Flowserve NAF-Turnex pneumatic actuators User Manual

Page 7

Sizes 1-3

1. Make sure that all parts have been thoroughly cleaned.

Wipe clean the cylinders (1, 16), bearing surfaces of

the lever (21), and other sliding surfaces.

2. If the linkage mechanism (Fig. 1) has been

dismantled, re-assemble it. Fit the links (12-14) to the

coupling pins (31). Then ﬁt the circlips (11) and

assemble the links with the lever (21) and pins (23).

Finally, ﬁt the circlips (22).

3. Grease the bearings (38) and O-rings (37). Fit them

into the housing (30) and cover (29), and to the

lever (21). Fit the linkage mechanism into the housing.

Make sure that the lever is ﬁtted with the milled driver

grooves facing upwards (towards the cover 29),

and that the mounting plate (33) on the coupling faces

outwards towards the window (35).

4. Rub a thin ﬁlm of grease onto the surface ot the piston

rod (26). Carefully push the piston rod past the piston

rod seal (27), through the bearing (28), coupling (31)

and out through the opposite bearing and seal.

N.B. The location of the hole in the piston rod is not

symmetrical. The side of the piston rod which is

longer (from the hole to the end) should be located on

side A as shown in Fig. 19.1.

5. Coat the lips of the pistons (25) with a thin ﬁlm of

grease, and make sure that the groove between the

lips is ﬁlled with grease. See Fig. 9. Fit the pistons to

the piston rod (26), with the rubber-coated side facing

the nut. Apply locking compound to the piston rod

thread. Fit the washer (24.1) and nut (24). After the

pistons have been ﬁtted, tighten the nuts

simultaneously to the torque speciﬁed in Table 1.

6. Align the hole in the piston rod (26) with the hole in

the coupling (31). Apply some anti-galling agent, such

as Molycote, to the unthreaded part of the pin (10),

and then ﬁt the pin into the coupling.
The pin should enter easily into the hole. Never

use force. It may sometimes be necessary to rotate

the piston rod through half a turn. Tighten the pin to

the torque speciﬁed in Table 1.
7. Fit all the tie rods (2).

8. Grease the O-rings (3, 17), and ﬁt two of the O-rings

(3) and both O-rings (17).

Fig. 9. Lubrication of the piston

Grease

9. Apply a thin ﬁlm of grease to the surfaces of the

cylinders (1, 16) and use a clean piece of lint-free

linen cloth to work the grease into the whole of the

sliding surface. Carefully push the cylinders onto the

pistons.

One actuator size 1, the cylinders on sides A and B

are different.

10. Fit the O-rings into the end covers (4) and ﬁt the

covers to the cylinders. Then ﬁt the washer (5) and

nuts (6) to the tie rods and tighten the nuts in

diagonally opposite pairs to the torque speciﬁed in

Table 1.

11. Fit the cover (29). Apply a little locking compound to

the threads of the screws (18), and tighten the screws

to the torque speciﬁed in Table 1.

12. Adjust the end-stop bolts (9) to the required end

positions.

Sizes 4-5

1. Make sure that all parts have been thoroughly cleaned.

Wipe clean the cylinders (35), bearing surfaces of the

lever (6), and other sliding surfaces.

2. If the linkage mechanism (Fig. 1) has been

dismantled, re-assemble it. Fit the links (8A) to the

coupling pins (25). Then ﬁt the circlips (19) and

assemble the links with the lever (6) and pins (9A).

Finally, ﬁt the locking clips (10A).

3. Grease the bearings (3, 4, 15 and 16) and O-rings (7,

17). Fit them into the housing (1) and cover (2), and

to the lever (6). Fit the linkage mechanism into the

housing. Make sure that the lever is ﬁtted with the

milled driver grooves facing upwards

(towards the cover 2).

4. Rub a thin ﬁlm of grease onto the piston rod (26).

Carefully push the piston rod past the piston rod seal

(42), through the bearing (11), the coupling (25 and

27 and the opened-up locking clip 26) and out

through the opposite bearing and seal.

5. Coat the faced O-ring (34) on the pistons (32) with a

thin ﬁlm of grease. Fit the piston to the piston rod

(26) with the chamfered recess side towards

the nut. Apply some locking compound to the piston

rod thread. Fit the nut (36). After the pistons have

been ﬁtted, tighten the nuts simultaneously to

the torque speciﬁed in Table 2.

6. Guide the circlip into the piston rod groove and lock it.

Tighten the two halves of the coupling (25) and (27),

using the screws (14).

Table 2. Tightening torques, Nm, for the bolts and nuts of the actuator.

Part

Actuator size

Piston rod nut (36)

400 800

Bolt (12)

Locking screw (45)

Stud (49)