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Type and Part CodeApplicable shaft
diameter

TypeFeaturePart CodeRNAST
ф 7 ~ ф 60

NAST type without inner ring.

ф 6 ~ ф 50

Thick walled outer ring.
Separable bearing with combined needle roller withprecision cage.

Type15
Bore diameter

R
R: Crowned outer ring
None: Cylindrical outer ring

RNAST(Separable type)

NAST
Type15
Bore diameter

R
R: Crowned outer ring
None: Cylindrical outer ring

NAST(Separable type)

NASTф 6 ~ ф 50

Separable bearing in which labyrinth seal is formed withcombined side plate at both sides of inner ring of NASTtype.
(NAST-ZZUU type comes with seals)

Type15
Bore diameter

ZZ

UU

Z Z: With shields

R: Crowned outer ring
X: Cylindrical outer ring
UU: Sealed type
None: Shield type

NAST-ZZ(Separable type)

NART

ф 5 ~ ф 50

Non-separable bearing with fixed side plate at inner ring.
Mitigate eccentric load with spherical shape at outer
diameter of outer ring (code R).
(NART-UUR type comes with seals)

Type15
Bore diameter

UU
UU: Sealed type
None: Shield type

NART-R(Non-separable type)186

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VR
R: Crowned outer ring
X: Cylindrical outer ring

V: Full complement
None: With cageф 15 ~ ф 50

NURT-R(Non-separable type)

RRoller follower which allows high radial loading andmoderate axial loading with integrated cylindrical rollers
in double rows.
Non-separable bearing with fixed shield plate.
Crowned outer ring.
(NURT-X type comes with cylindrical outer ring)

NURT
Type

15
Bore diameter

R
R: Crowned outer ring
X: Cylindrical outer ring

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Structure and Features

Accuracy standard

Roller follower is a bearing with integrated “roller” featuring high rigidity. Its primary application is in a guideroller to have its contacting member travel in linier motion in direction of tangent using rotation of outerring.
Outer ring of the roller follower is designed with thick ring in order to provide high rigidity to endure heavy
load or impact load at portion to contact with the associated objects.
Type of roller follower mainly consists of separate type, which have separated inner ring and outer ring, andnon-separate type, whose inner ring has fixed side plate.
Also, various types with shapes and structures are available in accordance with application. There are two types ofouter rings: a crowned outer ring and a cylindrical outer ring. The crowned outer ring is suited for absorbing eccentricload since it absorbs angular misalignment due to a mount error. Cylindrical outer ring is more effective for heavy duty
load since it contacts with larger area of the associated objects and mitigates the contact surface pressure. They have
two internal mechanisms – one with cage and one with full complement. A roller follower with cage is suitable forhigh speed application due to the guiding feature of cage enabling the rotation of "rollers" to be stable. Comparedwith cage type, full complement type is more effective for applications with low-speed operation of heavy load due to
its larger load rating. Full complement type also includes double-row cylindrical roller type which allows moderate
axial loading.

Outer ring

Outer ring
Needle roller

Needle roller

Cage

Cage

Inner ring

Inner ring

Roller followers are manufactured in accordance with the following accuracies.
Table-1 Accuracy
Unit: µm
Category Crowned outer Cylindrical outer
Nameringring
Dimension tolerance of outer ring outer diameter0
Refer to Table-3(D)-500Dimension tolerance of outer ring width (C)-1200Tolerance of inner ring width (B)Separable-120
NonTolerance of bearing width (B)h12separable
Fw

Separable

Nominal inner ring bore
diameter d (mm)Refer to Table-11 on page 27

Table-2 Accuracy of inner ring
Unit: µm
Deviation of mean bore
Tolerance of radial runout
diameter in a single planeof inner ring
Δ dmp

OverIncl.

highlowmax.

