Static Analysis Output Listing - CAESAR II - Reference Data

CAESAR II Applications Guide

Reference Data

Analysis produces the following reports.

Hanger report

  • The output listed in the example includes significant output only.

  • Notes, which discuss the results, are included with each report.

  • The following reports are included in this output:

    • Complete Hanger Report

    • Operating Case Displacement Report

    • Installed (Sustained) Case Displacement Report

    • Operating & Installed Restraint Summary

    • Sustained Stress Summary and Stress Report

    • Expansion Stress Summary and Stress Report. (Stresses in the operating condition are not used in B31.3 analyses)

The hot load of 1209 lbf. was calculated in the initial weight run (load case 1) with a rigid Y restraint installed at node 28. The load on the restraint was 1209 lbf.

A 1209 lbf. +Y load replaced the rigid Y restraint at 28 and then an operating case was analyzed (load case 2). Node 28 moved 0.750 in. in the +Y direction in this analysis.

CAESAR II selected an appropriate mid-range spring from the Anvil hanger table. The size 10 spring has the hot load of 1209 lbf. in its working range. This mid-range spring (short range springs were excluded) has a spring rate of 260 lbf./in. Assuming that node 28 moves 0.750 inches between the cold to hot position, this increases the spring load by (.750)(260) or 195 lbf. The cold load on the size 10 spring is 1222+195 or 1404 lbf. This cold load is also within the working range of the size 10 spring.

Displacements reports

The deflections of nodes 5 and 40 were entered as input. Node 28 again moves up 0.750 in. in the Y direction with the spring installed.

Look at the zero position of nodes 5 and 40. When the imposed displacements are not included in the analysis, the node is fixed with zero movement in each of the defined directions.

Restraint summary

The restraint report lists the piping forces and moments on the restraint. It does not list the restraint loads on the piping. The loads at node 5 are the nozzle loads and can be used without sign change to check the API 610 allowable loads. Loads for node 40 can be used to check the vessel stresses due to the nozzle loads.

The loads at 28 show the operating load and the actual installation load (with contents) for the selected spring. The spring carries the designed load of 1209 pounds in the operation condition.

The +Y restraint at node 35 shows it is nonlinear nature. In the cold condition, the restraint is active. As the piping moves to the hot position, it disengages from the support. Refer back to the displacement reports to confirm that the Y displacement is 0.0 in the installed (sustained) condition and +Y in the operating condition.

The summary shows that the sustained stresses throughout the system are below their allowable values. The sustained stress closest to its allowable limit is at the vessel node 40.

Stress reports

The summary shows that the expansion stresses throughout the system are below their allowable values. The expansion stress closest to its allowable limit occurs along the header at the node 10 tee.

For the stress detail report, note the application of the tee and bend stress intensification factors. The tee at 25 has SIFs other than 1.00 for all three listings: 25 to 28, 20 to 25, and 25 to 620. Bend SIFs are applied only on the bend side of the node compare node 28 on 25-28 and 28-29. No stresses are listed for rigid elements as no valid moment of inertia is provided for these elements.