API Spec 7-1 Second Edition PDF
This standard specifies the technical delivery conditions for rotary drill stem elements: upper and lower kelly valves, square and hexagonal kellys, drill stem subs, drill collars (steel and non-magnetic, round and spiral), heavy-weight drill pipe (HWDP), drilling and coring bit connections, and stabilizers.
This standard is not applicable to drill pipe and tool joints, rotary shouldered connection designs, thread gauging practices, or grand master, reference master and working gauges, and does not include or identify performance properties. A typical drill stem assembly applicable to this standard is provided.