For output drive type A (figure B-1), the internal thread of the stem nut must
match the thread of the valve stem. If not ordered explicitly with thread, the
stem nut is unbored or with pilot bore when delivered. For finish machining
of stem nut refer to section below within this clause.
.
Check whether bore and keyway match the input shaft of valve/ gearbox.
.
Thoroughly degrease mounting faces at multi-turn actuator and valve/
gearbox.
.
Apply a small quantity of grease to input shaft of valve/ gearbox.
.
Place actuator on valve/ gearbox and fasten. Fasten bolts (quality min. 8.8,
refer to table 2) evenly crosswise.
Finish machining of stem nut (output drive type A):
Refer to figure B-1 and exploded view on page 30.
.
Remove 4 bolts (4.09) and take off the complete mounting flange (4.11)
from the actuator.
.
Loosen grub screw (44.01).
.
Completely unfasten bearing lock nut (4.13) with pin wrench.
.
Remove stem nut (4.12) together with the upper needle bearing (44.03)
and the bearing races (44.04). Protect the removed needle bearing, the
bearing races, and the output drive flange with the other bearing from
chips and dirt.
.
Drill and bore stem nut and cut thread.
When fixing in the chuck, make sure stem nut runs true!
.
Clean the machined stem nut and re-insert it into the mounting flange.
.
Grease lower bearing race (44.04), needle bearing (44.03), and upper
bearing race, then reposition them.
Needle bearing and bearing races must be free from impuri-
ties! If necessary, clean them with petroleum or a similar
solvent.
8
Multi-turn actuators SAI 6 – SAI 100 / SARI 6 – SARI 100
for valve automation Inside Containment in nuclear power plants
Operation instructions
Strength class 8.8
T
A
(Nm)
M 6
1
1
M 8
25
M 10
5
1
M 12
87
M 16
2
14
Table 2: Fastening torque for bolts
Figure B-1: Output drive A
4.13
4.09
44.01
44.03
44.04
44.02
4.12
4.11
M
20
431
