The pipe stress and ground motion are a method that would yield reasonable stress estimates by simplifying this source into an equivalent parallel line or point source.
Prediction methods developed are general enough to provide reasonable stress estimates over a wide range of scaled parameters. Some exceptions to the general procedures will exist as a result of explosive geometric configurations i.e. 90 degrees.
Minimum distance from the pipeline to the nearest explosive charge must be greater than two times outside pipe diameter.
Maximum allowable angle between pipe and explosive line must be less than 90Λ
π΄ β Distance from the Charge to the Pipeline(ft)
π β Equivalent Standoff Distance(ft)
π΅ β Angle Between Pipe and Grid,deg., convert to Radians=π΅(0.0175)
π β MAOP β Maximum Allowable Operating Pressure(psi)
π· β Pipeline Outside Diameter(in)
π‘ β Pipe Wall Thickness(in)
πβΒ β Hoop Stress(psi)
πΏΒ β Total Length of Explosive Line(ft)
πΏ1Β β Spacing Length Between Charges in Explosive Line(ft)
πΒ β Total Charge Weight(lbs)
π1Β β Weight of Single Charge(lbs)
π1Β β Number of Charges in Explosive Line
ππΒ β Maximum Circumferential =Β ππΒ β Maximum Longitudinal Stress(psi)
πΒ β Equivalent Energy Release Ratio
πΒ β Weight of Single Charge(lbs)
πΈΒ β Modulus of Elasticity
π‘Β β Pipe Wall Thickness(in)
ππ‘Β β Combined Hoop and Circumferential Stress(psi)
Blasting Conditions for combined Stress Level
πΆππππππ>%ππππβNOT ACCEPTABLE/πΆππππππ<%ππππβACCEPTABLE
Input Parameters
To create a new case, click the βAdd Caseβ button
Select the Angled Grid Explosive Charge application from the Pipe Blast module.
Enter Case Name, Location, Date and any necessary notes.
Fill out all required fields.
Make sure the values you are inputting are in the correct units.
Click the CALCULATE button.
Pipe Outside Diameter
Pipe Wall Thickness
Specified Minimum Yield Strength
Maximum Allowable Combined Stress Level – SMYS
Manufacturer
Explosive Type
Equivalent energy release ratio
MAOP – Maximum Allowable Operating Pressure
N1 – Number of Charges in Front Row of Explosive Grid
N2 – Number of Rows Making the Explosive Grid
L1 – Spacing Length Between Charges in Explosive Line
L2 – Spacing Length Between Explosive Lines
W1 – Weight of Single Charge
n – Equivalent Energy Release Ratio
A – Distance of the Nearest Charge to Pipeline
B – Angle Between Pipe and Grid
Outputs/Reports
View the results.
If an input parameter needs to be edited be sure to hit the CALCULATE button after the change.
To SAVE, fill out all required case details then click the SAVE button.
To rename an existing file, click the SAVE As button. Provide all case info then click SAVE.
To generate a REPORT, click the REPORT button.
The user may export the Case/Report by clicking the Export to Excel/PowerPoint icon.
To delete a case, click the DELETE icon near the top of the widget.