2. TEMA Clause RCB-5.141 "Backing Device Thickness(Type S)" :- There are
some empirical formulas given for calculating backing ring thickness
depending on the style given in "Figure RCB 5.141".
As design code for Heat Exchanger is ASME Section VIII Div 1 (For
pressure upto 3000 PSI),Appendix 2 of this code is mandatory for
calculating backing ring thickness.
Query - ASME Section VIII Div 1 Appendix 2 Clause 2-9 "Split Loose
Flanges" states that 200% of total moment shall be considered for
single split and 75% of total moment shall be considered for double
split flange or flange ring.
However TEMA consider this moment factor based on style given in
"Figure RCB 5.141".But for style A & D,TEMA does not consider any moment
factor as considered in style B.Also TEMA is not specifying moment
factor for double split flange or flange ring.
Since TEMA is the standard and the manufacturer has to comply with
code requirements,this inconsistency causes confusion.Request
clarification.
Split Factor in Backing Ring Calculation
