Drilling Power and Torque Calculator
Estimate ideal drilling metal removal rate, net cutting power, input power and spindle torque using a specific cutting energy approximation.
Results use the inputs above; example values are illustrative and are not tool-specific speed/feed recommendations.
Formulas and Calculation Method
Q = π D² RPM fn / 4000 cm³/min; Pc = Q × kc / 60000 (kW); Pinput = Pc / η; T = 9550 Pc / RPM (N·m).
This simplified engineering estimate starts from the drilling material removal rate and assumes an effective specific cutting force entered by the user. Power and torque are then derived from volumetric cutting work. Tool geometry and actual cutting data can change the apparent specific cutting force substantially; manufacturer drilling-power calculations may use different coefficients and torque models.
Important Assumptions and Limitations
Approximation only, especially for multi-margin drills, indexable drills, pilot holes and changing engagement. Not suitable as a certified motor-sizing or safety assessment. Enter an appropriate effective kc or independently verified specific cutting energy.
Frequently Asked Questions
Is the kc value universal?
No. It depends on workpiece material, tool geometry, uncut chip thickness and other factors.
Does estimated input power equal the motor nameplate rating?
No. Nameplate selection requires allowances for overload, transient torque and other machine loads.
Need the Right Cutting Tool?
Match this calculation to your workpiece material, machine setup and required tooling dimensions. Explore ONMY tools or share your application for a quotation.
Explore Holemaking ToolsRequest a QuoteTechnical references: Machining Doctor — Drilling Formulas. Calculations are independently implemented for ONMY; source links do not imply endorsement.
