Each roller is a sealed double-row angular contact ball bearing built onto its own stud. The stud axis is offset 1 mm from the roller axis (2 mm on FR22). Turn the stud before you tighten the bolt and the roller moves up to twice the eccentricity toward or away from the rail. You remove play or set a light preload without shims.
Typical applications: rack-and-pinion gantries on V-guide rails, transfer and assembly lines, ring slides, cutting and welding carriages, and doors or shuttles that run on a flat rail.
Dimensions in millimetres. The V-groove is checked with a gauge circle: A is the distance from the roller axis to the centre of that circle. e is the stud eccentricity.
The collar stands 1 mm proud of the roller face, so the outer ring does not rub the mounting plate. FR and LR rollers of the same size (10, 15, 20, 25, 35) share the same stud, so both fit the same mounting holes.
Load ratings and axial clearance
C0 is the static load rating. C is the dynamic load rating for a rated life of 10⁶ m and 10⁸ m of travel. Stainless steel rollers have lower ratings: ask for the values.
Model
C0 (N)
C, 10⁶ m (N)
C, 10⁸ m (N)
Limiting speed (r/min)
Mass ≈ (kg)
Axial clearance, normal (µm)
FR10
5300
4900
1060
12000
0.15
+6 / +23
LR10
5300
4900
1060
12000
0.18
+6 / +23
FR15
6800
7200
1560
9000
0.25
+6 / +23
LR15
6800
7200
1560
9000
0.18
+6 / +23
FR20
9500
10200
2200
7000
0.5
+7 / +25
LR20
9500
10200
2200
7000
0.5
+7 / +25
FR22
8600
9000
2000
7000
0.6
+6 / +23
FR25
15000
16300
3530
5600
1.1
+8 / +27
LR25
15000
16300
3530
5600
1.1
+8 / +27
FR35
32000
28400
6150
3600
2.8
+11 / +33
LR35
32000
28400
6150
3600
3
+11 / +33
Preloaded rollers have an axial clearance of −3 / +5 µm. Values are for bearing steel rollers.
Interchange
Our model numbers follow the common FR / LR designation. The table lists equivalent part numbers. Add Z for the concentric (fixed) stud, for example FR15Z.
NLHB
Güdel
KH
YYC
FR10
FR10 · 900710
—
—
LR10
LR10 · 900810
—
—
FR15
FR15 · 900715
VR15A
UV15Y
LR15
LR15 · 900815
FR15A
UR15Y
FR20
FR20 · 900720
VR20A
UV20Y
LR20
LR20 · 900820
FR20A
UR20Y
FR25
FR25 · 900725
VR25A
UV25Y
LR25
LR25 · 900825
FR25A
UR25Y
FR35
FR35 · 900735
VR35A
UV35Y
LR35
LR35 · 900835
FR35A
UR35Y
Brand names and part numbers are used only to identify interchangeable rollers. Check the dimensions above before you replace a roller.
Dimension drawings
FR10 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
LR10 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
FR15 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
LR15 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
FR20 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
LR20 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
FR22 dimension drawing. Eccentricity e = 2 mm is shown schematically: the dash-dot line on the stud is the stud axis.
FR25 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
LR25 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
FR35 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
LR35 dimension drawing. Eccentricity e = 1 mm is shown schematically: the dash-dot line on the stud is the stud axis.
How to set the roller with the eccentric stud
Fit the roller through the mounting plate with the collar face against the plate. A bolt passes through the bore and its head sits in the counterbore on the roller face.
Put a pin spanner in the two holes on the roller face and turn the stud. The roller moves toward or away from the rail. Half a turn gives the full travel, twice the eccentricity.
Stop when the roller touches the rail with no play. For a light preload, turn a little further until the carriage still moves smoothly by hand.
Hold the stud with the spanner and tighten the bolt. Move the carriage over the full stroke and check that it runs without tight spots.
A common layout uses concentric rollers on one side of the rail as the reference and eccentric rollers on the other side to take up play.
We turn, heat treat, grind and assemble these rollers in our Cixi factory. On request we also supply concentric (fixed) studs for the reference side, stainless steel rollers for wash-down areas, normal or preloaded bearing clearance, and rollers to your drawing: other outside diameters, groove angles, stud diameters and lengths. Send the rail size or rail drawing, load, speed, mounting plate thickness and quantity.
Frequently asked questions
What does the eccentric stud on a track roller do?
The stud axis is offset from the roller axis, 1 mm on these models and 2 mm on FR22. Turning the stud moves the roller up to twice the eccentricity toward or away from the rail, so play can be removed or a light preload set without shims.
Is FR15 the same as an FR flanged miniature bearing?
No. FR10 to FR35 here are eccentric stud V-groove track rollers. The FR inch flanged miniature bearings, such as FR155 or FR168, are a different product.
Which rail does an FR roller run on?
FR rollers run on 90° V-guide rails and V-rail racks. Choose the size by the rail: send the rail drawing or the rail profile and we confirm the size.
What is the difference between FR35 and LR35?
FR35 has a 90° V-groove for a V-guide rail. LR35 runs on a flat rail. Its outer ring is slightly crowned (R500), so a small tilt of the rail does not load the ring edge. Both use the same Ø40 stud, collar and adjusting holes, so one carriage can carry both.
Can I get these rollers with a fixed stud?
Yes. We make a concentric (fixed) stud version. Concentric rollers are often fitted on the reference side of the rail and eccentric rollers on the other side.
