Explicit geometry and mean kinematics
Roller-Chain Drive Geometry Calculator
Calculate ideal speed ratio, pitch-line speed, pitch diameters and a continuous chain-length estimate from user-supplied geometry. This page does not select a chain size, strand count, service factor or power rating.
Geometry and ideal mean rates
Ideal geometry
Here p and d are in millimetres, n is in rpm and v is in metres per second. These are nominal pitch geometry and ideal mean kinematics; they do not calculate dynamic capacity, wear or instantaneous chordal speed variation.
Continuous pitch-count estimate
The Renold Roller Chain Designer Guide publishes this familiar center-distance/chain-length selection geometry within a broader manufacturer process. L* is generally non-integer. Do not simply treat it as the installed link count: choose a realizable pitch count and recompute/adjust exact center distance, clearances and tensioning using the selected product procedure. Offset links and even-pitch preferences are product/design decisions, not an automatic rounding rule.
ISO scope
ISO 606:2015 specifies characteristics of short-pitch precision roller/bush chains and associated sprockets, including dimensions, tolerances, length measurement and strengths; it is published and under revision. ISO 10823:2004 with Corrigendum 1:2008, confirmed in 2024 and under revision, provides industrial roller-chain drive selection guidance for ISO 606 products under specified conditions and recommends supplier consultation where loading, environment and maintenance vary.
No ISO/manufacturer rating reproduced: the removed generic power table, speed scaling, tooth exponent, service factors, strand multipliers and speed limits had no identified normative/catalogue row. Obtain current ratings and correction factors for the exact manufacturer, chain series, lubrication and duty.
Checked example
p=19.05 mm, Z₁=19, Z₂=57, n₁=1000 rpm, C=600 mm gives i=3, n₂=333.333333 rpm, v=6.0325 m/s, d₁=115.738919 mm, d₂=345.811844 mm and L*=102.153444 pitches.
Nikolai Shelkovenko
Nikolai Shelkovenko is a vibration analysis engineer and the founder and CEO of Vibromera. For more than 15 years he has balanced rotating equipment in the field rather than on a test bench: mulchers, industrial fans, crushers, centrifuges, shafts and spindles. That work is what the Balanset instruments grew out of — they were designed as a tool a specialist can carry to the machine and use alone, on site, not as laboratory equipment. Vibromera was founded in 2017 and has been based in Porto, Portugal, since 2023. Development, assembly and support of the Balanset line all happen here. The flagship instrument is the Balanset-1A, a portable analyser for single- and two-plane balancing and for vibration diagnostics. Nikolai is personally involved in customer support, in working through difficult balancing cases and in the development of the software. He works with customers worldwide, in any language.
