A 6-inch and a half 5-knife wing drill bit, using 15 pieces of 1613BIM-1 0.3, drilled a small hole in Jiaxian, Yulin, 481-2001 meters from the Yanchang formation to the Shiqianfeng formation, with a footage of 1520 meters, pure drilling for 97 hours, and a speed of 15.67 meters /h.