What is ISO 1328‑2 about?

ISO 1328‑2 is the second part of the multi-series of international standard, that is applicable to the cylindrical gears for the ISO system of flank tolerance classification.

ISO 1328‑2 establishes a gear tooth classification system relevant to double flank radial composite deviations of individual cylindrical involute gears and sector gears.

Note: ISO 1328‑2 is applicable to gears with three or more teeth that have reference diameters of up to 600 mm.

Note: ISO 1328‑2 does not provide guidance on gear design nor does it recommend tolerances.

Who is ISO 1328‑2 for?

ISO 1328‑2 on ISO system of flank tolerance classification is relevant to:

Manufacturer and purchaser of the product gear
Mechanical engineers
Industries involved in gears

Why should you use ISO 1328‑2?

Spur gears are a toothed component with a cylindrical shape that is used in industrial machinery to convey mechanical motion and manage speed, power, and torque.

ISO 1328‑2 specifies the appropriate definitions of gear tooth deviations, the structure of the gear tooth flank classification system, and the allowable values of the gear tooth deviations.

ISO 1328‑2 provides formulae to calculate tolerances for individual product gears when mated in double flank contact with a master gear. 11 flank tolerance classes are defined, numbered 1 to 11, in order of increasing tolerance.

ISO 1328-2 specifies categorization tolerances and measuring procedures for unassembled gears.

ISO 1328-2 provides the gear manufacturer and the gear buyer with a mutually advantageous reference for uniform tolerances.

As a result, ISO 1328-2 will enable you to consistently manufacture or appropriately select high-quality, accurate gears for different industries that support optimal performance of applications.

What’s changed since the last update?

BS ISO 1328‑2:2020 supersedes BS 436‑5:1997, which is withdrawn. BS ISO 1328‑2:2020 includes some technical changes with respect to BS 436‑5:1997. These include:

The scope of applicability has been expanded to include sector gears
Revisions have been made to the formulae which define the double flank radial composite tolerances, and the range of classification numbers has been changed to clarify the independence of this classification system from that given in part 1
The change in tolerance value between consecutive tolerance classes has been reduced, so two steps in the new system result in the same change as one step of the old system, but approximately the same global range of tolerance values is maintained with additional steps
Evaluation of runout, previously handled in this document, has been moved to ISO 13281:2013
Advice on appropriate inspection methods has been removed; the information can be found in ISO/TR 100642

BS ISO 1328-2:2020

Cylindrical gears. ISO system of flank tolerance classification - Definitions and allowable values of double flank radial composite deviations

Current

Published:

31 Mar 2020