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Inner Rings (with 4-digit number for drawn cup bearings only)
Suffixes: limited availabilityF plastic cage
GF grease fitting, closed endOH oil hole
OHE oil hole in closed end
Drawn Cup Bearings – Inch Nominal DimensionsPrefixesB full complement of mechanically
retained needle rollersG extraprecisionH heavy seriesJ cage
M closed endT one seal
TT two seals
356
358
Full Complement Full ComplementMechanically Retained Rollers Closed End
INTRODUCTION
Before selecting individual bearings the Engineering section of thiscatalog should be reviewed for detailed information concerning:
• bearing type selection • example of life calculation
• bearing life and reliability • lubrication
• definition of load ratings • limiting speeds
• life and load relationships • shaft design
• effect of raceway hardness • housing design
In addition to these general considerations, review the materialwhich follows when selecting drawn cup bearings.
IDENTIFICATION
The prefix letter or letters in the bearing designation for Drawn Cup(DC) bearings denote whether the bearings are made to inch or metricnominal dimensions as well as their major construction features.
For example, a bearing with metric nominal dimensions isindicated by the code letter F or HK having open ends and letters BKfor closed ends, in the prefix. Letters in the prefix other than HK, BKor F indicate a bearing of inch nominal dimensions.
Most sizes of inch bearings are available with either a fullcomplement of rollers or caged rollers. Metric bearings are availablewith caged rollers as a standard. The use of caged rollers in inchbearings is indicated by the prefix code letter J.
Inch bearings are available in either of two radial cross sections.The larger cross section is indicated by the prefix code letter H.Absence of the letter H indicates the smaller radial cross section.
These major features of dimension and construction are summa-rized in Table 1.
In addition, there can be other identifying letters which coverspecial modifications. Please consult Torrington Engineering SalesOffice when special modifications are required.
Table 1
Identifying Letters
Prefix Letters in Bearing Designation
Inch Series Metric Series
Smaller Larger Regular
Roller Roller Roller
Full Complement B BH —
Mechanically Retained
Caged J JH HK,FJ
Other prefix letters in inch bearings denoting major constructionfeatures are:
M – closed end styleP – open end (finger) cageT – single seal
TT – double sealG – extra-precision
Since the entire identification code in the bearing designation maynot appear on the bearing itself, the manufacturers’ parts list oranother reliable source should always be consulted when orderingbearings for service or field replacement to make certain that thecorrect bearing with the correct lubricant is used.
BORE/O.D. COMPARISON,STANDARD AND LARGER ROLLERS
As noted above, many sizes of Torrington inch drawn cup needleroller bearings are made in two bore/o.d. series, differing primarily inthe roller diameter for a given bearing bore. Both series are verycompact and offer very low cross section profiles compared with otherrolling bearing types. The more compact series with the smaller rollersoffers optimum performance with minimum feasible outside diameterfor a given shaft size. The series with larger rollers, designated by theletter prefix H, offers more capacity and better performance at higherspeeds for the same given shaft size.
Full Complement Bearings
DRAWN CUP NEEDLE ROLLER BEARINGS
359
C A G E R O TAT ION
S H A F T R O TAT ION
ROLLER ROTATION
AMPLELUBRICANTSTORAGE
ROLLER ROTATIONDISTRIBUTES LUBRICANT
TO ALL CONTACT SURFACES
FULL COMPLEMENT BEARING CONSTRUCTIONThe original drawn cup needle roller bearing, as invented andintroduced by Torrington, employs a full complement of rollers. Thefull complement drawn cup bearing combines maximum capacityand low cost with the advantages of the drawn outer ring.
The inward turned lips of the cup are used to mechanically retainthe full complement of needle rollers to provide positive radialretention of the rollers even though it may be necessary to removethe shaft repeatedly during the servicing of the mechanismemploying the bearing.
CAGED BEARING CONSTRUCTIONTorrington caged drawn cup bearings have a steel cage whichprovides inward retention of the needle rollers. The design providesmaximum cage strength consistent with the long life requirements.
Torrington also has available bearings with other cage designs.Bearings with reinforced plastic cages are for use where operatingconditions permit. Before applying bearings with plastic cagesplease consult Torrington sales or engineering personnel.
SEALED BEARINGSTorrington drawn cup caged needle roller bearings are offeredwith integral seals. The tables of dimensions on pages 378-379indicate those sizes available with lip contact seals which limit thebearing operating temperature between -25°F and +225°F (-30°Cand +110°C). The seal lip design achieves a light and constantcontact with the shaft throughout the range of mounting bearingclearances thereby ensuring positive sealing and low frictional drag.
Sealed drawn cup bearings are intended to retain grease or non-pressurized oil within a bearing while also preventing contaminantsentering the raceway area. These seals are not intended towithstand a pressure differential exceeding 2 psi (14kPa).
Details of shaft design for sealed bearings are given in theEngineering section of this catalog.
The standard lip contact seals are compatible with commonlubricating oils and petroleum based fuels, but they are adverselyaffected by certain fire-resistant hydraulic fluids and most commonsolvents.
If the operating temperature must be outside of the above rangeor if seals are exposed to unusual fluids please consult theTorrington Engineering Sales Office.
Full Complement Full ComplementMechanically Retained Rollers Closed End
Caged, Caged,Cage Retained Rollers Closed End
Caged BearingConstruction
Caged,Double Sealed
DRAWN CUP NEEDLE ROLLER BEARINGS
360
DESCRIPTION OF TABULAR DATAThe opportunities for interchange of different types and series areseen in the tables of dimensions starting on page 364, wherebearings with the same bore, o.d. and width are listed on the sameline in the table. (Sealed DC bearings are shown on pages 378-379and extraprecision DC bearings are shown on pages 376-377.)
INTERNAL CLEARANCES AND FITSDrawn cup bearings are manufactured to a degree of precision thatwill satisfy the radial clearance requirements of most applications.The total radial clearance of an installed DC bearing results from thebuild-up of manufacturing tolerances of the housing bore, innerraceway o.d. and the bearing, as well as the minimum radialclearance required for the application.
For bearings of nominal inch dimensions, the recommendedmounting dimensions will provide correct running clearance for mostapplications. Closer control of radial clearance would be governed bythe user’s capability of holding housing and shaft raceway dimen-sional tolerances tighter than the limits shown on the tabular pages.
