part numbering part numbering system example ssri-418zzeea62ha5cxxp25l02p rif-1438fa7p13lg49u group 1 material group 2 type group 3 basic size group 4 seals sheilds group 5 modifications group 6 duplex pairs group 7 premium features group 8 cage ss ss=aisi stainless steel 440c no code=chrome alloy steel 52100 ce=chrome alloy steel rings 52100 with ceramic balls sb=440c modified se=aisi stainless steel rings 440c with ceramic balls st=aisi stainless steel rings 440c with tic coated balls xt=chrome alloy steel rings 52100 with tic balls ri rif 418 1438 inch series first one or two digits indicates o.d in 16ths of an inch the following two or three digits indicate the bore size in a fraction of an inch the first digit being the numerator and the second or the second and third digits being the denominator metric series first two digits indicate o.d in mm second two digits indicate i.d in mm x following basic size indicates special internal design assigned in numerical sequence i.e x1
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products inch metric and hi-speed specialty bearings inch series radial open unflanged 10 radial open flanged 11 radial shielded unflanged 12 radial shielded flanged 13 full complement radial open unflanged flanged 14 full complement radial shielded unflanged flanged 15 extended inner ring radial open unflanged flanged 16 extended inner ring radial shielded unflanged flanged 17 modified dimension radial open unflanged flanged 18 modified dimension radial shielded unflanged flanged .19-21 tapered o.d radial shielded flanged 22 hi-speed specialty bearings angular contact 23 radial .24-25 metric l series radial open unfla
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inch series full complement radial shielded unflanged flanged r r notes 1 inch to metric conversion see page 57 2 basic part numbers shown below include code ss for aisi 440c stainless steel if sae 52100 chrome alloy steel is desired delete ss 3 see page 7 for abec tolerances 4 r=maximum shaft or housing fillet radius that bearing corners will clear 5 add zz for two shields as a suffix to basic part number prior to letter f for flanged bearings substitute prefix ssrif or ssrf metric dimensions for reference only load ratings are based on abma standard #12 r lo d li d unflanged 2 shields df lo r d li d flanged 1 shield bf b b basic p/n inch bore d mm inch o.d d mm width b 2 shields inch mm flange dia df flange width bf land diameter reference li lo fillet radius r ball complement no z size db load ratings lbs dyn c static co nmaxlfn rpm/1000 ssri-2 1/2f ssri-3f ssri-4f ssri-3332f ssri-5f ssri-418f ssri-518f ssri-618f ssr-2f ssri-5532f ssri-5632f ssri-6632f ssr-3f ssri-614f ssr
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inch series modified dimension radial shielded unflanged flanged continued r r notes 1 inch to metric conversion see page 57 2 basic part numbers shown below include code ss for aisi 440c stainless steel if sae 52100 chrome alloy steel is desired delete ss 3 see page 7 for abec tolerances 4 r=maximum shaft or housing fillet radius that bearing corners will clear r lo d li d unflanged 2 shields ribbon cage df lo r d li d flanged 1 shield crown cage bf b b r ribbon or h crown cages are available as indicated please consult with factory for machined cage availability metric dimensions for reference only available only as flanged type load ratings are based on abma standard #12 basic p/n cage type bore d inch mm inch o.d d mm width b 1 shield inch mm flange flange 2 shields dia width inch mm df bf land diameter reference li lo ssri-8516zzsd502 r ssrif-8516zzsd502 r ssr-4zza01 r/h ssr-4zza12 r ssr-4zza63 r ssr-4zzsd548 ssr-4zzsd561 ssr-2270zzw301 ssri-8516zza02 ssr-2280zzw301 ssr
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metric l series radial shielded unflanged flanged r r notes 1 metric to inch conversion see page 57 2 basic part numbers shown below include code ss for aisi 440c stainless steel if sae 52100 chrome alloy steel is desired delete ss 3 see page 7 for abec tolerances 4 r=maximum shaft or housing fillet radius that bearing corners will clear 5 please consult with factory for cage availability 6 add z for single shield zz for two shields as a suffix to basic part number prior to y or w width variations available only as flanged type production standard for flange bearing substitute prefix sslf when applicable inch conversion given for reference only load ratings are based on abma standard #12 r lo d li d unflanged 1 shield df lo r d li d flanged 2 shields bf b b land diameter reference li lo basic p/n mm bore d inch mm o.d d inch width b mm flange flange dia width inch df bf fillet radius r mm inch ball complement no z size db load ratings lbs dyn c static co nmaxlfn rpm/1000
