ABMA 3096:2014 pdf download.Rolling bearings – Needle rollers – Dimensions and tolerances
1 Scope
This International Standard specifies dimensions and tolerances for finished steel needle rollers used as rolling elements.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IS0 286-2 :I 988, IS0 system of limits and fits – Part 2: Tables of standard tolerance grades and limit deviations for holes and shafts. IS0 4291 :1985, Methods for the assessment of departure from roundness – Measurement of variations in radius.
3 Terms, definitions and symbols
For the purposes of this International Standard, the following terms and definitions apply. The symbols (except those for tolerances) shown in figures 1 and 2 and the values given in tables 1 and 3 denote nominal dimensions unless specified otherwise. 3.1 nominal diameter of a needle roller, Dw: Diameter value used for the purpose of general identification of a needle roller diameter. See figures 1 and 2. 3.2 single diameter of a needle roller, D,, :Distance between two tangents to the needle roller surface parallel to each other and in a plane perpendicular to the needle roller axis, i.e. a radial plane. 3.3 mean diameter of a needle roller in a single plane, Dwmp: Arithmetical mean of the largest and the smallest actual single diameters of the needle roller in a single radial plane. 3.4 nominal length of a needle roller, I+,,: Length value used for the purpose of general identification of a needle roller length. See figures 1 and 2.3.5 single length of a needle roller, IL,,,, s : Distance between the two radial planes which just contain the end extremities of the needle roller. 3.6 single chamfer dimension (of flat end needle roller), rs. See figure 1. 3.7 smallest permissible single chamfer dimension (of flat end needle roller), rs min. 3.6 largest permissible single chamfer dimension (of flat end needle roller), r, max. 3.9 profile at the ends of rounded end needle rollers, R: Profile which may not necessarily be a true radius but shall fall within the limits of &/2 and LJ2. 3.10 circularity deviation: Difference between the largest radius and the smallest radius of the measured profile of the workpiece, the values of the radii being taken from the centre of the least squares mean circle, LSC. 3.11 needle roller gauge: Diameter deviation range limited by a high and a low deviation of the mean needle roller diameter Dwmp from the nominal diameter, D,, in a radial plane through the middle of the roller length. NOTE- A gauge is designated by the high and low deviation expressed in micrometres, for example -2 -4. 3.12 gauge lot: Quantity of needle rollers, of the same grade and nominal dimensions, all having a mean diameter Dwmp within the same gauge. NOTE- Needle rollers of any grade and nominal dimensions are supplied in gauge lots. If nothing to the contrary has been agreed between the customer and the supplier, the gauge lots may be of any one or more of the gauges included in table 2. 3.13 variation of gauge lot diameter, VD,,,,L: Difference between the mean diameter Dwmp of the needle roller having the largest mean diameter and that of the needle roller having the smallest mean diameter in the gauge lot. 3.14 needle roller grade: Specific combination of diameter and form tolerances for a needle roller, characteristic of its level of accuracy. NOTE -A needle roller grade is designated by a number.
ABMA 3096:2014 pdf download
