Extended Fatigue Exemption Rules for Low CR Alloys into the Time-Dependent Range for Section VIII Division 2 Construction
NORMA vydána dne 2009
Označení normy: ASME STP-PT-025:2009
Datum vydání normy: 2009
Počet stran: 65
Přibližná hmotnost: 195 g (0.43 liber)
Země: Americká technická norma
Kategorie: Technické normy ASME
A number of alloys have applications slightly into the creep range that are in cyclic service, such as process reactors. The 2007 edition of Section VIII, Div 2 provides allowable stresses for these materials, which may be controlled by creep properties. However, the fatigue design rules and fatigue exemption rules are not applicable, precluding construction of vessels using these materials at temperatures above 370°C (700°F). This report provides a simplified approach for exemption of low chrome alloys from fatigue analysis that are slightly into the creep range.