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Roller Guide RA Series

5. Smooth motion

Installing a retaining piece between rollers and restraining the skew peculiar to roller bearings achieve smooth
motion. The reduction of friction variation provides stable tracking in the complicated trajectory control.

Retaining piece Roller Motion smoothness of RA series Motion smoothness of RA series
Recirculation can be equivalent to competitor’s product 40
conducted smoothly 40
by maintaining roller Without retaining piece 30
attitude. 30
20
Rail 20
10
10
00 100 200 300 400 500
00 100 200 300 400 500 Distance of movement, mm
Distance of movement, mm

Measured motion smoothness
Friction force, N
Friction force, N

6. Low friction

Using rollers for rolling elements helps minimize dynamic friction.

Conventional linear guide for machine tools #35; RA35AN; medium preload (Z3)
medium preload (Z3)
200 400 600 800 1 000 1 200
Measurement conditions Friction force, N 40 Friction force, N 40 Distance of movement, mm
• Lubrication: Oil (VG68) 30 30
• Feeding speed: 1 m/min 20 20
10 10
200 400 600 800 1 000 1 200
0 Distance of movement, mm 0
–10 –10
–20 –20
–30 –30
–400 –400

Comparison of measured dynamic friction force

7. Highly dust-proof and maintenance-free operation Amount of foreign matter passing through, g 0.060 Conventional linear guide RA series
0.050 for machine tools with rail cover
Roller slides include high performance seals as standard equipment. 0.040
The seal completely blocks the entry of foreign matter into the rolling 0.030
surface and prevents loss of performance. In addition, rail covers✽ are 0.020
also available for severe operating conditions. (Rail covers reduce the 0.010
amount of foreign matter to 1/10 that of conventional linear guide for 0.000
machine tools.)
The highly regarded NSK K1™ lubrication unit is also available to Example results of foreign matter invasion test
satisfy customer needs for long-term, maintenance-free operation.

✽ Rail covers are only available for the models of RA25 to RA65.

8. Low noise Microphone position: 5 00 mm above rail Noise level, dB (A) 80
Lubrication: Oil (VG68) RA45BN
A retaining piece is provided
between rollers to prevent collision 75 Competitor’s
of rollers to minimize noise. product

70
65

60

55

50

45

4010 100 1 000
Speed, m/min

Example measurement of noise test

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