PIPELINE STRESS ANALYSIS WITH CAESAR IIby Andrey Puruhita PIPELINE STRESS ANALYSIS WITH CAESAR II What the different with piping stress ? Pipeline burried modeling Anchor block restrain Load case combination & result . 4 for liquid & B31.The difference of piping & pipeline stress analysis Piping modeling • Code requirement shall use ASME B31.8 for gas transmission • Usually Underground • Shall use anchor block as a restrain from abovegroundunderground conversely .3 • Aboveground • Many support or restrain needed Pipeline modeling • Code requirement use ASME B31. Burried Pipe • Buried pipe deforms laterally in areas immediately adjacent to changes in directions • In areas far removed from bends and tees the deformation is primarily axial . Soil Models • Describe the sections of the piping system that are buried.PIPELINE BURRIED MODELING • The Buried Pipe Modeler is started by selecting an existing job.Convert Input . and then choosing menu option Input-Underground from the CAESAR II Main Menu • Enter the soil data using Buried Pipe . and define any required fine mesh areas using the buried element data spreadsheet • Convert the original model into the buried model by the activation of option Buried Pipe . Input soil models . . • It allows the user to define mesh spacing at specific element ends. • It allows the input of user defined soil stiffnesses .The buried element description spreadsheet serves several functions • It allows the user to define which part of the piping system is buried. Burried pipe example . there were a change direction from underground to aboveground • In this situation pipeline must be installed with anchor block before and after aboveground pipe .Anchor Block Restrain • Pipeline with a long distance needs block valve. Why we need anchor block ? • To prevent stress failed on block valve due to axial deformation of a long pipeline . Example of block valve modeling Anchor block Anchor block . Load Case Combination • To check stress analysis on pipeline shall use several load case combination as folow : . • Sustain Load ( W + P) • Thermal Load (T) • Combination Load ( W + T + P) . 60000. 1. 60000.000 / 1.) OPE STRESS %: 21.000 10300. 0. 18.4 @NODE 20 • • • • • • 60 70 80 90 90 95 1357. 60000.)----(lb. 3255.06 @NODE 90 STRESS: 12636. 0. 1.000 / 1. . 1.000 12636. 17.000 / 1. 1461. 919.2009 --Stress(lb. 0.000 / 1.000 12636. 60000.in. 18.000 / 1. 1.Caesar Stress Result • • • • • • • • • • • • CAESAR II STRESS REPORT FILE:FOR TUTORIAL CASE 3 (OPE) W+T2+P1 DATE:OCT 1. 60000. 1.2 @NODE 130 3D MAX INTENSITY: 30120.0 @NODE 49 AXIAL STRESS: 9455. 21.)-ELEMENT BENDING TORSION SIF'S ALLOWABLE NODES STRESS STRESS IN/OUT PLANE STRESS STRESS % HIGHEST STRESSES: (lb.0 BENDING STRESS: 3254.000 / 1./sq.000 12085.000 10842. 3255.000 10739. 2703.in.4 ALLOWABLE: 60000. 0. 0. 60000./sq. 1.8 @NODE 90 TORSIONAL STRESS: 0. 21. 0.in. 20./sq. THANK YOU .