This specification covers seamless and welded steel pope@ seamless and welded open-hearth-iron pipe@ and welded wrought-iron pipe. It includes standard-weight threaded pipe; and standard-weight plain-end@ regular-weight plain-end@ special plain-end@ extra-strong plain-end@ and double-extra-strong plain-end pipe. The sizes and wall thicknesses applicable to the various processes of manufacture under this specification are indicated in the dimensional tables herein. Dimensional requirements on threads and gages and stipulations on gaging practice also are covered@ as well as requirements for couplings and thread protectors. Nothing contained in this specification is to be construed as granting any right@ by implication or otherwise@ for manufacture@ sale@ or use in connection with any method@ apparatus@ or product covered by letters patent@ nor as insuring anyone against liability for infringement on letters patent.