AGMA 2011-A98

Abstract

This standard establishes a classification system which may be used to communicate geometrical accuracy specifications of unassembled cylindrical wormgearing with axes at right angles. It also provides information on measuring methods and practices. This standard provides the gear manufacturer and the gear purchaser with a mutually advantageous reference for uniform tolerances and inspection procedures. Tolerance grades 3 through 12 are defined in this standard and are based on the relative effect of geometrical errors on conjugate action for wormgear sets acting as speed reducers. <br> Tolerance equations and tables <br> Tolerance equations are provided in clause 5 for calculating the maximum values allowed by the specific tolerance grade. Tables are provided in annex A for reference. <br> Measuring methods and practices <br> Measuring methods and practices are included in order to promote uniform inspection procedures (see clause 4). These methods permit the manufacturer and purchaser to conduct measuring procedures which are accurate and repeatable to a degree compatible with the specified tolerance grade. <br> Exceptions <br> This standard applies to individual worm and gear components. It does not establish a tolerance grade for enclosed drive assemblies. Establishing ratings based on tolerance grade is beyond the scope of this standard. Gear design and backlash are also beyond the scope of this standard. Refer to the latest AGMA Publications Catalog for applicable standards. This standard does not apply to worms with mean diameters larger than 16 inches, nor does it apply to wormgears with mean diameters larger than 100 inches. This standard does not apply to geometry finer than 0.063 axial pitch. This standard does not apply to spiral gears or any type other than cylindrical single enveloping wormgearing. <br> Limitations <br> The American Gear Manufacturers Association makes no representation, warranty or guarantee in connection with the publication of any AGMA Standard and hereby expressly disclaims any liability or responsibility for loss or damage resulting from their use. Similarly, violation of any federal, state or municipal regulation with which an AGMA Standard may conflict, or for the infringement of any patent resulting from the use of an AGMA Standard is the responsibility of the user.