Modifications resulting from flanged ends using CODETI
Modifications resulting from flanged ends are permitted in the code for all bends, including widely spaced miters.
Calculate stress intensification factors (SIFs) for intersections using CODETI
CODETI provides two separate equations to calculate the in-plane and out-plane SIFs for intersections.
Calculate expansion stress using CODETI
CODETI provides an equation to calculate the expansion stress. This equation does not include calculations for the longitudinal stress due to axial loads in the pipe. CAESAR II does not include the F/A longitudinal stress component for stress in the expansion stress equation. You can change this by setting Add F/A In Stress to the configuration file. The software adds the F/A longitudinal stress component, by default, to the code stress component for all other stress categories.
Calculate the CODETI allowable stress limits
Use the equations below to calculate the stress allowables.
Expansion Allowable = F [1.25 (Sc + Sh)] - Sl
Sustained Allowable = Sh
Occasional Allowable = OCC * Sh
Where:
F = Cyclic Reduction Factor
Sc = Cold Allowable Stress
Sh = Hot Allowable Stress
Sl = Sustained Stress
OCC = Occasional Load Factor from Configuration - Defaults to 1.15
Pressure stiffening using CODETI
Pressure stiffening of bends is automatically included as directed by the code. You can disable pressure stiffening on bends in the analysis by excluding the Use Pressure Stiffening option in the configuration file.
SIFs and flexibility coefficients using CODETI
Flexibility coefficients and SIFs are phased in for bends with an included angle between 15° and 45°. The default value for bends smaller than 15° is 1.0.
SIFs and fabricated tees using CODETI
To determine the SIF of a fabricated tee having an angle of incidence other than 90°divide it by (sin a)3/2
CODETI recommended occasional load factor values
Recommended occasional load factor values are 1.15, 1.2, and 1.3, as per Code Table C3.3.
CODETI requires that when "the design temperature is such that the creep characteristics are determinant, and if a section of the piping presents locally weaker characteristics," the sum of the primary and secondary stresses must not exceed the value flexibility factor (from Section C1.4.3). CAESAR II does not implement this requirement and is left for you to verify.
CODETI reducer default values
The default SIF value is 1.0. The default flexibility factor value is 1.0.