What oil companies are there in Xi 'an?

China Petroleum Changqing Oilfield Company Headquarters, Yanchang Petroleum Group, Xi 'an Petrochemical Company of China Petrochemical Company. All in the northern suburb of Xi 'an. Oil exploitation is all in the loess plateau of northern Shaanxi. Changqing Petrochemical is in Xianyang, which is very close to Xi. The three expanded refineries are in Yan 'an, Yulin and Yongping respectively. PetroChina logging is also in Xi 'an. Northwest Petroleum Pipeline Bureau is in the northern suburb of Xi 'an. Changqing part of Qing Chuan Drilling is located in the northern suburb of Xi.