Investigation of fracture causes of the titanium alloy drill pipe in ultra-short radius horizontal well drilling

•The vulnerabilities in inspection methods of the current titanium alloy drill pipe standards were found.•There are many micro-cracks on the surface of titanium alloy drill pipes that cannot be detected according to the current standards.•The drill pipe body had slight deformation at the beginning of the oblique section for ultra-short radius drilling process.•Suggestions for improving the standard of titanium alloy drill pipe in such extreme ultra-short radius drilling condition were put forward.