Tianjin Yiyong Changsheng Engineering Co., Ltd. mainly conducts pipeline pressure testing and ball passing according to market demand. Strength testing is mainly used for high-pressure pressure vessels and PetroChina oil and gas pipelines. In the 14 years from 2005 to 2019, our company has independently completed the 20km gas transmission project of Tianjin Jinghai DN400 pipeline, the 6km DN600 high-pressure pipeline in Tianjin Xianshuigu Beiyang Garden, the 40km DN700 high-pressure pipeline in Tianjin Outer Ring, the 33km DN700 high-pressure pipeline project in North Ring, the 22km DN700 high-pressure pipeline in Qinghe Farm, the 20km Jitang high-pressure DN700 high-pressure pipeline, the 56km high-pressure pipeline in Tianjin Avenue, and other projects of Tianjin Municipal Government. In 2007, we introduced two imported Atlas high-pressure air compressors to support the airtight test according to the market demand. We have formed an integrated acceptance construction for the strength test, cleaning test (ball passing), and airtightness test of high-pressure oil and gas pipelines. In the same year, we participated in the construction of the Jibao Line (Baojing Phase 1 36km), and since then, we have participated in the pressure testing construction of the Baojing Phase 1 36km, Baojing Phase 2 56km (DN1000) power plant branch line 10Km, completed the overall airtightness construction of the Baojing Line 100km, the ball passing and airtightness construction of the Jitang High Voltage Line 20km, and the ball passing airtightness construction of the 112 Line 26km. We have received unanimous praise from the owners, management units, and municipal government.