Applicable standard Tolerance class Tolerance table. class 0. class 0. ANSI/ABMA Std.19. ANSI/ABMA Std class 0 class 6 class 5 class 4 class 2

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1 . Bearing Tolerances. Dimensional accuracy and running accuracy Bearing tolerances or dimensional accuracy and running accuracy, are regulated by ISO and JIS B standards (rolling bearing tolerances). For dimensional accuracy, these standards prescribe the tolerances necessary when installing bearings on shafts or in housings. Running accuracy is defined as the allowable limits for bearing runout during operation. Dimensional accuracy Dimensional accuracy constitutes the acceptable values for bore diameter, outer diameter, assembled bearing width, and bore diameter uniformity as seen in chamfer dimensions, allowable inner ring tapered bore deviation and shape error. Also included are, average bore diameter variation, outer diameter variation, average outer diameter unevenness, as well as raceway width and height variation (for thrust bearings). Running accuracy Running accuracy constitutes the acceptable values for inner and outer ring radial runout and axial runout, inner ring side runout, and outer ring outer diameter runout. Allowable rolling bearing tolerances have been established according to precision es. Bearing precision is stipulated as JIS,,, or, with precision rising from ordinary precision indicated by. Table. indicates which standards and precision es are applicable to the major bearing types. Table. shows a relative comparison between JIS B precision standards and other standards. For greater detail on allowable limitations and values, refer to Tables. -.. Allowable values for chamfer dimensions are shown in Table.9, and allowable limitations and values for radial bearing inner ring tapered bores are shown in Table.. Table. Bearing types and applicable tolerance Bearing type Deep groove ball bearings Angular contact ball bearings Self-aligning ball bearings Cylindrical roller bearigns Needle roller bearings Spherical roller bearings Tapered roller bearings metric Thrust ball bearings Inch J series Spherical roller thrust bearings Applicable standard Tolerance Tolerance table JIS B (ISO9) Table. JIS B X Table. ANSI/ABMA Std.9 Table. ANSI/ABMA Std.9. K N C B A Table. JIS B Table. (ISO99) Table. Table. Comparison of tolerance ifications of national standards Standard Japanese industrial standard (JIS) International Organization for Standardization (ISO) Deutsches Institut fur Normung(DIN) Applicable standerd JIS B ISO 9 ISO 99 ISO ISO DIN American National Standards Institute (ANSI) ANSI/ABMA Std. American Bearing Manufacturer's Association ANSI/ABMA Std.9. (ABMA) ANSI/ABMA Std.9 Tolerance Class Class,X Class Class Class Class Normal Class X Class Class Class Class Normal Class Class Class Class Class Class Class Class Class A Class A P P P P P ABEC- RBEC- Class K Class ABEC- RBEC- Class N Class ABEC- RBEC- ABEC- ABEC-9 Class C Class B Class A Class Class Class "ABEC" is applied for ball bearings and "RBEC" for roller bearings. Notes : JIS B, ISO 9 and 99, and DIN have the same specification level. : The tolerance and allowance of JIS B are a little different from those of ABMA standards. All type Bearing Types Radial bearings Thrust ball bearings Tapered roller bearings (Inch series) Precision instrument bearings All type Radial bearings (Except tapered roller bearings) Tapered roller bearings (Metric series) Tapered roller bearings (Inch series) A-

2 Table. Tolerance of radial bearings (Except tapered roller bearings) Table. () Inner rings Nominal bore diameter d over incl.... Dimensional tolerance of mean bore diameter within plane Δdmp high low high low high low high low high low diameter series 9 Bore diameter variation Vdp diameter series. The dimensional difference Δds of bore diameter to applied for and is the same as the tolerance of dimentional difference Δdmp of average bore diameter. However, the dimensional difference is applied to diameter series,,, and against Class, and to all the diameter series against Class diameter series Table. () Outer rings Nominal outside diameter D over incl.. Dimensional tolerance of mean outside diameter within plane ΔDmp high low high low high low high low high low diameter series 9 Outside diameter variation VDp open type diameter series. diameter series.. The dimensional difference ΔDs of outer diameter to be applied for es and is the same as the tolerance of dimensional difference ΔDmp of average outer diameter. However, the dimensional difference is applied to diameter series,,, and against Class, and also to all the diameter series against Class A-

