Standard Specification for Steel Plates for Pressure Vessels, Produced by Thermo-Mechanical Control Process (TMCP)
|Publication Date:||10 April 2003|
|ICS Code (Flat steel products and semi-products):||77.140.50|
The TMCP method consists of rolling-reduction and cooling rate controls that result in mechanical properties in the finished plate that are equivalent to those attained using conventional rolling and heat treating processes, which entail reheating after rolling. A description of the TMCP method is given in Appendix X1.
Due to the inherent characteristics of the TMCP method, the plates cannot be formed at elevated temperatures without sustaining significant losses in strength and toughness. The plates may be formed and post-weld heat-treated at temperatures not exceeding 1200°F [650°C], providing the requirements of 6.1 are met.
The maximum permitted nominal thickness of plates furnished to this specification is 4 in. [100 mm] for Grades A, B, and C; and 1.5 in. [40 mm] for Grades D(Footnote 3), E, and F.
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 must be used independently of the other. Combining values from the two systems may result in nonconformance with this specification.
Footnote * - A Summary of Changes section appears at the end of this Standard.
Footnote 2 - For ASME Boiler Pressure Vessel Code applications, see related Specification SA-841/SA-841M in Section II of that Code.
Footnote 3 - ExxonMobile Upstream Research Company has patents pending concerning the use of chemistry ranges in ASTM A 841 Grade D, in combination with specific TMCP routes and/or specific microstructural features. Interested parties are invited to submit information regarding identification of alternatives to these patented items to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee. Which you may attend.