<p>In the oil and gas industry, pipeline transportation is crucial for ensuring energy supply. However, problems such as internal deposits and corrosion in pipelines can undermine their safe, efficient, and stable operation. Pipeline pigging technology is essential for maintaining pipelines, but existing pigging technology faces challenges in dealing with complex deposition situations and ensuring cleaning effects while minimizing pipeline damage. To address these issues, this study comprehensively reviews pipeline pigging technology. It combines experimental research and numerical simulation methods. Through a series of experiments on bypass pigs under different pipeline environments and working conditions, key factors like bypass fraction, flow rate, and pressure that affect the pigging process were identified. The construction of various mathematical models for numerical simulation further explored the impacts of factors such as bypass diameter, fluid properties, and pipeline geometry on the flow behavior, cleaning efficiency, and dynamic speed of the pig. This paper offers a comprehensive resource for the design, selection, and optimization of pipeline pigs. It also advances the development of pipeline pigging technology, which is of great significance for ensuring the safe and efficient operation of oil and gas pipelines.</p>