ABMA 20:1996 pdf free

ABMA 20:1996 pdf free.RADIAL BEARINGS OF BALL,CYLINDRICAL ROLLER AND SPHERICAL ROLLER TYPES,METRIC DESIGN
Bearing manufacturers should select from the basic plan those sizes and proportions that are suitable for the bearing types and applications under consideration. Bearing users should select bearings from manufacturers’ specifications,giving preference to those bearings whose dimensions conform to the basic plan.
Another object of this plan is to achieve the benefits of international standardization of bearing dimensions. This has been accomplished due to the fact that this plan was developed in cooperation with the International Organization for Standardization (ISO) and generally conforms to those standards adopted by ISO. Differences from ISO standards are noted in the text or tables of this standard.
Metric bearings of dimensions conforming to the plan are manufactured in plants using the metric system of measurement and also in plants using the inch system of measurement. When the inch system is used, the basic metric boundary dimensions are converted to equivalent inch dimensions in accordance with ANSIEEE 268 carried to four decimal places.
The metric dimensions and their equivalent inch dimensions differ by 0.00005 inch or less (except for width in radial dimensions series 32,92, 33, and 93), an amount that is too small to be of practical significance. Therefore bearings made to either system of measurement are equally acceptable as being in accord with this standard.
Most ball and cylindrical roller bearings,manufactured in USA to the radial dimension series 32, 92, 33, and 93 have fractional inch
width dimensions. When converting these to millimeters carried to one decimal place, the resulting discrepancy is 0.05 mm (0.002 inch) or less which in this case is too small to be of practical significance.
In addition to those dimensions identified that differ from those in IO standards, this standard contains chamfer dimensions and radial internal clearance limits for a radial cylindrical roller bearing which has bore and outside diameter dimensions conforming to the Basic Plan for Boundary Dimensions given in Table 1, but has an extra large chamfer on one side and a broken small corner on the other side (see Tables 18 and 21).ABMA 20 pdf free download.