Ideal average-speed arithmetic
Roller-Chain Kinematic Frequency Calculator
Calculate shaft, tooth-engagement and chain-loop candidate frequencies for an ideal no-slip chain drive. The output locates spectral lines; it does not identify a defect.
Kinematic candidate lines
Arithmetic multiples of engagement rate
| Plusieurs | Fréquence | Cycles/min |
|---|
Multiples are frequency markers only; amplitude, sidebands or a matching line are not a diagnosis by themselves.
Ideal kinematic identities
fₑ is the mean rate at which chain pitches engage sprocket teeth. Dividing by the total pitch count gives the mean loop-circulation frequency: one identified link returns to the same reference position once per loop. The formula does not predict vibration amplitude.
Limites des normes
ISO 606:2015 specifies characteristics of short-pitch precision roller/bush chains and associated sprockets, including dimensions, tolerances, length measurement and strength. It is currently published but under revision. ISO 10823:2004 avec corrigendum 1:2008, confirmed in 2024 and under revision, gives industrial roller-chain drive selection guidance and explicitly notes that loading, environment and maintenance vary and supplier consultation is desirable. Neither official scope turns these candidate frequencies into fault diagnoses.
Tooth-count recommendations are application and product dependent. For example, the Guide de conception des chaînes à rouleaux Renold recommends 19 teeth as an ideal minimum in its selection method and at least 25 for high speed or impulsive loads. That does not create a universal threshold for all chain drives; use the applicable standard, supplier data and design conditions.
Diagnostic gate: use a verified speed reference and compare measured spectra, orders, time waveforms, modulation/sidebands, trends, load and inspection. A calculated line may contain normal engagement energy, structural response, another source or a defect-related modulation. Do not label wear, slack, misalignment, a tight link or severity from frequency coincidence alone.
Exemple vérifié
Z₁=17, Z₂=51, L=120, n₁=1450 rpm gives f₁=24.166667 Hz, fₑ=410.833333 Hz, floop=3.423611 Hz and n₂=483.333333 rpm.
