The difference of piping & pipeline stress analysis Piping modeling •
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Code requirement shall use ASME B31.3 Aboveground Many support or restrain needed
Pipeline modeling •
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Code requirement use ASME B31.4 for liquid & B31.8 for gas transmission Usually Underground Shall use anchor block as a restrain from abovegroundunderground conversely
Burried Pipe •
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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
PIPELINE BURRIED MODELING •
The Buried Pipe Modeler is started by selecting an existing job, and then choosing menu option Input-Underground from the CAESAR II Main Menu
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Enter the soil data using Buried Pipe - Soil Models
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Describe the sections of the piping system that are buried, and define any required fine mesh areas using the buried element data spreadsheet
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Convert the original model into the buried model by the activation of option Buried Pipe - Convert Input
Input soil models
The buried element description spreadsheet serves several functions
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It allows the user to define which part of the piping system is buried. It allows the user to define mesh spacing at specific element ends. It allows the input of user defined soil stiffnesses
Burried pipe example
Anchor Block Restrain •
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Pipeline with a long distance needs block valve, there were a change direction from underground to aboveground In this situation pipeline must with anchor block before aboveground pipe
be installed and after
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 :