3 Mean bore diameter variation Vdmp Inner ring radial runout Kia Side runout with bore Sd Inner ring axial runout 9 9 Applies to ball bearings such as deep groove ball bearings and angular ball bearings. To be applied for individual raceway rings manufactured for combined bearing use. Nominal bore diameter of bearings of. is included in this dimensional division Inner ring width deviation ΔBs Sia normal,, high low high low high low modified,, high low high low Unitm Inner ring width variation VBs Unit m Outside diameter variation VDP Sealed/shield bearings diameter series,,,,,, 9 9 Mean bore diameter variation VDmp Outer ring radial runout 9 To be applied in case snap rings are not installed on the bearings. Applies to ball bearings such as deep groove ball bearings and angular ball bearings. Nominal outer diameter of bearings of. is included in this dimensional division. 9 Kea.... A- Outside surface inclination 9 SD Outside ring axial runout Sea.... Outer ring width deviation ΔCs all type Depends on tolerance of ΔBs in relation to d of same bearing Outer ring width variation, Depends on tolerance of VBs in relation to d of same bearing VCs

4 Table. Tolerance of tapered roller bearings (Metric series) Table. () Inner rings Nominal bore diameter d over incl. Dimensional tolerance of mean bore diameter within plane Δdmp,X, high low high low high low ,X Bore diameter variation Vdp, The dimensional difference Δds of bore diameter to be applied for is the same as the tolerance of dimensional difference Δdmp of average bore diameter. 9 Mean bore diameter variation,x Vdmp 9 9 Inner ring radial runout,x Kia Side runout with bore Sd 9 Table. () Outer rings Nominal outside diameter D over incl. Dimensional tolerance of mean outside diameter within plane ΔDmp,X, high low high low high low ,X Outside diameter variation VDp 9 Does not apply to bearings with flange. The dimensional difference ΔDs of outside diameter to be applied for is the same as the tolerance of dimensional difference ΔDmp of average outside diameter. 9 Mean bore diameter variation,x 9 9 VDmp Outer ring radial runout,x 9 Kea Outside surface inclination SD 9 A-

5 Unitm Inner ring axial runout Sia Inner ring width deviation ΔBs Assembly width deviation of single-row tapered roller bearings ΔTs Combination width deviation of double row bearings ΔBs, ΔCs Combination width deviation of -row bearings ΔBs,ΔCs, X, high low high low high low, X, high low high low high low,, high low,, high low Outer ring axial runout Sea Outer ring width deviation Depends on tolerance of ΔBs in relation to d of same bearing ΔCs Unitm,,, X high low high low Applies to bearing where d is greater than but is less than or equal to. Table. () Effective width of outer and inner rings with roller Nominal bore diameter d over T incl. Effective width deviation of roller and inner ring assembly of tapered roller bearing ΔTs X high low high low Master cup sub-unit T Unitm Tapered roller bearing outer ring effective width deviation ΔTs X high low high low Master cone sub-unit d d A-9

