5 FT 70 en
11
4.9
Assembly
4.9.1
FC series
Lubricate the seat threads with Molykote 321R or a
similar substance.
Screw the seat loosely to the end of the body
threads.
Place the valve so that the flange rests on a soft base
and the threaded flow port is pointing downwards.
Push the lower bearing (16) into place using the
stem as help. Avoid forcing it.
Valves manufactured before January 1, 1995:
Slip the upper bearing (15) on the stem.
Valves manufactured after January 1, 1995:
(Mark "A" in the ID plate field MOD):
Slip the upper bearing (15) through the flow port
into body counterbore.
Place the plug (3) into the body on the seat, in the
closed position. Make sure that the plug is in the cor-
rect position: the splines must face the lower bearing
(sizes DN 25 and 50 have splines facing both the
upper and lower bearings) and the position of the
contour of the plug with respect to the body must
be as shown in the exploded view.
Slip the stem through the plug. One tooth has been
removed from the stem, so there is only one way of
fitting the stem into the plug. Keep the plug in place
by pressing it against the seat; the seat should not be
screwed in too deep. Do not force the stem through
the plug. After you have assembled the valve, you
will see the plug position from the marking at the
end of the stem or from markings on the side of the
stem.
Slip the thrust bearings (70) on the stem.
Place a new bonnet seal (66) into the bonnet (8) and
assemble the bonnet. Fasten the lubricated hexagon
nuts (17) onto the studs (13) and tighten them alter-
nately. See Table 1.
Push the packings/V-ring set (69) onto the stem and
on into the packing recess. Take care not to damage
the V-rings in the stem splines. Use the gland fol-
lower (9) to push the packings all the way down.
Install the gland follower (9). Tighten the hexagon
nuts (18) onto the studs (14) by hand.
Install the bracket (29), lubricate the screws (30) and
tighten them. See Table 1.
Turn the valve so that it rests on the other flange (the
threaded flow port pointing upwards).
Centre the plug (3) relative to the seat (7) by turning
the stem with the hand lever.
Screw the seat (7) against the plug by hand.
Install the back seal (63) into the insert (2).
Screw the insert (2) onto the threads of the seat (7).
Keep the seat (7) in place with the help of the plug
(3) by turning the stem with the hand lever using
torque specified on Table 11. At the same time
tighten the insert (2) with a spanner wrench using
torque specified on Table 4.
A light can be shined behind the plug to determine
the best possible alignment. The best alignment is
when the least amount of light can be seen between
the plug and seat.
Lock the insert by hitting it with a nail punch to
make juts over two of the four available notches on
the body.
Tighten the gland nuts (18) 1.5 to 2 turns using a
wrench. The packings are damaged if they are tight-
ened too much.
4.9.2
FL series
Assemble the back seal (6) into the seat (7). Push the
support ring (8) on the seat (6) following with the
spring (5). Push these parts as a package in the body
cavity. Note that part (4) is factory locked to the body
and should not have been removed.
Put the lower bearing (17) on the shaft (12) and the
upper bearing (17) in the body cavity. Check that the
pin holes in the ball (3) have not been damaged dur-
ing dismantling.
Assemble the ball (3) in the body and the shafts
(11,12) through the shaft holes so that the pin holes
are parellel with each other. Press the pins into the
ball/shaft holes and lock them with a centre punch.
See Fig. 19.
Assemble the seal (19), blind flange (10) and the
hexagon screws (26) and tighten.
Assemble and tighten the studs (24), insert packing
rings (20), gland (9), retainer plates (30), disc spring
sets (32) and the nuts (25) and tighten.
Insert the key (13) in the drive shaft (11) keyway.
4.10
FL low capacity valve
4.10.1 Constructional differences
A version for low capacity control use is available. This valve
differs from the rest of Finetrol line as follows: The plug has
been replaced with a ball and the seat with an element con-
sisting of a seat, a bushing and graphite seals. The eccen-
tricity of the construction has been corrected by means of
the seat design. The tightness is based on precompression
of the graphite seals, boosted by the pressure of the
medium. The valve is bidirection-ally tight but the recom-
mended mounting position is flow to close (FTC).
A normal version can be converted to a low capacity ver-
sion by using part nos. (3), (7), (35) and (64).
Table 4
Insert torques, graphite and PTFE back seal
Size
Graphite back seal
PTFE back seal
DN
NPS
Nm
ft lb
Nm
ft lb
25
1
30
22
20
15
40
1.5
70
52
50
37
50
2
120
89
90
66
80
3
330
244
230
170
100
4
500
370
350
260
150
6
900
666
630
465
200
8
2400
1776
1700
1250
250
10
3200
2368
2200
1650
NOTE:
Do not rotate the plug in the valve body!
Damage to the seat may result.
