ASME B31.3 Appendix D, Table D300 provides formulas to calculate SIF for fittings and branch connections etc. For Welding Tee, the SIF (out-of-plane for example) i= 0.9/h2/3 where h= 4.4*T/r2. In order to use these formulas legitimately, two geometry rules have also been given as shown on the same Table. These rules address requirements on crotch radius and crotch thickness. i.e. 1) rx>=1/8Db, 2) Tc>=1.5 T. If these two geometry rules are not met, note (11) shall apply; which will change h from h1= 4.4*T/r2 to h2=T/r2. Subsequently, the SIF, i2 will be increased to (4.4)^2/3 or 2.685 times the i1.

Caesar II assumes that all welding tees meet those geometry rules and has been using formulas as shown on Table instead of Notes (11) for calculating SIF. In other word, the default is h1= 4.4*T/r2 as shown on Table, and program provides no option for h2=T/r2 as shown on Notes (11). Stress engineer has to correct the stresses at welding tee manually as required only if he(she) knows what kind of welding tees are in the piping system. Piping specification group has been instructed to put these geometry rules in piping specification, so that default formula (h= 4.4*T/r2 ) in Caesar could be validated.

ASME B31.3b-2001 Addenda has been issued on August 31,2001 with Mandatory date of March 1, 2002. This issuance made revision on this subject as follows:

1. h= 4.4*T/r2 with geometry rules (rx>=1/8Db and Tc>=1.5 T) has been moved from face of Table to Note (11).
2. h= 3.1*T/r2 is the revised formula for calculating h, as shown on face of Table 300, without any geometry rule restrictions.

Now, the question is how will Caesar II build in these revised rules in the program? Will formula as shown on face of Table (h= 3.1*T/r2 ) still be the default? or formula as shown on Note (11) be the default? or, options will be provided for user's choice.