10 1 D 71 en
Tightening the body joint bolts
❑ After fitting the ball and the body gasket, lift the
male body half (1) and the seat (7) onto the ball.
See Section 4.7.1.
❑ Check the correct alignment of the bonnet bore
with the body joint. Push the bonnet (8) onto the
stem.
❑ Lubricate the flange, neck and bonnet bolts and
screw them into position. If hexagon bolts are
used as flange bolts, it is easier to tighten them if
they are inserted from below so that the nuts can
be tightened from above the body joint flange.
❑ Put the bonnet (8) into its place. After tightening
the flange bolts loosen the bonnet bolts and
remove the bonnet.
❑ Tighten the flange bolts as indicated in Figure
18. Start from opposite the stem and first tighten
the bolts to torques that are 10 % of the values in
Table 1. Then tighten them to their final torques in
the same sequence.
❑ In valves up to DN 100 mm (4"), insert the neck
bolts before mounting the body halves. Center
them so that the distance from the nut’s outer
side to the bolt’s shoulder is equal at both ends.
Tighten the neck bolts after tightening the flange
bolts.
Tightening the bonnet bolts
❑ Remove any excessive body gasket from the
gland surface, for example with a screwdriver.
❑ Place the ring-shaped bonnet gasket (66) into
the bonnet shoulder. You can attach the gasket to
the bonnet for the duration of the installation with
small amounts of silicon grease.
❑ Place the bonnet onto the stem.
❑ Tighten the bonnet bolts as indicated by the tor-
ques in Table 1.
4.7.4 Gland packing, D2, D1F
❑ Install the new gaskets one by one by using the
gland. PTFE rings should be mounted so that the
breaks are at a 45 angle with respect to the flow
opening and at a 90 angle with respect to each
other. Graphite rings should be put into place
from the end of the stem. Make sure that there is
no burrs in the keyway, as it could damage the
gland packing.
❑ Put the gland into place.
❑ Turn the hexagon nuts on the studs and tighten
the gland packings while the valve is still unpres-
surized.
❑ Re-tighten the nuts as needed.
4.7.5 Gland packing, D1F_G
❑ Make sure the valve is not pressurized.
❑ Unfasten the nuts (25) and remove the disc spring
(TA-Luft) kits (43), the gland (9a), the retainer ring
(42) and the compression ring (9b).
❑ Remove old packing rings (20). Do not damage the
surfaces of the packing ring counterbore and shaft.
❑ Clean the gland and packing ring counterbore.
Install new set of packings. Slip the rings onto the
shaft. Ensure that there are no burrs in the key-
way groove which could damage the packing.
Position the cut ends of the graphite rings at a
90° angle to each other.
❑ Mount the compression ring.
❑ Slip the retainer ring on the shaft and push it
against the compression ring, see Fig. 19.
❑ Install the gland.
❑ Mount the disc spring kits.
❑ Place the nuts on the studs.
❑ Pre-compress the gland packing by tightening
the nuts with a tool until the disc springs have
Fig. 18 Tightening the body joint bolts
Table 1 Tightening torques
Thread Torque, Nm
5/16 UNC 25
3/8 UNC 45
1/2 UNC 100
5/8 UNC 200
3/4 UNC 350
7/8 UNC 500
1 UNC 700
1 1/4 8UN 1300
1 1/2 8UN 1600
1 3/4 8UN 1600
2 8UN 2500
2 1/4 8UN 3500
2 1/2 8UN 5000
2 3/4 8UN 6300
3 8UN 8400
NOTE: Tightening torques are for guideline only.
Consult with valve manufacturer.
Fig. 19. Mounting the retainer ring
To Next Page
Loading...
