ABMA 3290:1998 pdf download.Rolling bearings – Balls – Dimensions and tolerances
1 Scope
This Intemational Standard specifies requirements for finished steel balls for rlling bearings.
2 Normative references
The following standards contain provisions, which through reference in this text, constitute provisions of this Intemational Standard. At the tirme of publication, the editions indicated were valid. All standards are subject o revision，and parties to agreements based on this Intermational Standard are encouraged切investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currenty valid International Standards. !ISO 4288:1996, Geormetrical Product 3pecifications (GPS)一Surface texture: Profile method 一Rules and procedures for the assessment of surface texture. ISO 4291:1985, Methods for the assessment of departure from roundness – – Measurement of variations in radius.
3 Definitions
For the purposes of this Intemational Standard the fllowing definitions apply. 3.1 nominal ball diameter, Dw: diameter value which is used for the general identification of a ball size. 3.2 single ball diameter, Dws: distance between two parallel planes tangential to the actual surface ofa ball. 3.3 mean ball diameter, Dwm: arthmetical mean of the largest and the smallest of the single diameters ofa ball., 3.4 vari tion ot ball diameter, Vom : difference between the largest and the smallest of the single diameters of a ball. 3.5 surface irregularities and form parameters: Various types of deviation from the pertect spherical ball surface, uniformly distributed and repeated around the ball surface. 3.5.1 deviation from sphericai orm: Greatest radial distance, in any eauatorial plane, between the smallest circumscribed sphere and the greatest inscribed sphere with their centre common to the least square sphere centre. NOTE一Information about the measurement of this deviation is given in annex B. 3.5.2 waviness: Surface irregularities of random or periodical deviation from the ideal spherical form. NOTE- It is recommended that waviness be evaluated as velocity ampitude. In practice, the waviness components are separated from the real surtace by a waviness analyser (iters). 3.5.3 surtace roughness: Surface irregularities with relatively small spacings, which usually include irregularties resulting from the method of manufacture being used and/or other influences. NOTE一These iregularties are considered within the limits which are conventionally defined, for example, within the limits of the sampling length. 3.6 ball lot: definite quantity of balls manutactured under conditions presumed unitform and which is considered as an entity. 3.7 mean diameter of ball lot, DwmL: arithmetical mean of the mean diameters of the largest ball and the smallest ball in a ball lot. 3.8 variation of ball lot diameter, Vowl: difference between the mean diameters of the largest ball and the smallest ball in a ball lot. 3.9 ball grade, G; specific combination of dimensional, fom, surface roughness and sorting tolerances for balls. NOTE- Ball grade in identified by the letter G and a number. 3.10 ball gauge, S: amount by which the mean diameter of ball iot should. differ from the nominal ball diameter, this amount being one of an established series. NOTES 1 Each ball gauge is a whole multiple of the ball gauge interval established for the ball grade in question (see also annex A). 2 A ball gauge, in combination with the ball grade and nominal diameter, should be considered as the most exact bal size specification to be used by a customer for ordering purposes. 3.11 deviation of ball lot from ball gauge, 0s: difference between the mean diameter of ball lot and the sum of the nominal ball diameter and the ball gauge (see also table 3 and annex A).
ABMA 3290:1998 pdf download
