Well Control
A kick is an influx of formation fluid into the wellbore because formation pressure has exceeded hydrostatic pressure. Every crew member must know the warning signs — early detection means a manageable situation.
Kick Recognition
✅ Normal — Keep Drilling
Steady pit volume. Returns match pump output. Normal gas levels. Stable ROP and torque.
⚠ Warning Signs
Increasing pit volume (0.5–2 bbls). Drilling break. Increase in return flow while pumps are constant.
🔶 Shut In Now
Pit gain greater than 2 bbls. Well flowing with pumps off. Any positive SIDPP/SICP after shut-in.
🚨 Emergency
Uncontrolled flow at surface. BOP failure. Evacuate and activate emergency response plan immediately.
Shut-In Procedure
Immediately pick up off bottom. Stop making hole the moment a kick is suspected. Raise the string to clear the kelly/top drive.
Close the annular BOP (soft shut-in) or pipe ram (hard shut-in) per company procedure. Close the choke. Notify toolpusher and company man immediately.
Allow pressures to stabilize (15–30 min). Record SIDPP, SICP, and pit gain volume — your inputs for the kill sheet.
KMW = OMW + (SIDPP ÷ (0.052 × TVD)). Add safety margin per company policy. Calculate ICP and FCP for the kill sheet.
Driller's Method or Wait-and-Weight — both are valid, follow your company's approved procedure. See comparison below.
Confirm zero pressure and no flow before resuming. Investigate root cause before drilling ahead.
Driller's Method vs Wait-and-Weight
| Method | Process | Advantage | Disadvantage |
|---|---|---|---|
| Driller's Method | Circulate the kick out first at original mud weight while holding casing pressure constant, then weight up and circulate to TD in a second circulation. | Can begin immediately — no time spent mixing kill mud first | Two full circulations required; more time on well overall |
| Wait-and-Weight (Engineer's Method) | Prepare kill-weight mud first, then circulate the well in a single stage using the weighted mud. | Single circulation — often faster overall, less annular pressure exposure | Requires time to mix sufficient kill mud volume before starting |
Both methods are industry-accepted and taught in IWCF/IADC well control certification. Which one is used depends on company policy, kick severity, and available kill mud on location. Use the kill sheet calculator to run the actual numbers for either method.