For bearings of nominal metric dimensions, the recommendedmounting dimensions shown on the tabular pages are consistent withISO N7 housing bore and h6 inner raceway o.d. tolerances. Whencloser control of clearance is required, the user may select N6housing bore and h5 inner raceway o.d. tolerances.
The drawing illustrates the manufacturing tolerances and thebuilt-in clearances applying to medium size drawn cup bearings inrotating applications when using the recommended tabulatedmounting dimensions.
Radial clearance in a mounted bearing may be more closelycontrolled by reducing the manufacturing tolerances of the housingbore and inner raceway diameter. Where extremely close control ofradial clearance is required for bearings of nominal inch dimensions,extraprecision full complement bearings are available.
OUTER RING ROTATIONFor applications where the outer ring rotates with respect to the load,it is recommended that both the housing bore and the inner racewaydiameter be reduced.
Bearings of nominal inch dimensions should have the housingbore and inner raceway diameter reduced by .0005" or .013 mm.
Bearings of nominal metric dimensions should follow ISO R7 andf6 tolerance practices.
OSCILLATING MOTIONApplications involving oscillating motion often require reduced radialclearances. This reduction is accomplished by increasing the shaftraceway diameters as shown in Tables 2 and 3. The metric bearinguser should note that addition of these values to the h6 tolerancesgiven in tables of dimensions results in a standard j6 tolerance.
Table 2Nominal inch bearing oscillating shaft size
shaft size add
inch mm inch mm
3⁄32 to 3⁄16 incl 2.38 to 4.76 incl 0.0003 0.0081⁄4 to 1 7⁄8 incl 6.35 to 47.62 incl 0.0005 0.013
INSTALLATION PROCEDURESA drawn cup bearing must be pressed into its housing. An installa-tion tool similar to the one illustrated must be used in conjunctionwith a standard press.
It is advisable to utilize a positive stop on the press tool to locatethe bearing properly in the housing. The assembly tool should havea leader or pilot, as shown, to aid in starting the bearing true in thehousing.
The installation tool must be coaxial with the housing bore. Theball detent shown on the drawing is used to assist in aligning therollers of a full complement bearing during installation and to holdthe bearing on the installation tool.
Assemble the bearing with the stamped end (the end withidentification markings) against the angled shoulder of the pressingtool.
Never hammer the bearing into its housing even in conjunctionwith the proper assembly mandrel.
Never press the bearing tightly against a shoulder in the housing.If it is necessary to use a shouldered housing, the depth of thehousing bore must be sufficient to ensure the housing shoulder fillet,as well as the shoulder face, clears the bearing.
To remove a drawn cup bearing from a through-bored housing,use a tool similar to the installation tool illustrated, but without thestop. For suggested methods of removing bearings from blind andshouldered bores, consult the Torrington Engineering Sales Officepersonnel.
A– 1⁄64" (0.4 mm) less than housing boreB– .003" (0.08 mm) less than shaft diameterC– distance bearing will be inset into housing, minimum of
.008" (0.2 mm)D– pilot length should be length of bearing less 1⁄32" (0.8 mm)E– approximately 1⁄2 D
362
INNER RINGSWhere it becomes impractical to meet the shaft raceway design
requirements (hardness, case depth, surface finish, etc.) outlined inthe General Engineering section, standard inner rings for drawn cupbearings are available. These are tabulated on pages 380 to 383 ofthe drawn cup section.
Inner rings for drawn cup bearings are designed to be a loosetransition fit on the shaft and should be clamped against a shoulder.
If a tight transition fit must be used to keep the inner ring fromrotating relative to the shaft, the inner ring o.d., as mounted, mustnot exceed the raceway diameters required by the drawn cup bearingfor the particular application. See the previous discussion on internalclearances and fits for further details on inner raceway diameterchoice.
LUBRICATIONDrawn cup bearings can be furnished with an oil hole (centered in
the drawn cup) to facilitate relubrication. If desired, specify on order.For general information regarding lubrication of drawn cup
bearings refer to page E72.
INSPECTION PROCEDURESAlthough the bearing cup (outer ring) is accurately drawn from
strip steel it may go out of round during heat treatment. When thebearing is pressed into a true round housing or ring gauge of correctsize and wall thickness, it becomes round and is sized properly. Forthis reason, it is incorrect to inspect an unmounted drawn cupbearing by measuring the o.d. The correct method for inspectingthe bearing size is to:
(1) press the bearing into a ring gauge of proper size.(2) plug the bearing bore with the appropriate “go” and “no go”
gauges.Tables 4 and 5 provide the correct ring and plug gauge diameters
for inspecting Torrington drawn cup needle roller bearings. When theletter H appears in the inch series bearings column headed “nominalbore diameter,” the gauge sizes listed are for the larger cross sectioninch series bearings which include H in their bearing designationprefix.
Example 1Find the ring gauge and plug gauge dimensions for a BH-68
bearing.Since the bearing designation prefix does not include the letter
SF or HK, this bearing is of nominal inch dimensions. The nominalbore diameter for the bearing, as shown in the table of dimensionson page 364, is 3⁄8 inch. Since the letter H appears in the bearingdesignation, the following information will be found opposite H 3⁄8 inthe nominal bore diameter column for the inch series bearingsin Table 4:
inch mmring gauge .6255 15.8877diameter under needle rollers, min. .3765 9.5631diameter under needle rollers, max. .3774 9.5860 The “go” plug gauge is the same size as the minimum
diameter under the needle rollers and the “no go” plug gauge sizeis .0001 inch (.0025 mm) larger than the maximum diameter underthe needle rollers. Therefore the correct ring and plug gaugedimensions are:
inch mmring gauge .6255 15.8877plug gauge,“go” .3765 9.5631plug gauge, “no go”. .3775 9.5885 These same gauge dimensions also apply to JH-68.
Example 2Find the ring gauge and plug gauge dimensions for a HK-1516
bearing.The bearing designation prefix letters HK indicate that, the
bearing is of nominal metric dimensions. The nominal bore diameterfor this bearing, as shown in the table of dimensions on page 367, is15 mm. Opposite “15”, in the nominal bore diameter column formetric series bearings in Table 5, will be found the followinginformation:
mm inchring gauge 20.976 .82583diameter under needle rollers, min. 15.016 .59118diameter under needle rollers, max. 15.034 .59189The “go” plug gauge is the same size as the minimum diameter
under the needle rollers and the “no go” plug gauge size is 0.0020mm (.00008 inch) larger than the maximum diameter under theneedle rollers. Therefore the correct ring and plug gauge dimensionsare:
Bearing bore should be checked with “go” and “no go” pluggauges.The “go” gauge size is the minimum diameter inside theneedle rollers. The “no go” gauge size is larger than the maximumdiameter inside the needle rollers by the following amounts:
Inch Series – 0.0001 inch
0.0025 millimeters
Metric Series – 0.0020 millimeters
0.00008 inch
* The ring gauge sizes for metric series bearings are in accor-dance with ISO N6 lower limit.
