The Uni-directional Scraper Pig is a commonly used pig consisting of four cups and a steel frame. This pig is designed to effectively remove soft dirt and dust from pipelines. Its leather cups serve two important functions. Firstly, they provide excellent sealing performance, ensuring complete separation of liquids or gases at both ends of the pig. This creates a pressure difference that propels the pig forward. Secondly, the leather cups are capable of cleaning debris and dirt from the inner walls of the pipe.