💧 INTERACTIVE CALCULATOR

Deep Hole Drilling Coolant Calculator

Estimate required coolant pressure, flow rate and pump power for gundrilling, BTA or ejector drilling — by drill diameter and depth-to-diameter ratio.

CALCULATOR

Pressure, Flow & Pump Power

Method

Drill diameter D (mm)

L/D depth ratio

—

bar

Required coolant pressure

—

L/min

Required flow rate

—

Pump power estimate

Estimates based on published tool-maker guidance. Flow is the critical parameter for ejector (Venturi) drilling; pressure for small-diameter gundrills.

REFERENCE

What the Numbers Mean

💡 Rules of thumb: Gundrilling pressure falls as diameter grows (≈1500 psi at 3 mm to ≈300 psi at 25 mm); BTA leans on flow (50–500+ L/min) at 15–100 bar; ejector needs high flow at only 10–50 bar because the Venturi effect is flow-driven. Below ~8 bar, an ejector's suction collapses.

⚠️ Verify flow at the tool tip, not the gauge: a high-pressure pump with inadequate volume won't clear the bore. See Coolant System Guide and Coolant Filtration.