Casing Burst Pressure Calculator
Calculate internal pressure resistance and burst safety factors per API 5CT standards
Casing Properties
Enter casing dimensions and material grade
API 5CT Burst Formula
- Uses Barlow's formula with 0.875 wall factor
- Accounts for manufacturing tolerance
- Based on minimum yield strength
Burst Analysis Results
Enter casing parameters and click Calculate
Common Casing Burst Ratings
| Size | Weight | Grade | Burst (psi) |
|---|---|---|---|
| 7" | 26 lb/ft | N-80 | 6,340 |
| 9-5/8" | 47 lb/ft | N-80 | 6,870 |
| 9-5/8" | 53.5 lb/ft | P-110 | 10,900 |
| 13-3/8" | 68 lb/ft | N-80 | 5,020 |
Formula Reference
API Burst Pressure (Barlow's Formula)
P_burst = (0.875 x 2 x Y_min x t) / OD
Where:
P_burst = Internal yield pressure (psi)
0.875 = Wall thickness tolerance factor (12.5% reduction)
Y_min = Minimum yield strength (psi)
t = Nominal wall thickness (in)
OD = Outside diameter (in)
Safety Factor Calculation
SF = P_burst / (P_internal - P_external)
Net Internal Pressure = P_internal - P_external
Design Requirement: SF >= Design Factor (typically 1.1)
Casing Weight Estimate
Weight (lb/ft) = 10.68 x (OD - t) x t
Where dimensions are in inches