobility of the Pig Tool, and to validate the functionality of the sensor. Three indirect tests were performed such as Leak test, Sensor test and Pig Tool test due to the unavailability of pipeline facilities for test loop. The experimental results show that Pig Tool is fully sealed, leak proof and has the mobility to navigate inside pipe. Consequently, changes in temperature and pressure of surrounding were continuously detected by the on board sensor. The data obtained from the sensor was successfully processed by the microprocessor and stored in the memory storage using Micro SD Shield. Future development of the Pig Tool with the incorporation of pressure sensor is required to detect differential temperature and pressure to facilitate actual test run using a scaled pipeline.