API SPEC 2MT1
Specification for Carbon Manganese Steel Plate with Improved Toughness for Offshore Structures
|Publication Date:||1 September 2001|
This specification covers one grade of intermediate strength steel plates, though 2½ in.thick, for use in welded construction of offshore structures. These steels are intended for fabrication primarily by cold forming and welding as per API Spec 2B. The welding procedure is of fundamental importance, and it is presumed that procedures will be suitable for the steels and their intended service. Conversely, the steel should be amendable to fabrication and welding under shipyard and offshore conditions. These steels are suitable for use in selected portions of offshore structures, which must resist impact and plastic fatigue loading. When hot or warm forming or PWHT above 1100°F is anticipated for accelerated cooling (AC) or quenched and tempered (QC) plates, S9 should be invoked, (italics added per ASTM A913).
The primary use of these steels is for Class "B" applications as defined in API RP 2A. API Specs 2H, 2W, and 2Y cover other steels providing improved mechanical properties and toughness for Class "A" applications and should be used where substantial z-direction stresses are expected.