The code allows you to reduce the SSIs based on more applicable data. Currently, AutoPIPE only lets you use SSI = 0.75SIF or SSI=1. ASME B31J allows you to reduce the SSI based on the following:

Where sustained stress or moment factors are required by the applicable Code (e.g., ASME B31.1, ASME B31.3), and in the absence of more applicable data, the directional sustained stress or moment multiplier is determined as follows:

1. For components in sketches 1.1 through 1.3 and sketches 3.1 through 5.1

• The multiplier can be taken as the component stress intensification factor (SIF).

2. For components in sketches 2.1 through 2.6

• The multiplier is conservatively taken as the smallest of the following three values:

• Option 1: 0.75 times the applicable stress intensification factor (SIF).

• Option 2: The ratio of the component's actual wall thickness to the nominal pipe wall thickness, multiplied by the square root of the applicable SIF (used when the component's wall thickness is greater than the nominal pipe wall thickness).

• Option 3: The square root of the applicable SIF (used when the component's wall thickness is less than or equal to the nominal pipe wall thickness).

In other cases you may want to use NozzlePRO or other FEA to calculate the SSI.