Inch - metric conversions given are for the convenience of theuser. The controlling dimensions are in inches for nominal inchbearings and in millimeters for nominal metric bearings.
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
DRAWN CUP NEEDLE ROLLER BEARINGS
BEARING DIMENSIONS MECHANICALLY RETAINED ROLLERS BEARING MOUNTINGLoad Ratings Inch Mounting
Fw D C Basic Basic Working Limiting X S HBore Outside Width Bearing Dynamic Static Load Speed End Shaft Housing Bore
Diameter Designation C r Co Full Thickness RacewayComple- Diameter
+0.000 +0,00 open closed ISO ISO ment(nom.) (nom.) -0.010 -0,25 end end T 281 76 (max.) Bearings (max.) inches inches
inch mm inch mm inch mm lbf lbf lbf lbf rpm inch mm max. min. min. max.
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-78 fordiscussion of shaft and housing design.
Inch - metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Open End Closed End
Caged BearingsCheck for availability.
Drawn cup bearings of nominal inch and metric dimensions with one closed end, whichare not tabulated, may be made available upon request.
Caged drawn cup bearings of nominal inch and metric dimensions, with an engineeredpolymer cage, may be made available upon request.
DRAWN CUP NEEDLE ROLLER BEARINGS
D
C C
MetricSeries
InchSeries
Y
FW FW
Y
366
BEARING DIMENSIONS MECHANICALLY RETAINED ROLLERS BEARING MOUNTINGLoad Ratings Inch Mounting
Fw D C Basic Basic Working Limiting X S HBore Outside Width Bearing Dynamic Static Load Speed End Shaft Housing Bore
Diameter Designation C r Co Full Thickness RacewayComple- Diameter
+0.000 +0,00 open closed ISO ISO ment(nom.) (nom.) -0.010 -0,25 end end T 281 76 (max.) Bearings (max.) inches inches
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Load ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-78 fordiscussion of shaft and housing design.
Drawn cup bearings of nominal inch and metric dimensions with one closed end, whichare not tabulated, may be made available upon request.
Caged drawn cup bearings of nominal inch and metric dimensions, with an engineeredpolymer cage, may be made available upon request.
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
XD
C C
FWFW
FullComplement
Bearing
CagedBearing
SH
shaft surface to be58 HRC or equivalent
Open End Closed End
Full ComplementBearingsCheck for availability.
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-78 fordiscussion of shaft and housing design.
Drawn cup bearings of nominal inch and metric dimensions with one closed end, whichare not tabulated, may be made available upon request.
Caged drawn cup bearings of nominal inch and metric dimensions, with engineeredpolymer cage, may be made available upon request.
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
BEARING DIMENSIONS MECHANICALLY RETAINED ROLLERS BEARING MOUNTINGLoad Ratings Inch Mounting
Fw D C Basic Basic Working Limiting X S HBore Outside Width Bearing Dynamic Static Load Speed End Shaft Housing Bore
Diameter Designation C r Co Full Thickness RacewayComple- Diameter
+0.000 +0,00 open closed ISO ISO ment(nom.) (nom.) -0.010 -0,25 end end T 281 76 (max.) Bearings (max.) inches inches
inch mm inch mm inch mm lbf lbf lbf lbf rpm inch mm max. min. min. max.
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-78 fordiscussion of shaft and housing design.
Drawn cup bearings of nominal inch and metric dimensions with one closed end, whichare not tabulated, may be made available upon request.
Caged drawn cup bearings of nominal inch and metric dimensions, with engineeredpolymer cage, may be made available upon request.
DRAWN CUP NEEDLE ROLLER BEARINGS
D
C C
MetricSeries
InchSeries
Y
FW FW
Y
372
XD
C C
FWFW
FullComplement
Bearing
CagedBearing
SH
shaft surface to be58 HRC or equivalent
Open End Closed End
Full ComplementBearingsCheck for availability.
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-life
calculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
DRAWN CUP NEEDLE ROLLER BEARINGS
373
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-E78 fordiscussion of shaft and housing design.
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
DRAWN CUP NEEDLE ROLLER BEARINGS
375
Inch-metric conversions given arefor the convenience of the user. Thecontrolling dimensions are in inchesfor nominal inch bearings and inmillimeters for nominal metricbearings.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77- E78 fordiscussion of shaft and housing design.
Drawn cup bearings of nominal inch and metric dimensions with one closed end, whichare not tabulated, may be made available upon request.
Caged drawn cup bearings of nominal inch and metric dimensions, with engineeredpolymer cage, may be made available upon request.
ExtraprecisionBearingsOpen end full complement mechanically retained drawn cup needleroller bearings, manufactured to inch standards, are offered withextraprecision specifications. The manufacturing tolerance of thesebearings is one-third that of the precision bearings. In productionoperations using closer tolerances on shaft and housing, they willassemble with consistently lower radial internal clearances than can beexpected with the precision series bearings.
Extraprecision bearings are suitable for those applications requiringclose control of radial play and eccentricity. They are also preferredwhen two bearings are mounted adjacent to each other since thegreater accuracy in manufacture will provide better load distributionbetween the bearings.
Nominal dimensions, load ratings, limiting speeds and other generalspecifications for extraprecision bearings are the same as for thecorresponding “B” or “BH” sizes of drawn cup needle bearings.Consequently, the tabular data on pages 364 to 375 can be used inbearing size selection.
When ordering an extraprecision bearing, add the prefix letter “G” tothe bearing designation. For example, after following the size selectionprocedure outlined on pages E72 to E76, bearing B-1212 is selected,but extraprecision tolerances are required. These are designated byordering a GB-1212 bearing.
To realize the advantages of the expected closer radial internalclearance of the extraprecision bearing, the user must have thecapability of producing housing bore and shaft raceway diameters tothe close tolerances indicated by the tabular data on the facing page.
