Petroleum unit converter
Twenty-one families of upstream units, converted in one place — including the awkward ones like bbl/ft, psi/ft and millidarcy.
Units & conversion
Mud weight, gradient & hydrostatic pressure
Mud weight in any unit to a gradient and a hydrostatic pressure at any TVD — and the same calculation run backwards to an equivalent mud weight.
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How it is calculated
- P = ρ · g · TVD, with g taken as 9.80665 m/s² and every unit converted to SI before the multiplication.
- Gradient is ρ · g, reported in psi/ft, bar/m and kPa/m.
- In reverse mode the given pressure less the surface pressure is divided by g·TVD to give the equivalent mud weight.
Standards it speaks
Where this stops being true
This is a static column of one uniform fluid. It is not ECD: it ignores annular friction, cuttings loading, gel strength on breaking circulation and surge or swab. A well that is static at this number can be losing returns while circulating. For the circulating figure use the ECD tool.
The capability that automates this
- DR-04Wellbore Stability PredictionPredicts the mud weight window that keeps the hole open — not too light and it caves, not too heavy and it fractures.
- DR-06Real-Time Torque, Drag & HydraulicsCompares what the string should weigh and how hard the pumps should work against what is actually measured, and flags the gap.
Related tools
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One date in three calendars, for the daily drilling report that is dated in one and the contractor report that is dated in another.
Well volumes & circulation time
Annular and string volumes section by section, then the strokes and the minutes to bottoms-up and to a full circulation.