Footwear
| Thu 17 Oct 2024
Beijing, Oct. 17 -- State Intellectual Property Office of China has awarded CNPC Bohai Drilling Eng and China Nat Petroleum a patent for easily-drilled anti-erosion float collar float shoe. Jiang Benqiang, Ji Xiaona, Song Jianming, Yang Chao, Cheng Qi, Liu Yibin, Ye Weijuan, Jiang Likun, Zhou Hao, Zhang Jinghua, Wang Zhigang, Go..