Workers of the No.1 gas collection station of the Qinghai Oilfield work in Haixi Mongolian and Tibetan Autonomous Prefecture, northwest China's Qinghai Province, Jan. 6, 2021. Workers stick to their posts in spite of the severe cold in Qinghai Oilfield. (Xinhua/Zhang Manyi)

Liu Liwei, monitor of the No.1 gas collection station of the Qinghai Oilfield, works in Haixi Mongolian and Tibetan Autonomous Prefecture, northwest China's Qinghai Province, Jan. 6, 2021. Workers stick to their posts in spite of the severe cold in Qinghai Oilfield. (Xinhua/Wang Bo)

Workers work at Shizigou operating platform in Qinghai Oilfield, Qaidam Basin, northwest China's Qinghai Province, Jan. 7, 2021. Workers stick to their posts in spite of the severe cold in Qinghai Oilfield. (Xinhua/Lan Xiang)

Workers work at Shizigou operating platform in Qinghai Oilfield, Qaidam Basin, northwest China's Qinghai Province, Jan. 7, 2021. Workers stick to their posts in spite of the severe cold in Qinghai Oilfield. (Xinhua/Wang Bo)

Jia Hualong, deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Jan. 7, 2021. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Jia Hualong (C), deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Dec. 28, 2020. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Jia Hualong, deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Dec. 28, 2020. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Jia Hualong, deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Dec. 28, 2020. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Photo taken on Jan. 7, 2021 shows Jia Hualong, deputy leader of the No. 1205 drilling team at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Jia Hualong, deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Dec. 28, 2020. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)

Jia Hualong, deputy leader of the No. 1205 drilling team works at the oil platform in Daqing Oilfield in Daqing, northeast China's Heilongjiang Province, Dec. 28, 2020. Jia Hualong, born in 1989, is the deputy leader of the No. 1205 drilling team in Daqing Oilfield. Jia assists other workers with drilling even though the temperature drops to minus 30 degrees Celsius during winter around here. The spirit of "iron man" was born from Wang Jinxi, a model worker of the oilfield who devoted his life to the development of the petroleum industry. Nowadays, faced with COVID-19 pandemic and severe cold, Jia has carried on the spirit to dedicate himself to his motherland. (Xinhua/Wang Song)