Single Point Explosive Charge

A single point charge is used in estimating the stress magnitudes to the pipe.

The minimum distance from the pipeline to the nearest explosive charge must be greater than two times the outside pipe diameter.

𝑅 − Distance from the Charge to the Pipeline(ft)

𝑃 − MAOP−Maximum Allowable Operating Pressure(psi)

𝐷 − Pipeline Outside Diameter(in)

𝑡 − Pipe Wall Thickness(in)

𝑆_ℎ − Hoop Stress(psi)

𝑆_𝑐 − Maximum Circumferential = 𝑆_𝑙 − Maximum Longitudinal Stress(psi)

𝑛 − Equivalent Energy Release Ratio

𝑊 − Weight of Single Charge(lbs)

𝐸 − Modulus of Elasticity

𝑡 − Pipe Wall Thickness(in)

𝑆_𝑡 − Combined Hoop and Circumferential Stress(psi)

Blasting Conditions for combined Stress Level
𝐶𝑎𝑙𝑆𝑀𝑌𝑆 > %𝑆𝑀𝑌𝑆 − NOT ACCEPTABLE/𝐶𝑎𝑙𝑆𝑀𝑌𝑆 <%𝑆𝑀𝑌𝑆 − ACCEPTABLE

Input Parameters

1. To create a new case, click the “Add Case” button
2. Select the Single Point Explosive Charge application from the Pipe Blast module.
3. Enter Case Name, Location, Date and any necessary notes.
4. Fill out all required fields.
5. Make sure the values you are inputting are in the correct units.
6. 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
• W1 – Weight of Single Charge
• n – Equivalent Energy Release Ratio
• R – Distance of the Charge to Pipeline

Outputs/Reports

1. View the results.
2. If an input parameter needs to be edited be sure to hit the CALCULATE button after the change.
3. To SAVE, fill out all required case details then click the SAVE button.
4. To rename an existing file, click the SAVE As button. Provide all case info then click SAVE.
5. To generate a REPORT, click the REPORT button.
6. The user may export the Case/Report by clicking the Export to Excel/PowerPoint icon.
7. To delete a case, click the DELETE icon near the top of the widget.

• Sh – Hoop Stress
• Sc-Maximum Circumferential = Sl-Maximum Longitudinal Stress
• St – Combined Hoop && Circumferential Stress
• S – Total Combined Stress
• Calculated Percent of SMYS
• Blasting Conditions for Combined Stress Level:

Related Links