The resulting total radial internal clearance within the installed GB-1212 extraprecision drawn cup needle roller bearing will lie in the rangefrom 0.0002" (0,005 mm) to 0.0012" (0,030 mm).
Inspection dimensions for the extraprecision bearings are given inthe table at the right. Note that these bearings must be inspected whilemounted in the specified ring gauge. Bearing bores are checked with“GO” and “NO GO” plug gauges. The “GO” gauge size is the minimumdiameter inside the needle rollers. The “NO GO” gauge size is 0.0001"(0,0025 mm) larger than the maximum diameter inside the needlerollers.
Procedures for selecting ring and plug gauge dimensions are thesame as for those involving precision needle bearings as shown onpage 363, except that the ring gauge diameters and diameters insidethe needle rollers must be drawn from the table on this page.
GAUGINGDimensions-inch Dimensions- mm
Nominal Diameter inside Diameter insideBore Ring Needle Rollers Ring Needle Rollers
Diameter Gauge inch Gauge mm
inch inch min. max. mm min. max.1⁄8 0.2473 0.1256 0.1260 6,2814 3,1902 3,20045⁄32 0.2785 0.1569 0.1573 7,0739 3,9853 3,99543⁄16 0.3390 0.1881 0.1885 8,6106 4,7777 4,78791⁄4 0.4328 0.2506 0.2510 10,9931 6,3652 6,37545⁄16 0.4953 0.3131 0.3135 12,5806 7,9527 7,9629
GENERAL NOTESSealed drawn cup needle bearings are prepacked with a generalpurpose ball and roller bearing grease unless otherwise specified.
Lip contact seals limit the bearing operating temperaturebetween -25°F and +225°F (-30°C and +110° C). If the operatingtemperature must be outside of the above range or if the seals areexposed to unusual fluids please consult the Torrington Engineer-ing Department. Limiting speed is based on a shaft contact speedof 2000 fpm (610 m/min.). For outer ring rotation, reduce the listedlimiting speed by one-half.
Load ratings are given in pounds-force: 1 lbf = 0.454kgf = 4.448NRequired Basic Dynamic Load Rating (Cr) = Applied Load • SF • LF • HF (see page E75).
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-lifecalculations taking into consideration the application guidelines and limitations givenin this catalog. Applications involving loads approaching this rating or the tabulatedworking load, whichever is the smaller, should be referred to the TorringtonEngineering Sales Office before a final selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.
Mounting dimensions are based on the inner ring rotating and the outer ring being stationaryrelative to the load. The housing should be of high strength material. See pages E77-78 fordiscussion of shaft and housing design.
See page 361 for mounting procedure.
DRAWN CUP NEEDLE ROLLER BEARINGS
380
Inner Rings forDrawn Cup BearingsCheck for availibility
Hardened inner rings may be used where it is impossible to use the shaftas the inner raceway. Inner rings for use with drawn cup bearings areprovided in inch (IR, IRA) nominal dimensions, designed to meetestablished inch tolerances.
The inner rings are designed to be wider than the matching drawncup bearing. Shaft fillet radii (ra) listed in the tables of dimensions are themaximum allowable to clear the minimum inner ring bore chamfers.
Most inner rings can be provided with a lubrication hole in the centerand a lubrication groove in the bore. When ordering, please specify iflubrication groove and hole are desired.
F
B
d
BORE, O.D. AND WIDTH DIMENSIONSd Inner
Bore Ring d F BDesignation Bore† O.D.† Width
(nominal) inch mm inch mm inch mm
inch mm min. max. min. max. max. min. max. min. max. min. max. min.3⁄16 4,76 IRA-3 0.1895 0.1900 4,813 4,826 0.3750 0.3745 9,525 9,512 0.536 0.526 13,61 13,36
Inner rings for use with drawn cup bearings of nominal metric dimensions, may be madeavailable on request.
† Bore and o.d. tolerance limits correspond to the single mean diameter (the arithmeticalmean of the largest and smallest diameters in a single radial plane).
DRAWN CUP NEEDLE ROLLER BEARINGS
381
Sra max. shaft
fillet
Inner rings for drawn cup bearings are designed to provide a loosetransition fit on the shaft, and should be axially clamped against ashoulder. If a tight transition fit must be used to keep the inner ringfrom rotating relative to the shaft, the inner ring o.d., after beingmounted on the shaft, must not exceed the raceway diameterrequired for the matching drawn cup bearing. See tables of bearingdimensions for the required raceway diameter. In case the o.d. of theinner ring, when mounted on the shaft, exceeds the requiredraceway diameter for the matching drawn cup bearing, it should beground to proper diameter while mounted on the shaft.
The unstamped end of the inner ring should be assembledagainst the shaft shoulder to assure clearing the maximum allowableshaft fillet (ra) indicated in the tables.
Inch-metric conversions are given for the convenience of theuser. The controlling dimensions are in inches for nominal inch innerrings.
MOUNTING DIMENSIONSra Inner S
Shaft Fillet* Ring Shaft DiameterDesignation Transition Fit Loose Transition Fit Tight
*Equal to minimum inner ring bore chamfer at unmarked end. Continued on the next page.
DRAWN CUP NEEDLE ROLLER BEARINGS
382
Inner Rings forDrawn Cup BearingsCheck for availability.
Hardened inner rings may be used where it is impossible to use theshaft as the inner raceway. Inner rings for use with drawn cup bearingsare provided in inch (IR, IRA) nominal dimensions, designed to meetestablished inch tolerances.
The inner rings are designed to be wider than the matching drawncup bearing. Shaft fillet radii (ra) listed in the tables of dimensions arethe maximum allowable to clear the minimum inner ring bore chamfers.
Most inner rings can be provided with a lubrication hole in the centerand a lubrication groove in the bore. When ordering, please specify iflubrication groove and hole are desired.
F
B
d
BORE, O.D. AND WIDTH DIMENSIONSd Inner
Bore Ring d F BDesignation Bore† O.D.† Width
(nominal) inch mm inch mm inch mm
inch mm min. max. min. max. max. min. max. min. max. min. max. min.15⁄16 23,81 IR-1516 0.9370 0.9375 23,800 23,813 1.1250 1.1245 28,575 28,562 1.015 1.005 25,78 25,53
†Bore and o.d. tolerance limits correspond to the single mean diameter (the arithmeticalmean of the largest and smallest diameters in a single radial plane).
