Installation, Operation and Maintenance Manual
Butterfly Valves Type 75, 75D Pneumatic Actuated Type TW 20
1) Before starting assembly, silicone grease (equivalent to Toray
Silicone HVG) should be spread on the disc O-ring (A) , (B)
 and stem O-ring (C) .
2) The procedure of the assembly is the almost reverse of its
However, to insert seat  with the disc  into the body , set
the disc  with half-opened position. Press outer rim of seat
 into inside of the body , keeping stem holes straight.
(Make sure that stem holes of the seat  are in alignment with
the stem holes of the body .)
3) Make sure that the disc  fits seat  well.
4) Check to ensure that travel indicator shows correct position of fully open or close.
5) Fully open or close the valve by air operation. (Refer to page16)
*In case that the travel indicator shows incorrect position of fully open or close, adjust it according to “18 Stopper
(18) Stopper adjustment procedure
● Spanner wrench
* Don’t supply air during manual operation.
(When air is supplied during the manual operation, injury may occur.)
1) Stop the air supply, and open the bypass valve to exhaust
the air in actuator.
2) Attach the spanner wrench or the hexagon wrench to
stopper, and loosen the locking nut with the spanner
* Don’t damage the seal washer. (Otherwise, the air may leak.)
3) Turn the stopper with the spanner wrench or the
hexagon wrench to adjusting direction.
*Avoid excessive tightening. (Otherwise, the air may leak.)
Direction Clock wise Counter
Open side Smaller Larger
Close side Larger Smaller
4) Close the bypass valve, and supply the air to the actuator. Operate the valve with air to make sure that opening
degree is adjusted correctly.