4 GV 71 en
7
4.4
Replacing the trim and body
reassembly
Make sure the valve is not pressurised.
Remove the actuator from the valve stem according
to the instructions given in the actuator manual and
Section 6.
Loosen the hexagon nuts (18) slightly.
Remove the hexagon nuts (17).
Remove the bonnet (8)
Remove the plug unit (2) and
the retainer (10).
Remove the body gasket (65), seat ring (7), seat gas-
ket (63)
Remove the hexagon nuts (18), gland flange (9b)
and packing gland (9a).
Remove the old packing rings (69) (and optional lan-
tern ring (21))
Clean the body gasket surface.
Insert a new seat gasket (63) and the seat ring (7)
into the body.
Install the plug set (2*) with the retainer (10) very
carefully.
Insert the body gasket (65).
Mount the bonnet on the body carefully maintaining
alignment with the plug and the stem and with the
retainer in the closed position, so that the arrow on
the body and on the bonnet point in the same direc-
tion.
Insert the bonnet nuts into stud bolts and slightly
fasten the stud nuts.
Insert the packing according to above 4.3
Tighten hexagon nuts (17) until plug and seat con-
tact is obtained with proper bolt torque.
Adjust and tighten the gland nuts finally.
NOTE:
The trim set consists of the seat, plug and stem, retainer
and gaskets (for seat and body).
CAUTION:
Do not reuse the spiral wound gaskets (63 & 65), this is
need to be replace each time the valve is disassemb-
led.
NOTE:
If the valve have excess leakage, the plug and seating sur-
face need lapping and cleaning.
CAUTION:
Do not excessively tighten stud nuts at this time.
NOTE:
Guide Bushing Removal
The Guide Bushing (4) is a press and tag welded fit into the
retainer and does not normally necessary replacement.
If need, it may be machined out. When machining the
bushing out, care must be maintain proper dimensions
and tolerances.
CAUTION:
The all related parts (seat ring, retainer, plug & stem,
bonnet) must be properly aligned in the body.
Fig. 8
Conventional Trim
Fig. 9
Tendril 1-Stage Trim