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engineering cages the most common bearing cages are shown below in some cases such as high-load applications a full complement design may be the best choice for operating speed please refer to the nmax/fn values in the product tables and the multiplier table on page 39 nhbb can also supply specially designed cages to meet your specific requirements if any doubt nhbb should be contacted for optimum cage selection basic cage capabilities description ribbon two-piece stamped crimped r design material a.i.s.i 305 steel max speed ref dn 150,000 operating temp max 900°f comments superior starting torque low cost typical applications general purpose crown one-piece stamped h a.i.s.i 410 steel 150,000 -900°f higher speed capability than ribbon retainer low cost high speed impregnated with oil general purpose crown one-piece machined kb kc phenolic-paper base phenolic-linen base polyamide-imide 1,200,000 250°f medical machine tools high speed motors medical/dental high temperature full type
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engineering lubrication lubrication methods centrifuging an oil-lubricated bearing removes excess oil and leaves only a very thin film on all surfaces this method is used on very low torque bearings and can be specified for critical applications vacuum impregnation used with ball bearings containing porous cages forces lubricant into the pores using the cage as an oil reservoir when this method is used with a greased bearing its purpose is to prevent the cage material from leaching oil from the lubricant normally the base oil of the grease is used in the cage to prevent incompatibility grease packing approximately 1/4 to 1/3 of a ball bearing s internal free volume is one of the most common methods of lubrication grease quantity can be controlled by the use of special lubrication equipment grease plating consists of mixing a quantity of grease and solvent to the desired consistency lubricating the bearing with this mixture then evaporating the solvent at a moderate temperature leaving
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engineering load ratings and bearing life calculation of fatigue life while miniature and instrument bearings may fail from causes other than fatigue the fatigue life should be calculated to ensure against failure to calculate fatigue life follow the procedure in the table below fatigue life pounds and inches step given radial load thrust load speed obtain lubricant viscosity consult with factory select bearing read dynamic load rating read static load rating read ball size select radial play range obtain initial contact angle using db and table obtain t1 from t1 nomograph using co t and o above obtain r1 from r1 nomograph using o above obtain pe where pe t1 r1 or pe r whichever is greater obtain lb10 from b10 life nomograph number of revolutions or hours using c and pe above obtain lubricant life modifier from lubricant effect nomograph using c t r v and n above obtain reliability life modifier a2 from the table for lb10 obtain design life l where l a1 a2 lb10 item/operation symb
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engineering mounting and coding design of mating equipment a bearing which is fitted too tightly or too loosely or is damaged during assembly due to excessive force or shock loading may cause your device to perform in a substandard manner this possibility can be greatly reduced by following some general guidelines during the design of mating parts see table of recommended fits on page 53 and by observing the following four cautions during the assembly process caution 1 when establishing shaft or housing sizes the effect of differential thermal expansion must be accounted for if thermal gradients are present or dissimilar materials are used room temperature fits must be adjusted accordingly approximate thermal coefficients for common materials are available from nhbb caution 2 when miniature and instrument bearings are interference fitted either intentionally or as a result of thermal gradients the bearing radial play is reduced by an amount equal to approximately 80 of the actual diam
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engineering metric conversion table fraction 1/64 1/32 inch 0.0156 0.0250 0.0312 0.0394 0.0400 3/64 0.0469 0.0472 0.0550 0.0591 1/16 5/64 0.0625 0.0709 0.0781 0.0787 0.0906 3/32 0.0937 0.0984 0.1000 0.0124 7/64 0.1094 0.1100 0.1102 0.1181 1/8 0.1250 0.1256 0.1378 9/64 5/32 11/64 3/16 0.1406 0.1562 0.1575 0.1719 0.1875 0.1892 0.1969 13/64 7/32 15/64 1/4 17/64 9/32 19/64 0.2031 0.2165 0.2187 0.2344 0.2362 0.2500 0.2656 0.2756 0.2812 0.2883 0.2969 mm 0.3969 0.6350 0.7937 1.0000 1.0160 1.1906 1.2000 1.3970 1.5000 1.5875 1.8000 1.9844 2.0000 2.3012 2.3812 2.5000 2.5400 2.6000 2.7781 2.7940 2.8000 3.0000 3.1750 3.1902 3.5000 3.5719 3.9687 4.0000 4.3656 4.7625 4.8057 5.0000 5.1594 5.4991 5.5562 5.9531 6.0000 6.3500 6.7469 7.0000 7.1437 7.3228 7.5406 43/64 11/16 45/64 21/32 41/64 19/32 39/64 5/8 9/16 37/64 33/64 17/32 35/64 31/64 1/2 15/32 7/16 29/64 27/64 13/32 23/64 3/8 25/64 21/64 11/32 fraction 5/16 inch 0.3125 0.3150 0.3281 0.3437 0.3543 0.3594 0.3750 0.3906 0.3937 0.4062 0.4100 0.4219 0.
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nhbb precision division corporate headquarters 9700 independence avenue chatsworth california 91311 hitech division 175 jaffrey road peterborough new hampshire 03458 astro division 155 lexington drive laconia new hampshire 03246 tel 603 924-4100 east fax 603 924-9302 east 818 993-4100 west 818 407-5020 west nhbb europe 1 sterling centre eastern road bracknell berkshire rg12 2pw england tel 44 0 1344-308888 fax 44 0 1344-307777 visit us at www.nhbb.com © 2002 nhbb inc.
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