Valve disassembly, Maintenance, Packing replacement – Jordan Valve Mark 78 Series – Globe Style Control Valve User Manual

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3. After packing is installed, assemble packing follower

(11), packing nut (15) to bonnet (4).

Valve Disassembly

1. Close inlet and outlet stop valves. Operate system by-

pass if necessary.

2. Following instructions according to valve action:
3a. Direct Acting Actuator (ATC): shut off operating me-

dium and relieve pressure from diaphragm by dis-
connecting tubing at diaphragm case. To remove the
actuator from the valve body assembly: loosen the
two stem nuts (28) and move them together with the
travel indicator (12) down the stem (9). Lock the nuts
together and, using a wrench on these nuts, turn the
valve stem out of the actuator stem (17) threads until
it disengages. Loosen and remove the packing nut
(15) and lock ring (32) and lift the actuator assembly
from the bonnet (4).

3b. Reverse Acting Actuator (ATO): apply air pressure to

actuator to lift plug off of seat. To remove the actuator
from the valve body assembly: loosen the two stem
nuts (28) and move them together with the travel indi-
cator (12) down the stem (9). Lock the nuts together
and, using a wrench on these nuts, turn the valve
stem out of the actuator stem (17) threads until it dis-
engages. Loosen and remove the packing nut (15)
and lock ring (32) and lift the actuator assembly from
the bonnet (4).

4. Remove the body/bonnet bolts (6) and lockwashers

(8).

5. Remove bonnet (4), o-ring (29), compressor (5) and

cage (2) from the body (1).

6. Remove support washer (42) [on soft seated valves

1-1/2” size only], seal (41) [soft seated valves only],
seat (3), and seat o-ring (30) from the body.

7. Remove the two stem nuts (28) and travel indicator

(12) from the stem (9).

8. Remove plug/stem (9) from the bonnet (4).
9. Remove packing follower (11) and packing (13), re-

tainer (14), and spring (10).

10. Cleaning: clean all parts with an approved, non-res-

idue-forming solvent. Remove encrusted materials
with crocus or very mild aluminum oxide cloth. Clean
packing box thoroughly.

11. Inspect all parts including plug, seal and seat. Re-

place any badly worn or damaged parts.

12. Replacing Seats (Hard Seated Valves Only): if seat is

badly worn or damaged, it should be replaced. Very
minor cuts on the seating surface, however, may be
lapped out. NEVER lap to the extent that the valve
plug becomes grooved.

13. Lapping in Valve Plug & Seat Ring: replace valve plug

(9) in bonnet (4). Apply superfine lapping compound
to valve plug seating surface at several points. Re-
place seat o-ring (30) and seat (3) in body (1). Re-
assemble bonnet (4) to body (1). Use stem to align
seat to plug in the body. Lap valve plug and seat ring

to start flow through the control valve. Increase flow
gradually by slowly opening the inlet shutoff valve. Do
not fully open the inlet valve until you are sure that
the controller and control valve have control of the
system. Usually, the handwheel on the inlet valve will
turn freely when this point is reached.

4. To shut off the line fluid, close the inlet shut-off valve

first, then the outlet shut-off valves.

Maintenance

To reduce maintenance time, refer to proper figure
and follow steps indicated below for applicable main-
tenance operation.

Proposed Maintenance

Procedure

Follow Steps...

Renewing stem packing

Packing Replacement

Valve disassembly, inspecting

parts, replacing plug or seat ring

Valve Disassembly

Valve Reassembly

Valve Reassembly

Actuator spring preload

adjustment

Actuator Spring

Preload Adjustment

Actuator maintenance

Actuator Maintenance

Changing valve action

Reversing Action

Routine maintenance should be expected due to nor-
mal wear and tear, damage from external sources or de-
bris. The regulator components, especially the moving
and sealing parts, should be inspected periodically and
replaced as necessary. Frequency of inspection/replace-
ment depends upon severity of conditions, but may also
be required by local/state/federal law or industry stan-
dards.

Packing Replacement

Renew valve plug stem packing if control valve has been
in service beyond normal maintenance, and packing
shows signs of wear. Wear will be indicated by leakage
which cannot be corrected by minor tightening of pack-
ing flange.

An additional packing ring can be installed to overcome
minor leakage without dismantling the control valve or
breaking valve plug connection.

1. Disassemble control valve as far as necessary for the

work required (see “Valve Disassembly”). Remove
packing. Clean valve plug stem (9) and packing box
thoroughly. Polish valve plug stem (9) with crocus
cloth. Use approved non-residue-forming solvent for
cleaning. Wipe dry with clean cloth.

2. Insert a new set of packing (13) in packing box. Press

each ring down in place with a tube as it is installed.

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