| Applies To | |||
| Product(s): | AutoPIPE | ||
| Version(s): | All | ||
| Environment: | N/A | ||
| Area: | Analysis | ||
| Original Author: | Bentley Technical Support Group | ||
| Date Logged & Current Version | Aug. 2015 09.06.02.06 | ||
Problem:
When Test Pressure = None, Test Temperature = None, and/or Design Case = "None" and trying to press the "Update Test Pressure" button from the "B31.3 Test Pressure" section of the Hydrotest dialog,
the following warning(s) may be displayed:
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Bentley AutoPIPE
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Please select a valid design case to be used for B31.3 test pressure update.
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OK
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AND / OR
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Bentley AutoPIPE
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Please select a valid test pressure case for B31.3 test pressure update.
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OK
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AND / OR
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Bentley AutoPIPE
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Please select a valid test temperature case for B31.3 test pressure update.
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OK
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Why and How to avoid it?
Solution:
Note:
1. Pressing the "Update test pressure" button will automatically update all the Test Pressure case values (i.e. P1, or P2, or ..Pn) indicated near the top of the dialog based on the calculation mentioned in the AutoPIPE help.
2. Please see the following file installed with
AutoPIPE CONNECT v.10.00.00.10 and Higher
Help > Contents> Contents Tab> Bentley AutoPIPE> Supplemental Documentation> Hydrotest Tutorial
AutoPIPE V8i 09.06.01.10 and lower:
C:\Bentley \AutoPIPE V8i SELECTseries \Documents \ Hydrotest Tutorial_rev_6.pdf
3. The Design Pressure / Temperature is the operating condition that the piping will typical operate at per normal conditions. These values are typically lower than the Testing Press/Temp.
4. The Test Pressure / Temperature is the operating condition that the piping will be subjected to during the testing phase; ensure the pipe does not leak / fail per peak conditions. These values are typically higher values by a set factor above the Design Press / Temp values. Since the user must input all load case values (T1.. Tn and P1..Pn) this factor is not entered at any time. The actual values entered should have taken this factor into consideration. Recommend the user to provide detailed descriptions under Load> Load Case Descriptions to be used as a reference,
As noted in the message(s) above, "None" is not a viable selection for any of the 3 settings mentioned above when pressing the "B31.3 Test Pressure" command-"Update test pressure" button on the right.
The user must select a Testing Pressure load case, a Testing Temperature load case, and a DESIGN operating condition pair. This Design operating condition is set by selecting a Pressure / Temperature load set pair with the same number (i.e. P1/T1, P2/T2, P10/T10, ...Pn/Tn) from the "Design case" drop down listing as shown below:
Note:
Typically the Testing Press / Temp does not equal the Design Press / Temp, these are usually different load case values. If the Testing and Design Press / Temp load cases are the same the following message is displayed:
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Bentley AutoPIPE
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These selected test pressure case is same as the pressue case selected for design case. This will update the design case pressure values to calculated test pressure values. Do you want to proceed?
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Yes No Cancel
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Ultimately no changes will be made to the Testing Pressure values because the ratio of "St / S" = 1.0, multiplied by Internal Design pressure = 1.0 x Dp = Dp = Tp. Therefore, recommend using different load cases for Design and Testing settings.
All 3 of these settings are required by the "B31.3 test pressure calculation", see AutoPIPE help for details on this calculation (suggest reviewing this help section to better understand this dialog box).
The selected Design Pressure / Temperature load case values currently entered will be used in the calculation of the "B31.3 test pressure calculation" . Again, suggest verifying the values of the selected Press / Temp. load set prior to pressing the "Update test pressure" button.
Note:
It is recommended to review the "B31.3 test pressure calculation" to better understand this dialog. The equation uses both Test Pressure / Temperature (specified at the top of the dialog box) and Design Pressure / Temperature (specified in the "B31.3 Test Pressure" area of the dialog box).
The user must select all 4 of these load cases when using the "B31.3 test pressure calculation" button. One of the few restrictions is that the Design Pressure and Temperature have the same load set number (i.e. P1/T1, P2/T2, P10/T10, ...Pn/Tn).
Example:
Original values in model:
Hydrotest settings, Testing Press / Temp = P1 / T1, Design Press / Temp = P2 / T2
After Pressing the "Update test pressure" button, select YES 2x, and the following will displayed:
Internal calculations based on AutoPIPE help Hydrotest equation:
And then the Testing Pressure is Automatically updated
When the hydrotest analysis is actually performed the new updated P1 load case value(s) in the model (ex. 90.5 psi) are multiplied by the Testing Pressure Case Factor (ex. 1.25) indicated on the dialog to calculate the actual Hydro test pressure to be used in the analysis (Hydrotest Pressure used = TP * Factor = 90.5 * 1.25 = 113.13 psi).
Conclusion:
The user must first enter the proper values into the Press / Temp load sets (P1/T1...Pn/Tn) that represent operating conditions to be analyzed. Recommend to identify the load cases to help understand what each load case represents (load> Load Case Descriptions). When using the B31.3 Test Pressure command, the user must configure the dialog per Design condition and Testing condition. Based on these settings, press the "Update test pressure" button to automatically update the Test pressure with a new internally calculated value.