6 Table. Tolerance of tapered roller bearings (Inch series) Table. () Inner rings Unitm Nominal bore diameter Single bore diameter deviation d Δds (inch) Class Class Class Class Class over incl. high low high low high low high low high low.( ) ( ).(.) (.).( ) ( ) 9.( ) ( ) 9.( ) ( ) 9.( ) ( ) + + Table. () Outer rings Unitm Nominal outside diameter Single outside diameter deviation D ΔD (inch) Class Class Class Class Class over incl. high low high low high low high low high low.(.) (.).( ) ( ) 9.( ) ( ) 9.( ) ( ) 9.( ) ( ) + + Table. () Single-row tapered roller bearing assembly width, combination width of -row bearings, effective width of inner ring with rollers, effective width of outer ring Nominal Nominal Overall width deviation of assembled single row tapered roller bearing Overall width deviation bore outside of assembled ΔTs diameter -row diameter tapered roller bearings d D ΔBs, ΔCs (inch) (inch) Class Class Class Class, Class,,, over incl. over incl. high low high low high low high low. ( ) ( ). () () 9. (). () + -. () 9. () 9. (). () Table. () Radial deflection of inner and outer rings Nominal outside diameter D (inch) over. () 9. () 9. () incl.. () 9. () 9. () Class Class low - - Inner ring radial runout Kia Outer ring radial runout Kea Class A- high Class Unitm Class

7 T Master cup sub-unit T Master cone sub-unit d d Effective width deviation of roller and inner ring assembly of tapered roller bearing ΔTs Class Class Class high low high low high low To be applied for nominal bore diameters d of. ( inch) or less. Unitm Tapered roller bearing outer ring effective width deviation ΔTs Class Class Class high low high low high low A-

8 Table. Tolerance of tapered roller bearings of J series (Metric series) Table. () Inner rings Nominal Mean bore diameter deviation Bore diameter variation Mean bore diameter bore diameter Vdp variation Δdmp d Vdmp Class Class Class Class Class Class Class Class Class Class Class Class K N C B K N C B K N C B over incl. high low high low high low high low Note: Please consult NTN Engineering for Class A bearings Table. () Outer rings Nominal Mean outside diameter deviation Outside diameter outside variation ΔDmp diameter VDp D Class Class Class Class Class Class Class Class K N C B K N C B over incl. high low high low high low high low Mean outside outer ring diameter variation axial runout VDmp Sea Class Class Class Class Class K N C B B Note: Please consult NTN Engineering for Class A bearings. Table. () Effective width of inner and outer rings Unitm Nominal Effective width deviation of roller and inner ring Tapered roller bearing outer ring bore diameter assembly of tapered roller bearing effective width deviation ΔTs d ΔTs Class Class Class Class Class Class Class Class K N C B K N C B over incl. high low high low high low high low high low high low high low high low Note : " " mark are to be manufactured only for combined bearings. : Please consult NTN Engineering for Class A bearings. A-

9 Unitm Inner ring Overall width deviation of assembled axial runout tapered roller bearing ΔTs Sia Class B Class K Class N Class C Class B sup inf sup inf sup inf sup inf Table. () Radial runout of inner and outer rings Nominal outside diameter D over incl. Unitm Inner ring radial runoutkia and Outer ring radial runoutkea Class Class Class Class K N C B Note: Please consult NTN Engineering for Class A bearings. T Master cup sub-unit T Master cone sub-unit d d A-

10 Table. Tolerance of thrust ball bearings Table. () Shaft raceway washer Unitm over Nominal bore diameter d incl. Mean bore diameter deviation Class,, Δdmp Class high low high low Bore diameter variation Class,, Vdp Class Class Raceway thickness variation Class Si Class Class Table. () Housing raceway washer Unitm Nominal outside diameter D over incl. Mean outside diameter deviation Class,, ΔDmp Class high low high low Outside diameter variation Class,, VDp Class Class Raceway thickness variation Se Class Class Class According to the tolerance of S against "d" of the same bearings Table. () Bearing height Unitm Nominal bore diameter d Single direction Bearing height deviation ΔTs over incl. high low This standard is applied for flat back face bearing of. A-

11 Table. Tolerance of spherical thrust roller bearing Table. () Shaft raceway washer Nominal bore diameter d Mean bore Bore Side diameter deviation diameter runout variation with bore Δdmp Unitm Bearing height deviation over incl. high low high low Table. () Housing raceway washer Unitm Nominal Single plane mean outside diameter outside diameter D deviation ΔDmp over incl. high low Vdp Sd ΔTs , - - A-