Inner rings for use with drawn cup bearings of nominal metric dimensions, may be madeavailable on request.
DRAWN CUP NEEDLE ROLLER BEARINGS
383
Sra max. shaft
fillet
Inner rings for drawn cup bearings are designed to provide aloose transition fit on the shaft, and should be axially clampedagainst a shoulder. If a tight transition fit must be used to keep theinner ring from rotating relative to the shaft, the inner ring o.d., afterbeing mounted on the shaft, must not exceed the raceway diameterrequired for the matching drawn cup bearing. See tables of bearingdimensions for the required raceway diameter. In case the o.d. ofthe inner ring, when mounted on the shaft, exceeds the requiredraceway diameter for the matching drawn cup bearing, it should beground to proper diameter while mounted on the shaft.
The unstamped end of the inner ring should be assembledagainst the shaft shoulder to assure clearing the maximum allowableshaft fillet (ra) indicated in the tables.
Inch-metric conversions given are for the convenience of theuser. The controlling dimensions are in inches for nominal inch innerrings.
MOUNTING DIMENSIONSra Inner S
Shaft Fillet* Ring Shaft DiameterDesignation Transition Fit Loose Transition Fit Tight
These inner rings are designed for either a loose transition fit or aninterference fit on the shaft. These fits, used in conjunction with theproper outer ring fit, will provide the correct operating clearances formost applications. If an interference fit is used for the inner ring, theouter ring should be mounted with a clearance fit. See page 403 forfurther discussion of mounting fits.
The shaft shoulder diameter adjacent to the inner ring must notexceed the inner ring O.D.
The unmarked end of the inner ring should be assembled againstthe shaft shoulder to assure clearing the maximum allowable shaftfillet (ra) indicated in the tables.
S
ra
MOUNTING DIMENSIONSra* S S
Shaft Loose Transition Fit Inner Ring Interference FitFillet Shaft Diameter Designation Shaft Diameter
These inner rings meet Military Standard MS 51962Inch-metric conversions given are for the convenience of the user.
The controlling dimensions are in inches for nominal inch bearings.Load ratings are given in pounds-force:
1 lbf = 0.454 kgf = 4.448 NInner ring diameters and widths listed below are nominal. For
inspection purposes, see tolerance tables on page 405.
F
B
d
HEAVY DUTY NEEDLE ROLLER BEARINGS
BORE, O.D., AND WIDTH DIMENSIONS
415
These inner rings are designed for either a loose transition fit or aninterference fit on the shaft. These fits, used in conjunction with theproper outer ring fit, will provide the correct operating clearances formost applications. If an interference fit is used for the inner ring, theouter ring should be mounted with a clearance fit. See page 403 forfurther discussion of mounting fits.
The shaft shoulder diameter adjacent to the inner ring must notexceed the inner ring O.D.
The unmarked end of the inner ring should be assembled againstthe shaft shoulder to assure clearing the maximum allowable shaftfillet (ra) indicated in the tables.
S
ra
MOUNTING DIMENSIONSra* S S
Shaft Loose Transition Fit Inner Ring Interference FitFillet Shaft Diameter Designation Shaft Diameter
Inch SeriesRC regular clutch, single roller per integral spring
RC-FS regular clutch, single roller per stainless steel springRCB regular clutch and bearing assembly, single roller
per integral springRCB-FS regular clutch and bearing assembly, single roller
per stainless steel spring
Outside Diameter14 = 14⁄16 = 7⁄8"
RC 10 14 10
Bore10 = 10⁄16 = 5⁄8"
Width10 = 10⁄16 = 5⁄8"
Metric SeriesFCS regular clutch, single roller per stainless steel spring
FC regular clutch, multi-roller per stainless steel springFCL-K light series clutch, single roller per stainless steel springFCSB regular clutch and bearing assembly, single roller per
stainless steel springFCB regular clutch and bearing assembly, multi-roller per
stainless steel springFCBL-K light series clutch and bearing assembly, single roller per
INTRODUCTIONFunctionThe Torrington drawn cup roller clutch transmits torque between theshaft and housing in one direction and allows free overrun in theopposite direction. When transmitting torque, either the shaft or thehousing can be the input member. Applications are generally describedas indexing, backstopping or overrunning.
DESIGNThe patented design utilizes the same low profile radial section as drawncup needle roller bearings. The units are compact, light in weight andoperate directly on a hardened shaft. Proper mounting is easilyaccomplished with a simple press fit in the housing.
Precisely formed interior ramps provide surfaces against which therollers wedge to positively lock the clutch with the shaft when rotated inthe proper direction. Transition from the overrun to locked operationnormally occurs with minimal lost motion(backlash).
OPERATIONOperation is in two modes; the overrun mode and the lock mode.Operational mode is controlled by the direction of the clutch or shaftrotation with respect to the locking ramps.
In the overrun mode shown in the drawings below, the relativerotation between the housed clutch and the shaft causes the rollers tomove away from their locking position against the locking ramps in thedrawn cup. The housing and the clutch are thus free to overrun in onedirection, or the shaft is free to overrun in the other direction.
CLUTCH
L
OC
K
Lock FunctionShaft Drives Gear
Clockwise ( White arrows )
or Gear Can Drive Shaft Counter-Clockwise( Black arrows )
LOCK
LOCK
IS STATIONARY
IS STATIONARY
LOCK
H O U S I N G
(DRIVER)
(DRIVEN)
LOCK
H O U S I N G(DRIVER)
(DRIVEN)
Clearance between the rollers and cup rampsis exaggerated in these drawings.
OVERRUNS CLOCKWISE
H O U S I N G
CLUTCH
STATIONARY
S H A F T
OVERRUNSCOUNTER-CLOCKWISE
CLUTCH
S H A F T
ROTATES
CLUTCH
S H A F T
ROTATES
CLUTCH
S H A F T
ROTATES
H O U S I N G
Two basic configurations are produced:
clutch only - Use with external radial support (usually two drawncup needle roller bearings). Separate bearings position the shaft andhousing concentrically and carry the radial load during overrun.
clutch and bearing assemblies - Use without additional radialsupport. An integral assembly within a single drawn cup, in which tworoller bearings straddle the clutch.
In the lock mode shown in the drawings below, the relative rotationbetween the housed clutch and the shaft is opposite to that in theoverrun mode. The rollers, assisted by the leaf type springs, becomewedged between the locking ramps and the shaft to transmit torquebetween the two members. Either the member housing the clutch drivesthe shaft in one direction, or the shaft can drive the clutch and itshousing member in the other direction.
