This standard is issued under the fixed designation A 200; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon ( ュ) indicates an editorial change since the last revision or reapproval.

1.Scope

1.1This specification covers several grades of minimum-wall-thickness, chromium-molybdeum
and chromium-molybdenum-silicon,seamless, hot-finished and cold-finished,intermediate alloy-steel still tubes, for use in carrying fluids at elevated temperaures and presures in various types of heaters, in which the tubes may be subjected to a furnace temperature higher than that of the contained fluid.
1.2 This specification covers tubes 2 to 9 in., (50.8 to 228.6 mm) inclusive, in outside diameter and over 0.220 in. (5.59 mm)in minimum wall thickness.
1.3 Where butt welding is used to obtain length longer than single length normally produced in the mill, Specification A 422 shall cover the requirements for butt welds.
1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.