Renishaw TONiC FS T40x1 Series Functional Safety Manual page 12

Step 2
TONiC RESM20 Functional Safety installation guide and safety manual
X Remove protective film from surface of RESM20.
X Clean shaft taper and internal taper of RESM20 as
recommended in 'Storage and handling' on page
X Insert the first screws:
- For RESM20 rings with 6, 9 or 18 mounting holes,
use 3 equally spaced M3 screws.
- For RESM20 rings with 12, 16 or 20 mounting holes,
use 4 equally spaced M3 screws.
NOTES:
X Do not lubricate screws.
X Do not use a thread locking compound.
X Recommended screw type M3 × 0.5 and must
comply with: ISO 4762/DIN 912 grade 10.9 minimum/
ANSI B18.3.1M.
X Minimum thread engagement 6 mm.
X Insert the screws so that the RESM20 is loosely
connected to the shaft, then roughly align the ring by eye
and touch.
X Lightly tighten the screws. Use a Dial Test Indicator (DTI)
to check the radial displacement at the
screw locations.
NOTE: Disregard the radial displacement between the
screw locations.
DTI
Use a non-contact or low force <0.04 N DTI with
ruby ball to ensure scale surface is not marked.
X Adjust the screws to reduce the range of radial displacement. When adjusting, identify the screw
location with the lowest radial displacement and tighten that screw, aiming for the average of the highest
and lowest indicator readings.
X Repeat this process until the DTI readings are within ±5 µm at the screw locations.
NOTE: It may be necessary to loosen screws whilst tightening other screws.
5.
Step 3
Original instructions
NOTE: At this stage, the screws
should only be lightly tightened
(less than 0.5 Nm) to allow
further final adjustment.
X Insert the next screws:
- For RESM20 rings with 6, 9 or 12 mounting holes,
insert all the remaining M3 screws.
- For RESM20 rings with 16 mounting holes, insert
3 equally spaced M3 screws.
- For RESM20 rings with 18 mounting holes, insert
6 equally spaced M3 screws.
- For RESM20 rings with 20 mounting holes, insert
8 equally spaced M3 screws (in four groups of two)
between existing screws.
X As described in Step 2, adjust all the screws inserted thus
far, so that the radial displacement at each screw location
is within ±5 µm.
X Again, at this stage, the screws should only be lightly
tightened (less than 0.5 Nm).
NOTE: You may notice that the torque required to achieve
the radial displacement tolerance will be slightly higher
during Step 3 than during Step 2. This is normal.
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