1.1 This specification covers chromium-tungsten-molybdenum-vanadium, with or without tantalum, alloy steel plates intended primarily for welded boilers and pressure vessels designed for elevated temperature service.
1.2 Plates are available under this specification in two grades having different alloy contents as follows:
|Grade||NominalChromiumContent, %||NominalTungstenContent, %||NominalMolybdenum Content, %||NominalVanadiumContent, %||NominalTantalumContent, %|
1.3 The maximum thickness of plates is limited only by the capacity of the composition to meet the specified mechanical property requirements.
1.4 The specification is expressed in both inch-pound units and in SI units; however, unless the order specifies the applicable "M" specification designation (SI units), the plates are furnished to inch-pound units.
1.5 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system is to be used independently of the other.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
A20/A20M Specification for General Requirements for Steel Plates for Pressure Vessels
A435/A435M Specification for Straight-Beam Ultrasonic Examination of Steel Plates
A577/A577M Specification for Ultrasonic Angle-Beam Examination of Steel Plates
A578/A578M Specification for Straight-Beam Ultrasonic Examination of Rolled Steel Plates for Special Applications
ICS Number Code 77.140.20 (Steels of high quality)
UNSPSC Code 30102204(Steel plate )