The cleaning and storage of abandoned pipelines are an effective way to prevent potential dangers and environmental pollution. In this paper, an abandonment of one crude oil pipeline by using pigging ball pushed by nitrogen in China is set as an example, by establishing a physical and mathematical model of the pigging ball pushed by nitrogen, the process calculation of nitrogen sweeping is done, the operating procedures and implementation steps of the nitrogen sweeping technology are introduced in detail. All this may provide some technical references for the similar engineering practice in future.