November 2022
Installation, Operation and Maintenance Manual
MAC050515 EN Rev. 0
16
Assembly Instructions
Section 10: Assembly Instructions
10.4
Piston Assembly
10.4.1
Clockwise Rotation
(Pistons moving inwards, refer to Figure 5 [a]).
1.
Align the pinion by lining up the center of the NAMUR slot in the top of the pinion
with the single dot on the body. The top of the pinion is marked with a single
identification dot to indicate the correct orientation of the stop faces.
2.
Lightly grease all piston grooves, gear form and piston O-Rings (4) and fit the
O-Ring (4) and wear ring (3) to the piston.
3.
Fit the bearing block (10) to the back of the piston.
4.
Grease the actuator body bore.
5.
Insert the pistons into the bore, ensuring the piston racks line up with the
pinion gear. (The part number in the front face of the piston must be lined up
parallel to the pinion).
6.
Push both pistons together until they are both in contact with the pinion, so that
when the pinion is rotated clockwise the pistons are drawn together. When the
pistons are together and the racks are correctly engaged with the pinion, the top
pinion drive flats should be at right angles to the axis of the body.
10.4.2
Counterclockwise Rotation
(Pistons moving inwards, refer to Figure 5 [b]).
Align the NAMUR slot in the top of the pinion with the two dots on the body and assemble
the pistons so that the pinion rotates counterclockwise as the pistons are drawn together.
10.5
Travel Stop Assembly
(Refer to Figure 1)
1.
With the pistons together, screw in the CLOSING (cast identity number 2) travel
stop (22), complete with locking nut (24) and thread seal (23), until it comes into
contact with the pinion stop face.
2.
Rotate the pinion through 90ø only, driving the pistons apart and screw in the
OPENING (cast identity number 1) travel stop (22), complete with locking nut and
thread seal, until it comes into contact with the pinion stop face. For individual
position requirements, see Section 4.
