Oil & Gas
| Tue 17 Mar 2026
Beijing, March 18 -- Daqing Oilfield and PetroChina have applied Chinese patent for Combination Tool for Maintaining Pumping Unit Wellhead Packing Box. Zhu Guanghai, Jiang Xiaodong, Ma Jingxuan, Jiang Junyu, Wang Huizhe, Zhang Heng, Cao Tengfei, Dong Jian, Liu Hui, Lou Yingbo, Wang Jian, Xin Longhai, Sun Mengyang and Liu Yu deve..