Page 14 - e3328g

7. Installation

(1) Mounting tolerance
Mounting tolerance results in harmful effects such as shortened operating life, deterioration in motion accuracy,
and friction variation.
NSK particularly focuses on operating life, and sets an operating life value of more than 10 000 km calculated
under the following conditions as mounting tolerance:

● The load per roller slide is 10% of basic dynamic load rating C.

● The rigidity of machine is infinite.

The tolerance in Fig. 14 is shown in the Table 13 as typical tolerance.

Fig. 14 Mounting tolerance Table 13 Mounting tolerance of RA series Unit: µm

e2 Model Parallelism tolerance of Height tolerance of
500 No. two roller guides e1 two roller guides e2
Z1 Z3, ZZ
Z1 Z3, ZZ

e1 RA15 – 5
–
RA20 –
7

RA25 14 9

RA30 18 11 150 µm /
RA35 21 13 290 µm / 500 mm
RA45 27 17 500 mm

RA55 31 19

RA65 49 30

(2) Shoulder height and corner radius of mounting surface
When using the shoulders, which rise perpendicularly to the mounting surface, for accurate installation of a roller
guide, refer to Fig. 15 and Table 14 for the dimensions.

Fig. 15 Datum face of roller guide and shoulder Table 14 S houlder height and corner radius Unit: mm
of attachment

rb Model No. Shoulder Height Chamfer (maximum)
H´ H´´
Rail H´ RA15 ra rb
ra 34
0.5 0.5

ra rb H˝ RA20 4 5 0.5 0.5

RA25 4 5 0.5 1.0

Roller Slide RA30 5 6 1.0 1.0

RA35 5 6 1.0 1.0

RA45 6 8 1.5 1.0

RA55 7 10 1.5 1.5

RA65 11 11 1.5 1.5

13