12 . Chamfer measurements and tolerance or allowable values of tapered bore Side face of inner ring or center washer, or side face of outer ring Table.9 Allowable critical-value of bearing chamfer Table.9 () Radial bearing (Except tapered roller bearing) Unit rs min or rs min Nominal bore diameter d over incl. Radial direction rs orrs Axial direction rs min or rs min Bore diameter face rs min or rs min of bearing or outer diameter face of rs or rs bearing (Axial direction) Table.9 () Tapered roller bearings of metric series rs min or rs min or rs min rs min rs or rs (Radial direction) Nominal bore diameter of bearing "d" or nominal outside diameter "D" over incl. Radial direction rs orrs Axial direction Unit These are the allowable minimum dimensions of the chamfer dimension "r" or "r" and are described in the dimensional table These are the allowable minimum dimensions of the chamfer dimension "r" or "r" and are described in the dimensional table. Inner rings shall be in accordance with the division of "d" and outer rings with that of "D". Note: This standard will be applied to the bearings whose dimensional series (refer to the dimensional table) are specified in the standard of ISO or JIS B. For further information concerning bearings outside of these standards or tapered roller bearings using US customary unit, please contact NTN Engineering. A-

13 ΔdΔd d d d+δd d+δd B Theoretical tapered bore B Tapered bore having dimensional difference of the average bore diameter within the flat surface Table.9 () Thrust bearings rs min orr min rs orrs Radial and axial direcition These are the allowable minimum dimensions of the chamfer dimension "r" or "r" and are described in the dimensional table. Unit Table. () Tolerance of and tolerance values for tapered bore of radial bearings Standard taper ratio : tapared hole ( ) Unitm d Δdmp Vdp Δdmp - Δdmp over incl. high low high low ,,,,, Table. () Tolerance of and tolerance values for tapered bore of radial bearings Standard taper ratio : tapered bore ( ) Units m d Δdmp Δdmp Δdmp Vdp over incl. high low high low Applies to all radial flat planes of inner ring tapered bore. Does not apply to diameter series and. Note: Quantifiers For a standard taper ratio of :ddb For a standard taper ratio of :ddb Δdmp Dimensional difference of the average bore diameter within the flat surface at the theoretical small end of the tapered bore. ΔdmpDimensional difference of the average bore diameter within the flat surface at the theoretical large end of the tapered bore. VdpUnevenness of the bore diameter with the flat surface BNominal width of inner ring Half of the tapered bore s nominal taper angle For a standard taper ratio of :9. For a standard taper ratio of :. A-

14 . Bearing tolerance measurement methods For reference, measurement methods for rolling bearing tolerances are in JIS B. Table. shows some of the major methods of measuring rotation tolerances. Table. Rotation tolerance measurement methods Characteristic tolerance Measurement method Inner ring radial runout (Kia) Radial runout of the inner ring is the difference between the imum and minimum reading of the measuring device when the inner ring is turned one revolution. Outer ring radial runout (Kea) Radial runout of the outer ring is the difference between the imum and minimum reading of the measuring device when the outer ring is turned one revolution. Inner ring axial runout (Sia) Axial runout of the inner ring is the difference between the imum and minimum reading of the measuring device when the inner ring is turned one revolution. Outer ring axial runout (Sea) Axial runout of the outer ring is the difference between the imum and minimum reading of the measuring device when the outer ring is turned one revolution. Inner ring side runout with bore (Sd) Inner ring side runout with bore is the difference between the imum and minimum reading of the measuring device when the inner ring is turned one revolution together with the tapered mandrel. Outer ring outside surface inclination (SD).rs.rs Reinforcing plate Outer ring outside surface inclination is the difference between the imum and minimum reading of the measuring device when the outside ring is turned one revolution along the reinforcing plate. A-