Clutch Only
Clutch and Bearing Assembly
or Gear Overruns on Shaft Clockwise(Black arrow)
DRAWN CUP ROLLER CLUTCHES
495
Drawn Cup Roller Clutch Drawn Cup Clutch andType FC Bearing Assembly
with Steel Springs Type FCBwith Steel Springs
Drawn Cup Roller Clutch Drawn Cup Clutch andTypes FCS, FCL-K and RC-FS Bearing Assembly
with Steel Springs Types FCBL-Kand RCB-FS
with Steel Springs
Drawn Cup Roller Clutch Drawn Cup Clutch andType RC Bearing Assembly Type RCB
with Integral Springs with Integral Springs
Metric SeriesFCS – regular clutch, single roller per stainless steel
springFC – regular clutch, multi-roller per stainless steel
springFCL-K – light series clutch, single roller per stainless
steel springFCSB – regular clutch and bearing assembly, single
roller per stainless steel springFCB – regular clutch and bearing assembly, multi-
roller per stainless steel springFCBL-K – light series clutch and bearing assembly, single
roller per stainless steel spring
DRAWN CUP ROLLER CLUTCHES
CONSTRUCTIONIn many respects, construction is similar to that of drawn cup bearings.Design and manufacture of drawn cup clutches, just as with drawn cupbearings, was pioneered and developed by Torrington.
The interior ramps which control the lockup and free run of the clutchare formed during the operation of drawing the cup. The ramps are casehardened to assure long wear life. The incorporation of ramp forminginto the cup drawing operation is a manufacturing innovation thatcontributes much to the units low cost.
Two types of precision molded clutch cages are employed. TypesRC and RCB utilize a one-piece cage of acetal resin plastic with integralleaf style springs. Types FC, FCS, FCL-K, RC-FS, FCB, FCBL-K andRCB-FS use a glass fiber reinforced nylon cage equipped with insertedstainless steel leaf springs. The stainless steel springs permit higherrates of engagement, and achieve a greater spring life. The nylon cagepermits operation at higher temperatures than the acetal resin cage.
Types RCB, FCB, FCBL-K and RCB-FS clutch and bearingassemblies have cages for retention and guidance of the rollers in thebearings located on both sides of the clutch unit.
SPECIAL CLUTCHESTorrington manufactures many special clutches not listed in this catalog.Where volume justifies tooling costs, special clutches may result in alower unit cost or, in the event of additional costs, may provide aneconomical solution to an unusual design problem. If you think a specialclutch is indicated, please contact your local Torrington representativefor a review of your application.
IDENTIFICATIONThe prefix letters in the designation of the Torrington drawn cup rollerclutches and drawn cup roller clutch and bearing assemblies denotewhether these are manufactured to inch or metric nominal dimensions.Designation codes for clutches and clutch and bearing assemblies withinch nominal dimensions begin with the letter “R”. Those for clutchesand clutch and bearing assemblies with metric nominal dimensionsbegin with the letter “F”.
The basic types of clutches and clutch and bearing assemblies arelisted below:
Inch SeriesRC – regular clutch, single roller per integral spring
RC-FS – regular clutch, single roller per stainless steelspring
RCB – regular clutch and bearing assembly, singleroller per integral spring
RCB-FS – regular clutch and bearing assembly, singleroller per stainless steel spring
496
DRAWN CUP ROLLER CLUTCHES
Stair SteppersNordic Trak and otherAthletic Equipment
LawnmowerDifferential
Tape Dispensersand SimilarWeb Roll FeedMechanisms
ConveyorRollers
Chainsaw Starters
PaperFeed Rollsin BusinessMachines
APPLICATIONTorrington clutches and clutch and bearing assemblies are successfullyapplied in a wide range of commercial products where indexing,backstopping and overrunning operations must be performed reliably.The sketches on these pages illustrate some of the many possibleuses.
When applying the clutch-only unit, separate bearings on each sideof the clutch are required to position the shaft concentrically with thehousing and to carry the radial loads during overrun. Drawn cup needleroller bearings with the same radial section as the clutch should beused in the through bored housings for simplicity and economy. Twoclutches can be used side by side for greater torque capacity.
Where the radial loads are light, the clutch and bearing assemblycan be used without additional support bearings. This reduces theoverall assembly width, the number of stocked and ordered parts, andassembly costs as well.
Torrington Drawn Cup Roller Clutches are manufactured to commercialhardware standards and are used extensively in appliances, businessmachines, industrial and recreation equipment and a wide range of otherapplications.
In any application where our clutch may be considered, it will be partof a system in which the operating conditions and the clutch mounting willaffect its function. Therefore, before any clutch selection is made, it isimportant that the following catalog sectionbe carefully studied to understand the effects of these factors.
Consideration should be given to operating conditions such as:
• Magnitude of externally applied torque as well as inertial torque
• Magnitude of applied radial loads during overrunning
• Potential for vibration or axial shaft movement within the clutch duringengagement
• Engagement rate, as it pertains to the selection of stainless steel orplastic leaf springs
• Oil lubrication supply during high overrunning speeds
• External and internal environmental temperatures that can affectclutch performance
• Lubricant selection effect on clutch engagement
• Indexing inaccuracies resulting from backlash (lost motion)
Consideration should be given to the Shaft and Housing design require-ments such as:
• Shaft hardness and strength particularly when approaching torquerating limits
• Shaft roundness, taper and surface finish necessary to ensuresufficient fatigue life and torque carrying ability
• Housing strength (hardness and cross section) to support the appliedtorque loads
• Housing roundness, taper and surface finish necessary to ensureuniform torque and load distribution
A test program under all expected operating conditions should becarried out before putting a new application into production. Torringtonapplication engineers are constantly working with and testing newapplications, therefore, their experience can be of great help to thedesigner considering the use of a drawn cup roller clutch.
Clutch and Bearing Arrangement Clutch and Bearing AssemblyHeavy Loads Light Loads
497
DRAWN CUP ROLLER CLUTCHES
HOUSING DESIGNDrawn cup clutches and clutch and bearing assemblies are mountedwith a simple press fit in their housings. Through bored and chamferedhousings are preferred. Provisions for axial location, such as shouldersor snap rings, are not required. The case hardened cups have a longfatigue life, but must be properly supported to realize this benefit. Steelhousings are preferred and must be used for applications involving hightorque loads to prevent radial expansion of the clutch cups. Therecommended minimum housing outside diameters in the tables ofdimensions are for steel.
