Well Control Kill Sheet
Well-control kill-sheet maths — kill mud weight, formation pressure, initial and final circulating pressures, MAASP and maximum allowable mud weight from the shoe leak-off test. Field and metric units, fully offline.
Open Well Control Kill Sheet →What is the well control kill sheet calculator?
A well-control calculator that runs entirely in your browser. It works out the kill mud weight (KMW) needed to balance a kicking well, the formation (bottom-hole) pressure behind the kick, the initial and final circulating pressures (ICP and FCP) for a driller's or wait-and-weight kill, and the pressure limits at the casing shoe — the maximum allowable annular surface pressure (MAASP) and the maximum allowable mud weight (MAMW) from a leak-off test. Field units (ppg, ft, psi) and metric units (SG, m, bar) are both supported, and every result updates as you type. Nothing is uploaded — the maths uses the standard IWCF/IADC kill-sheet relationships and stays on your device.
How to use Well Control Kill Sheet
- Choose your units — Use the Field / Metric switch at the top. Field is ppg, feet and psi; metric is specific gravity (SG), metres and bar.
- Pick a calculation — Select a tab — Kill weight, Circulating pressures or Pressure limits — for the value you need.
- Enter the shut-in readings — Type the original mud weight, shut-in drillpipe pressure and true vertical depth. For circulating pressures also enter the measured slow-circulating-rate pressure.
- Read the result — The main figure is your answer; the smaller line shows a helpful equivalent, such as the increase over the original mud weight.
Frequently asked questions
Where does the slow-circulating-rate pressure come from?
It is a measured value, not a derived one. Record the standpipe pressure while circulating at your chosen kill rate before the kick, and enter that reading. The tool never estimates it for you.
Which depth should I use?
Always true vertical depth (TVD). Kill mud weight, formation pressure and shoe limits all depend on vertical height, not on measured depth along a deviated hole.
How is the final circulating pressure found?
FCP is the slow-circulating-rate pressure scaled by the ratio of kill mud weight to original mud weight (FCP = SCRP × KMW ÷ OMW). Pressure steps down linearly from ICP to FCP over the surface-to-bit strokes.
What does MAMW from LOT tell me?
It converts a leak-off test into the heaviest mud weight the shoe can hold: the test mud weight plus the leak-off surface pressure spread over the shoe TVD. Use it to check whether your kill mud weight is safe.
Tips
- MAASP is the surface pressure that puts the casing shoe at its fracture limit — watch the annulus against it while circulating out a kick.
- Shut in fast and read a stable shut-in drillpipe pressure; a trapped or migrating gas reading will skew every downstream figure.
- The formation pressure shown equals the kill mud weight expressed as an equivalent mud weight at that TVD, so the two cross-check each other.