12.1 For the purpose of determining compliance with the specified limits of property requirements, an observed value or a calculated value shall be rounded in accordance with the rounding method of Practice E29.

This specification covers tantalum and tantalum alloy seamless and welded tubes of the following grades: UNS Grade R05400 which is unalloyed tantalum, powder-metallurgy consolidation, UNS Grade R05200 which is unalloyed tantalum, vacuum melted, UNS Grade R05252 which is tantalum with 2.5% tungsten alloy, vacuum melted, UNS Grade R05255 which is tantalum with 10% tungsten alloy, vacuum melted, and UNS Grade R05240 which is tantalum alloy with 60% tantalum, 40% columbium, electron-beam furnace or vacuum arc melted, or both. Seamless tube shall be made by any seamless method and the welded tube shall be made from flat-rolled product by an automatic or semiautomatic fusion welding process with no addition of filler metal. Mechanical properties such as ultimate tensile strength, yield strength, and elongation shall be determined by tensile, flare, and reverse flattening tests. Nondestructive tests such as hydrostatic test, pneumatic test, helium leak test, and ultrasonic test shall be done as well.