Workover · Intervention
Well Kill
Stopping a well from flowing by filling it with a fluid dense enough to hold back the formation.
What it does
Done before a workover that replaces the tubing. Kill weight fluid is pumped in to overcome the formation flow, or the influx is circulated out. Bullheading forces fluid into the formation and is used when circulation is not possible or H2S is suspected.
Basics
| Kill weight | Density just high enough to stop pore fluid flow |
| Methods | Pump kill fluid, circulate out, or bullhead |
| Bullhead risk | Fluid goes to the weakest formation |
Common failures
- Kill fluid lost to a weak formation
Troubleshooting
- Symptom
- Fluid level drops after the kill
- Likely cause
- Losses to the weakest zone
- What to check
- Keep the hole full and monitor, and review the fluid density