The housing bore should be round within one-half of the diametertolerance.
The taper within the length of the outer ring should not exceed0.0005 inch or 0.013 mm.
The surface finish of the housing bore should not exceed 125microinches, a.a. (arithmetic average) or 3.2µm (on the Ra scale).
Low strength housings (non-steel, sintered metals and some plastics)may be entirely satisfactory in lightly loaded applications. When usingnon-steel housings, thoroughly test designs.
Adhesive compounds can be used to prevent creeping rotation of theclutch in plastic housings with low friction properties. Adhesives will notprovide proper support in oversized metallic housings. When usingadhesives, care must be taken to keep the adhesive out of the clutchesand bearings.
SHAFT DESIGNThe clutch or clutch and bearing assembly operates directly on the shaftwhose specifications of dimensions, hardness and surface finish are wellwithin standard manufacturing limits.
Either case hardening or through hardening grades of good bearingquality steel are satisfactory for raceways. Steels which are modified forfree machining, such as those high in sulfur content and particularlythose containing lead, are seldom satisfactory for raceways.
For long fatigue life, the shaft raceway, must have a hardnessequivalent to 58 HRC (ref, ASTM E-18), and ground to the recom-mended diameter shown in the tables of dimensions. It may be throughhardened, or it may be case hardened, with an effective case depth of0.030 inch (0.8 mm) (Effective case depth is defined as the distancefrom the surface inward to the equivalent of 50 HRC hardness level aftergrinding.)
Taper within the length of the raceway should not exceed 0.0003inch (0.008 mm), or one-half the diameter tolerance, whichever issmaller. The radial deviation from true circular form of the racewayshould not exceed .0001 inch (0.0025 mm) for diameters up to andincluding 1 inch (25.4 mm). For raceways greater than 1.0 inch or 25mmthe allowable radial deviation may be greater than .0001 inch(0.0025 mm) by a factor of raceway diameter (in inches) divided by 1.0or a factor of raceway diameter (in mm) divided by 25.4. Surface finishon the raceway should not exceed 16 microinches a.a. (arithmeticaverage) or 0.4 µm (on the Ra scale). Deviations will reduce the loadcapacity and fatigue life of the shaft.
Rack Indexing Drive
MotorBackstops
2-Speed GearboxwithReversing Input
Timing MotorFreewheels
Washing MachineTransmission
498
DRAWN CUP ROLLER CLUTCHES
INSTALLATION
Simplicity of installation promotes additional cost savings. The drawncup roller clutch, or the clutch and bearing assembly, must be pressedinto its housing. Procedures are virtually identical with those for installingdrawn cup bearings as detailed on page 361. The unit is pressed intothe bore of a gear hub or pulley hub, or housing of the proper size, andno shoulders, splines, keys, screws or snap rings are required.
Installation procedures are summarized in the following sketches:
IMPORTANT: The mounted clutch or clutch and bearing assemblyengages when the housing is rotated relative to the shaft in the directionof the arrow and LOCK marking (← LOCK) stamped on the cup. Makesure that the unit is oriented properly before pressing it into its housing.
Use an installation tool as shown in the diagram above. If clutch isstraddled by needle roller bearings, press units into position inproper sequence and preferably leave a small clearance betweenunits.
When assembling the shaft, it should be rotated during insertion.The end of the shaft should have a large chamfer or rounding.
Make sure that the housing bore is chamfered to permit easyintroduction of the clutch and bearing or the clutch unit. Press unitslightly beyond the chamfer in the housing bore to assure fullseating. Through bored housings are always preferred. If thehousing has a shoulder, never seat the clutch against the shoulder.For further details see page 361.
15°
Pilot Dia. is0.02" ( 0.5mm )less than nom.
Shaft Dia.
Amountof
Recess
Use"O" Ringon Pilot
Long Leadon Pilot
"O" Ring holds unit onPilot during installation
Amount of Recess
Chamfer
Use an arbor press or hydraulic ram press which will exertsteady pressure. Never use a hammer or other tool requiringpounding to drive the clutch into its housing.
499
DRAWN CUP ROLLER CLUTCHES
APPLIED LOADSThe clutch-only unit is designed to transmit purely torque loads. Appliedtorque should not exceed the catalog ratings which are based on thecompressive strength of well-aligned clutch components. Bearings oneither side of the clutch are required to assure concentricity between theshaft and the housing and to support radial loads during clutch overrun.Integral clutch and bearing assemblies are available for this purposewhere the radial loads are light.
In determining the total torque load on a clutch, it is essential toconsider the torque due to inertial forces developed in the mechanism, inaddition to the externally applied torque. The larger the clutch and thegreater the mass of the mechanism controlled by it, the more importantthis consideration becomes.
Clutch lockup depends upon static friction. For this reason applica-tions involving severe vibrations or axial motion of the shaft within theclutch are to be avoided. Applications in which there are overhanging oroverturning loads should incorporate bearings which will maintainalignment between the shaft and the clutch housing. Consult yourTorrington Engineering Sales Office for recommendations.
LUBRICATIONOil is the preferred lubricant, as it minimizes wear and heat generation.For those applications where oil is not practical, clutches are packed witha soft grease containing mineral oil. Thick grease will retard rollerengagement and can cause individual rollers to slip, possibly overload-ing any engaged rollers.
TEMPERATURETemperature extremes can cause clutch malfunctions and failure. Themolded acetal resin plastic cage with integral springs holds its necessaryresiliency and strength when the operating temperature within the clutchis kept below 200°F (93°C). The clutch with reinforced nylon cage andseparate steel springs operates well at temperatures up to 250°F(121°C) continuously and to 300°F (150°C) intermittently. Excessivethickening of the lubricant at low temperatures may prevent some or allof the rollers from engaging. New applications should be tested underexpected operating conditions to determine whether or not temperatureproblems exist.
BACKLASHBacklash, or lost motion, prior to engagement is minimal. The variationin backlash from one cycle to another is extremely low. Grease lubrica-tion or improper fitup (housing bore and shaft diameter) may increasebacklash. Angular displacement between the shaft and housing in-creases as an applied torque load is increased.
