User Manual

9
MAINTENANCE (Cont'd)
TRAVELING NUT ACTUATOR MAINTENANCE: A
typical traveling nut actuator is shown in Figure 11
and consists of a threaded nut (12) which travels
back and forth on a threaded stem (14). The stem is
lubricated with EP2 grease in a cast iron housing
(1). The nut, in turn, drives a slotted lever (4)
through 90 degrees of travel. The lever (4) drives
the valve shaft with a square key. The rotation of the
shaft is displayed by the top indicator (19). The full
open and closed positions are controlled by the stop
nuts (6). The stop nuts can be adjusted by
pounding out the pin (7) with a drift punch and
rotating the stop nut ½ turn. The gear box is factory
lubricated and sealed. No regular maintenance is
required. If difficult operation is observed, the cover
can be removed and the unit inspected for wear. All
moving parts should be coated with grease. The
grease should have an even and smooth
consistency. If needed, coat all moving parts with
an EP-2 grease such as Mobil Mobilux EP2. Buried
units should be packed 100% with grease.
FIGURE 11. TRAVELING NUT ACTUATOR
TABLE 5. TRAVELING NUT ACTUATOR PARTS
ITEM DESCRIPTION MATERIAL
1 Housing Cast Iron
2 Housing Cover Cast Iron
3 Cover Bolt Steel
4 Lever Ductile Iron
5 Plug Steel
6 Stop Nut Steel
7 Stop Nut Pin Steel
8 End Cap Cast Iron
9 End Cap O-ring Buna-N
10 Stem Collar Bronze
11 Collar Pin Steel
12 Crosshead Bronze
13 Shaft O-ring Buna-N
14 Stem Alloy Steel
15 End Cap Bolts Steel
16 Handwheel Steel
17 Pin Steel
18 Indicator Bolt Steel
19 Indicator Aluminum
20 Needle Bearings Steel
21 Bearing Race Steel
22 Shaft Bearing Teflon/Fiberglass
30 Gasket Composition Rubber
31 Indicator Extension Steel
32 Extension Pin Steel
33 Operating Nut Cast Iron
34 Chainwheel Kit Ductile Iron
35 Grease EP-2