The Complete Balancing Series
Series guide. The balancing series in reading order: six articles from single-plane fundamentals to at-speed balancing of flexible rotors, seven calculators, and the knowledge check, each with a summary and a figure.
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Balancing Knowledge Check
Knowledge check. Twenty-two auto-scored questions on application, calculation, and judgment across the balancing series, open-book with lookup links, a per-article score breakdown, and a printable certificate at 80 percent.
At-Speed Balancing: Machines and Procedure
How flexible rotors are balanced at speed: the vacuum facilities that run them to service speed, correction planes chosen for the modes, the sequence of a job from setup to acceptance, and the influence coefficient method, plane by plane or in plane sets for modal balancing.
Plane Set Calculator
Interactive tool. Determines the plane set for modal balancing: the unbalance proportion and relative angle in each correction plane, from the planes' axial positions, the target mode, and the mode shapes, with a check of the set's authority over the mode. Companion to the at-speed calculator.
At-Speed Balancing Calculator
Interactive tool. Solves a complete at-speed or trim balancing job: up to five planes, plane sets for modal balancing, twelve probes, and six speeds, with influence coefficients fitted from every run, least-squares corrections weighted by acceptance limits, and a printable report.
At-Speed Balancing: The Fundamentals
Why a low-speed balance can be necessary but not sufficient: critical speeds and mode shapes, amplitude and phase through resonance, the line between rigid and flexible rotors, and the distributed unbalance that excites bending modes beyond the reach of two correction planes.
Low Speed Balancing Procedure
The shop balancing procedure from setup through correction: the measure-and-correct cycle, correction methods, splitting a correction between available angular positions, and the residual unbalance verification test that proves a balance independent of the machine’s calibration.
Residual Unbalance Verification Calculator
Interactive tool. Performs the residual unbalance verification test for one correction plane from 6, 8, or 12 test positions, returning the verified residual, calibration check, reading scatter, and a to-scale polar plot. SI and US units, with a printable record.
Balance Correction Splitting Calculator
Interactive tool. Splits a required balance correction between two available angular positions, returning the two component masses, the total mass, and the mass penalty of the split. SI and US units, with a printable record.
Low Speed Balancing Machines
How a low speed balancing machine works: the hard-bearing and soft-bearing architectures, the hardware that supports and drives the rotor, how measured amplitude and phase become unbalance vectors, and how to assess whether a machine is adequate for a particular rotor.