Calculate stress intensification factors (SIFs) for intersections using HPGSL
HPGSL provides two separate equations to calculate the in-plane and out-plane stress intensification factors (SIFs) for intersections.
Calculate expansion stress using HPGSL
HPGSL 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 including the Add F/A In Stress option in the configuration file. The program adds the F/A longitudinal stress component, by default, to the code stress component for all other stress categories.
HPGSL girth butt welds default value
The default SIF value for a girth butt weld is 1.0. This is also Markl’s original basis for SIFs.
Calculate socket welds using HPGSL
HPGSL makes no distinction between socket welds with undercut and socket welds without undercut. Codes that do differentiate use 1.3 for socket welds with no undercut, and 2.1 for all others. Unless you are specifying a fillet weld leg length, use a default SIF value of 1.3.
Calculate the HPGSL stress allowables
Use the equations below to calculate the stress allowables.
Expansion Allowable |
= |
f [ (1.25/Eff)(Sc+Sh) - Sl ] |
Sustained Allowable |
= |
Sh/Eff |
Occasional Allowable |
= |
(Occ)*Sh/Eff |
Where:
f = Cyclic Reduction Factor
Eff = Weld Joint Efficiency Minimum Wall Thickness Only
Sc = Ambient (cold) Allowable Stress, the minimum of 0.66Syc or 0.33Suc
Sh = Hot Allowable Stress, the minimum of 0.66Sy or 0.33Su
SI = Sustained Stress
Occ = Occasional Load Factor Default is 1.33
When specifying a corrosion allowance, do not use a corrosion value in the sustained and occasional stress calculations.
HPGSL reducer default values
The default SIF value is 1.0. The default Flexibility Factor value is 1.0.
HPGSL Pressure effects
Pressure effects on miters are allowed in this piping code.
Seismic Analysis
HPGSL uses load cases defined by KHK.