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Lag Time & Bottoms-Up Calculator

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Geology & Drilling

Annular Velocity & Hole Cleaning: Getting Cuttings Out of the Hole

Why annular velocity determines hole cleaning efficiency. Minimum AV targets, cuttings slip velocity, deviated well challenges, and flow rate optimization.

Geology & Drilling

Lag Time & Bottoms-Up: Tracking What Comes Out of the Hole

How to calculate bottoms-up time and pump strokes. Why lag time matters for mud logging, gas shows, well control, and knowing what is really happening downhole.

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Geology & Drilling Live

Hydrostatic Pressure Calculator

Calculate hydrostatic pressure from mud weight and true vertical depth. Oilfield imperial (ppg/psi) and metric (SG/kPa) units with overbalance analysis and pressure gradient.

Geology & Drilling Live

Equivalent Circulating Density Calculator

Calculate ECD from mud weight and annular pressure loss. Determine safe operating window between pore pressure and fracture gradient for wellbore stability.

Geology & Drilling Live

Annular Velocity Calculator

Calculate annular velocity and flow rate for hole cleaning. Enter hole/pipe diameters and pump rate to get AV in ft/min with cuttings transport analysis.