World’s largest steel maker Baowu announced that the high end sulfur-resistant gas sealing casing designed & developed by Baosteel were used in the Northwest Oilfield of Sinopec recently. In the key exploratory well Qieshen 1, the key parts of the 2 layer tapered casing string, with features such as high tensile resistance, high internal pressure resistance and high sulfur resistance, helped the 2nd layer casing enter the Qieshen 1 well smoothly, and played an important role for the well in breaking many domestic records. Qishen 1 is a key risk exploration well deployed by Sinopec in the hinterland of Tarim Basin. With a drilling depth expected to exceed 8,000 meters, the ultra-deep, ultra-high temperature, high-pressure and high-sulfur well is a typical ultra-deep complex well. It has set domestic records of similar casings in casing depth, hanging weight, and length of the open-hole section. The complex geological structure of the site placed even higher demands on the casing quality as well as on-site casing operation for making these records.