What is FE-SIF?

Classical pipe stress analysis programs use piping beam elements that are constrained to the limitations inherent with beam elements. For example, beam elements do not capture the effect of ovalization where the cross section of the pipe deforms away from the unloaded round geometry. To compensate for the limitations, correction factors are applied to the beam models to more closely match the flexibility and stresses of the pipe to reality. The correction factors, flexibilities and stress intensification factors (SIFs), are based on analytical and empirical relations correlated to piping component geometries. The accuracy of the correlations depends on the geometries of the piping components.

FE-SIF brings finite element analysis (FEA) to the piping designer's toolkit to provide accurate SIF and flexibility factor calculations for all geometries and load conditions. FE-SIF can be used to calculate correction factors for components outside the correlational limits of standardized design codes and for components with no guidance in the design codes.

Using FE-SIF

FEA technology is well understood and reliable but has been used sparingly because general purpose finite element software programs have been too complicated to input the model and to interpret the results on a daily basis. FE-SIF is designed to calculate SIFs and flexibilities with minimal input to generate reliable results that can be easily transferred to pipe stress programs.

The input interface provides visual guidance that indicates the geometric input as you proceed to build the model The results are presented in tables that are easy to understand and apply to your pipe stress program.

What geometries can be analyzed?

Parent piping component

• Conical
• Cylinder
• Elliptical
• Flat
• Flanged and dished
• Hemispherical

Branch or nozzle position

• Radial
• Lateral
• Hillside

Branch or nozzle type

• Straight (unreinforced)
• Pad reinforced
• Barrel (self-reinforced)

What results are calculated?

Graphical Results

FE-SIF includes the FE/Pipe graphical viewer that can be used to interrogate calculated displacement and stress patterns. The viewer provides insight into the interaction between loading and resulting displacement.