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Annular Velocity Calculator

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Geology & Drilling

ECD Explained: Equivalent Circulating Density in Drilling Operations

What ECD is, why it matters more than static mud weight, how annular pressure losses push you toward the fracture gradient, and how to manage the operating window.

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

Lag Time & Bottoms-Up Calculator

Calculate bottoms-up lag time and strokes from well geometry and pump data. Track drilling fluid returns for mud logging, gas detection, and wellbore monitoring.