RATE OF ENGAGEMENTClutch lockup depends upon static friction. Axial motion between shaftand clutch rollers prevents lockup.
Clutches with integral springs engage satisfactorily at cyclic rates upto 200 engagements per minute. Intermittent operation at higher rateshas been successful. The steel spring type clutches have provendependability at rates up to 6000 or 7000 engagements per minute.Even higher cyclic rates may be practical. Since grease may impairengagement at high cyclic rates, a light oil should be used.
OVERRUN LIMIT SPEEDExacting limiting speeds are not easily predictable. The value for eachclutch given in the tabular data is not absolute but serves as a guide forthe designer. Oil lubrication is absolutely necessary for high speedoperations. Consultation with the Engineering Sales Office is recom-mended when overrunning speeds are high.
INSPECTIONAlthough the outer cup of the clutch is accurately drawn from strip steel,it can go slightly out of round during heat treatment. When the assemblyis pressed into a ring gauge or properly prepared housing of correct sizeand wall thickness, it becomes round and is properly sized. Directmeasurement of the outside diameter of a drawn cup assembly is anincorrect inspection procedure. The proper inspection procedure is asfollows:
1. Press the assembly into a ring gauge of the proper size as given inthe tabular data.
2. Gauge the bore with the specified plug gauges of the proper size, asgiven in the tables of dimensions.
a. The locking plug is rotated to insure lockup when the clutch isoperated on a low limit shaft and is mounted in a high limithousing strong enough to properly size the clutch.
b. The overrun plug is rotated to insure free overrunning whenthe clutch is operated on a high limit shaft and is mounted in alow limit housing.
c. The go plug and no go plug insure proper size of thebearings in the clutch and bearing assemblies.
Gauge sizes are listed in the tables of dimensions. Plug gauge sizesreflect adjustment for the loose and tight conditions resulting from high orlow housings and shafts. Inch to metric and metric to inch conversionsare listed for the convenience of the user, but the designer shouldunderstand that the controlling dimensions are in inches for nominal inchassemblies and millimeters for nominal metric assemblies.
500
D FW
CC
FW
The mounted clutch engages when thehousing is rotated relative to the shaft inthe direction of the arrow marking(←LOCK) stamped on the cup.
DIMENSIONS AND RATINGSFw D C Clutch Designation Torque Z
* Suffix “-FS” is not always stamped on the clutch cup. Type RC-FS with stainless steel springs is always readily identified by RED clutch cage.
†Torque ratings are given in pound force inches: 1 lbf • in = 0.113 N • m = 0.0115 kgf • m
Type DC Roller ClutchesBefore ordering any clutch check for availabliity.
Nominal dimensions with rounded conversions are shown below.Shaft raceway and housing bore diameters necessary for propermounting and operation are listed on the opposite page.
Types FC, FCS, FCL-K and RC-FS clutches have stainless steelsprings inserted in the, molded cage to position the rollers forinstantaneous lockup.
Type RC clutches have springs integrally molded with the cageto position the rollers for instantaneous lockup.
Proper inspection requires installation of the clutch in a ring gauge andthen checking the bore with the appropriate plug gauges. Please readthe section on “INSPECTION” on page 499.
Types FC, FCS and FCL-K clutch series are manufactured to metricdimensions. Inch dimensions shown are for the convenience of thedesigner. The controlling dimensions are in millimeters.
Types RC and RC-FS clutch series are manufactured to inchdimensions. Metric dimensions shown are for the convenience of thedesigner. The controlling dimensions are in inches.
When applying these clutches, it is important that separate bearingsbe used adjacent to the clutches to carry radial loads and assureconcentricity between the shaft and the housing.
For full details on “INSTALLATION” see page 498.
Z SH
Shaft surface to be58 HRC or equivalent
502
DRAWN CUP ROLLER CLUTCHES
The mounted clutch and bearingassemblies engages when thehousing is rotated relative to the shaftin the direction of the arrow marking(←LOCK) stamped on the cup.
Type DC Roller Clutch andBearing AssembliesNominal dimensions with rounded conversions are shown below.Shaft raceway and housing bore diameters necessary for propermounting and operation are listed on the opposite page.
Types FCB, FCBL-K and RCB-FS clutch and bearing assem-blies have stainless steel springs inserted in the molded cage toposition the rollers for instantaneous lockup.
Type RCB clutch and bearing assemblies have springs integrallymolded with the cage to position the rollers for instantaneous lockup.
Before ordering any clutch and bearing assemblies check foravailability.
DIMENSIONS AND RATINGSFw D C Clutch and Bearing Torque Z Bearing
Bore O.D. Width Assembly Designation Rating Minimum O.D. of Basic Dynamic Bearing Overrun† Steel Housing Load Rating § Working Limiting
with with for Rated Torque Cr ISO Load Speed0.000 +0,00 Stainless Integral 281
(nominal) (nominal) -0.010 -0,25 Steel Springs Springs T (max)
inch mm inch mm inch mm lbf • in. inch mm lbf lbf lbf rpm
T Symbol denotes Torrington Basic Dynamic Load Rating to be used in load-life calculationstaking into consideration the application guidelines and limitations given in this catalog.Applications involving loads approaching this rating or the tabulated working load,whichever is the smaller, should be referred to your Engineering Sales Office before afinal selection is made.
Load Ratings are based on a minimum raceway hardness of 58 HRC or equivalent.
Proper inspection requires installation of the clutch and bearingassembly in a ring gauge and then checking the bore with the appropri-ate plug gauges. Please read the section on “INSPECTION” on page499.
Types FCB and FCBL-K clutch and bearing assemblies aremanufactured to metric dimensions. Inch dimensions shown are for theconvenience of the designer. The controlling dimensions are inmillimeters.
Types RCB and RCB-FS clutch and bearing assemblies aremanufactured to inch dimensions. Metric dimensions shown are for theconvenience of the designer. The controlling dimensions are in inches.
For full details on “INSTALLATION” see page 498.
Z SH
Shaft surface to be58 HRC or equivalent
.010" (.25 mm) MIN.
GAUGING MOUNTINGInch Mounting Metric Mounting
Clutch Clutch Overrun Bearing S H S HRing Locking and Bearing No Go Shaft Raceway Housing Shaft Raceway Housing
gauge Plug Go Plug Plug Diameter Bore Diameter Bore
inches inches millimeters millimeters
inch mm inch mm inch mm inch mm max min min max max min min max