Downhole · Abandonment
Bridge Plug & Cement Cap
A mechanical plug set inside the casing just above an abandoned zone, with a column of cement placed on top of it.
What it does
The plug grips the casing and seals the zone below; the cement cap adds a second seal and keeps the plug from moving. Each plug is pressure tested before it is relied on.
Basics
| Set | Within 15 m above the perforations (Alberta) |
| Test | 7,000 kPa for 10 minutes |
| Cap | At least 8 m of class G cement, or 3 m of approved resin gypsum cement |
| Types | Permanent or retrievable |
Common failures
- Plug set on damaged or corroded casing that does not hold
Troubleshooting
- Symptom
- Pressure falls during the plug test
- Likely cause
- Plug or casing leak
- What to check
- Reset the plug higher on good casing and test again