2.5

100-81010

180-81018300-101330500-1215Side plate

Structure of type NAST

Structure of type NAST..ZZ

Outer ring
Needle roller

SealOuter ring
Needle roller
Shield plateCageCage

Inner ring

Inner ring

Nominal outer ring bore
diameter D (mm)Table-3 Accuracy of outer ring
Unit: µm
Deviation of mean outer
Tolerance of radial runout
diameter in a single planeof outer ring (max.)
Δ Dmp

OverIncl.

highlowmax.

6180-815

18300-91530

500-112050

800-132580

1200-1535Side plate
Side plate

Structure of type NART..UUR188NOSE SEIKO CO.,LTD.

Structure of type NURT..R

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Track load capacity

Table below indicates radial internal clearance of roller follower.
Table-4 Radial internal clearance

Unit: µm

Part code

Radial internal clearance

Separable

Non-separable

Double row cylindricalroller

min.

max.

NAST6

NART5R ～ 6R

̶520

NAST8 ～ 12

NART8R ～ 12R

̶525

NAST15 ～ 25

NART15R ～ 25R

̶

1030

NAST30 ～ 40

NART30R ～ 40R

̶

1040

NAST45 ～ 50

NART45R ～ 50R

̶

1550

̶

̶

NURT15R ～ 30-1R

025̶

̶

NURT35R ～ 40-1R530

̶̶

NURT45R ～ 50-1R

535

Track load capacity means a permissive load under which the outer ring of cam follower and the mating
surface are allowable to be used over a long period without causing any deformation nor compression mark.
Track load capacity depicted in dimension table indicates a value for which hardness of contacting steel
member is assumed to be HRC40. In the case that the hardness of contacting member is not HRC40, trackload capacity in the dimension table shall be multiplied by value of track capacity factor obtained byFigure-1.
7
Track capacity factor

Radial internal clearance

6Crowned outer ring
Cylindrical outer ring5432102025303540455055 58Hardness [HRC]

Figure-1 Track capacity factor

Lubrication

Fits
Table below indicates recommended fits between roller follower and its mounting shaft.
Table-5 Shaft fits
TypeSeparable

Without innerringWith inner ringNon-separable
Double row cylindrical roller

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Tolerance grade
k5,k6
g6,h6

All the JNS roller followers are lubricated with pre-packed high quality lithium soap-based grease grade 2(RoHS compliant) and are ready to use. For applications requiring high prevention measure against invasionof foreign matter or leakage of lubricant, products with seal (part code--UU) which integrate special
synthetic lubber with high abrasion resistance are also available.
Grease shall be packed up to volume approximately one-third to one-half of internal space of bearing.
Lubrication interval varies depending on operation condition. Referential interval may be every six to twenty
four months for roller followers with cages and every one to six months for full complement type withgrease in the same type.
Some excessive grease may leak at the beginning of usage or immediately after re-greasing even for theproducts with seal. Aging operation period is recommended prior to application in which no contamination
by grease is allowed in and around device. Wipe and clean any leaked extra grease after this operation.

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Mounting
Mounting part

Mounting method● Thrust load may cause damage to side plate, outer ring or roller follower since it is designed so as toTo prevent pre-mature failure of roller follower, lubrication hole of inner ring shall be located outside ofloading range (on the side to receive load).

support load in radial direction. It is recommended to design and assemble to avoid thrust load.
● Application with roller follower without inner ring requires heat treatment and grinding finish of shaft.
Surface hardness of the shaft shall be HRC58 to 64, and surface roughness shall be R a 0.2 μ m or less forthis application.
● Side plate of non-separate type roller follower is pressed-in to fix it. Application in a manner to push theside plate shall be avoided in order to prevent risk of abnormal rotation under external force.
● Crowned outer ring is recommended in the case that contact between the outer ring and contacting

member track surface is not smooth and even.
● When mounting NART, NAST-ZZ and NURT type, dimension "a" must be more than it described inadimension table in order to protect the side plate.

NAST..ZZ Example of mounting

NART..UUR Example of mounting

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