BS ISO 1328-2:2020 pdf free
BS ISO 1328-2:2020 pdf free.Cylindrical gears – ISO system of flank tolerance classification Part 2: Definitions and allowable values of double flank radial composite deviations.
4 Application of the ISO double flank radial composite tolerance classification system
4.1 General
This document provides classification tolerances and measuring methods for unassembled gears.Surface texture is not considered in this document. For additional information on surface texture, see ISO/TR 10064-4.
With agreement between the purchaser and manufacturer, the tolerances may be applied to other types of gears such as cylindrical worms, worm gears, racks, and bevel gears. However, in these cases, modified procedures and associated measurement processes should be considered since this standard only describes procedures for parallel axis gears. See lSO/TR 10Q642 for additional information.
Some design and application considerations may warrant measurements or documentation not normally included in standard manufacturing processes. Specific requirements shall be stated in the contractual documents.
Additional information on double flank testing is given in ISO/TR 10064-2.
NOTE 1 Tolerances for a specified class are calculated according to the formulae in Clause 5. To aid in visualizing how the tolerances change with the number of gear teeth, graphs are provided in Annex A showing tolerance values for 3 tolerance classes.
NOTE 2 There is no correlation or interrelation between the classes specified in this document and other parts or standards such as ISO 1328-1. This document uses a unique set of tolerance classes (i.e., R30 to R50) to reinforce that no correlation to other elemental or radial composite standards exists (see Annex C). However, while there is no general correlation to other standards, for a specific gear it is possible to find a tolerance class or classes according to this document that will give similar tolerances to those that were originally specified for the gear, see Annex D.
NOTE 3 The specific methods of measurement, documentation of the results, Inspection frequency, and use of statistical methods are items that normally are mutually agreed upon between the manufacturer and the purchaser.
4.2 Gear tooth tolerance class
In this document, the double flank radial composite tolerance class is determined by measurement of total radial composite deviation, Fid, and tooth-to-tooth radial composite deviation, fid. A gear that is specified to a single ISO double flank radial composite tolerance class shall meet both individual tolerance requirements.
In addition to the total and tooth-to-tooth tolerances, Annex B provides an optional specification for composite tolerance over a selected number of teeth, k.
NOTE 1 Specifying a class or measurement criteria that require more precise tolerances than required by the application can unnecessarily increase the cost.
NOTE 2 Double flank measurements, such as tight mesh center distance, can be used for control of tooth thickness and total radial composite effects simultaneously.
This document allows for the specification of separate classes for total radial composite deviation, Fid, and tooth-to-tooth radial composite deviation,f,d.BS ISO 1328-2 pdf download.
