MILLWRIGHTS

Millwright

Drive ratios, rotating equipment and alignment math. Use the tabs below to switch between working calculators and quick field-reference material.

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Millwrights

Pulley RPM

Calculate driven RPM from driver RPM and pulley diameters.

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Millwrights

Shaft Speed

Calculate shaft surface speed from diameter and RPM.

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Field-reference aid. Use approved drawings, current codes/standards, manufacturer data and job-specific procedures for final decisions—especially for lifting, electrical, pressure, fire-protection and life-safety work.

Pulley speed

Driven RPM = driver RPM × driver diameter ÷ driven diameter (ideal, no slip).

Gear/sprocket ratio

Driven RPM = driver RPM × driver teeth ÷ driven teeth.

Alignment

Soft-foot, thermal growth and manufacturer tolerances matter in addition to measured offset/angular error.

Torque

Always use equipment/fastener manufacturer torque requirements where specified.

Need a specific table or takeoff chart?

Send us what you use in the field and we can build it into this trade section.

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