Leslie Controls CONTROL VALVES SINGLE PORTED DOS - Manual (Page 5)

5
Removing Actuator from Valve
Body Assembly
Direct Acting Actuator:
Loosen valve plug stem nut (29). Use wrench on
flats of valve plug stem and turn valve plug stem
out of actuator stem threads until it is
disengaged. (In large control valves, support
valve plug stem to prevent valve plug from
suddenly falling downward as valve plug stem
clears actuator stem). Take travel indicator off
valve plug stem.
Remove capscrews (39) holding actuator to
bonnet and lift actuator off bonnet.
Reverse Acting Actuator:
Insert lock rod (attached to yoke) through yoke
and stem, loosen valve plug stem nut, then
follow direct acting actuator procedure.
Single Ported Unbalanced Types
– DL, DOS Types
(See Fig. 3 and 4)
Remove nut (29) from valve plug stem.
Disassemble bonnet bolts/nuts (45/42). Lift
bonnet, valve plug assembly and bonnet gasket
(44) off valve body. Loosen and remove bottom
cap (flange) (48) and gasket (47) where
applicable.
Disassemble packing flange
bolts/studs (37), packing flange (36) and packing
follower (38) from bonnet. Clean out packing
box.
Figure 3 - Cage Trim (DOS Type)
Valves Fitted with Cage Type
Trim (O in Class)
(See Fig.3)
Trim components are: Seat retaining guide/cage
(48), seat ring/insert (51) and seat ring/insert
gasket (50). Body gasket (47), seat retaining
guide/cage (48), valve plug guide and throttling
sector will come out along with valve plug.
Disassemble parts when removing valve plug
from bonnet.
To remove seat ring/insert, place tapered wooden
dowel into seat ring/insert and lift out seat
ring/insert. Seat ring/insert gasket will follow.
(see Fig. 4)
Figure 4 - Single Ported Control Valve Body
Assmebly (Actuator Removed)
Replacing Seat Ring(s)/Inserts
(Threaded Ring Only)
To remove threaded seat ring use seat ring
wrench see Fig. 5.