Marwin Valve 3000 Series Fire Safe Ball Valve - Manual (Page 3)

replaced by qualified personnel following the
instructions of this manual.
For further information, please refer to 3. SPARE
PARTS LIST .
Valve Disassembly
A. To inspect and/or Replace Body Seals, Seats,
Packing & Ball
Reference cross section for part identification
Valve must be in the open position. 1.
Remove valve from line. 2.
Remove bolts (10) securing end caps and sepa- 3.
rate from body (center section) (1).
If end caps (2) have not been removed from pipe- 4.
line, it will be necessary to spread the pipe slightly
to remove center section (1).
Turn the stem to close the valve and remove ball 5.
(3), seats (4), body seals (6) and second body
seals (7). Be careful not to damage the ball.
Remove the handle nut (16), handle (18), stem nut 6.
(16), Belleville washers (15), gland (14), and pack-
ing (13).
Push the stem (5) into the body (1). Remove o-ring 7.
(17) and thrust washer (12) from stem.
B. Inspection and Replacement
With the valve completely disassembled, clean and
examine all components.
The surface of the ball should be free from any de- 1.
fect. If any are found, the ball should be replaced.
Using a defective ball will be extremely detrimental
to valve performance.
Seats. Replacement of seats is recommended. 2.
Stem seals and body seals. Should be discarded 3.
and replaced.
Remaining components of the valve. After clean- 4.
ing, carefully examine for wear, corrosion and
mechanical damage. Replace all defective parts.
Clean inside of body and stem housing. Light 5.
grease, compatible with line fluid, can be used on
ball, seals and stem surface.
Note: A spare parts list is available for this valve.
Please refer to explosion view below for identifica-
tion. Please specify specific valve number to ensure
proper parts are ordered. Marwin Valve does not take
responsibility for incorrectly ordered spare parts.
Re-Assembly
A. Stem
Replace thrust washer (12) and O-Ring (17) then 1.
insert the stem from inside of body.
Install stem packing (13), gland (14), Belleville 2.
washers (15), stem nut (16), and tighten until snug,
then one-half turn. To avoid rotation of stem, insert
a non-marking object thru the ID of the ball.
Install lockwasher (8), handle (18), and handle nut 3.
(16) then tighten.
B. Ball, Seats, and Seals
Place the stem (5) in closed position and insert the 1.
ball (3), aligning groove in ball with bottom of stem.
Position the ball in the open position then insert a 2.
seat (4), body seal (6), secondary body seal (7),
and end cap (2) on each side of body.
Tighten bolts to recommended torque values using 3.
an alternating/opposing pattern with no more than
1/4 turn on each bolt before alternating.
Testing
After completing the reassembly, check that valve 1.
operates smoothly by opening and closing valve
several times.
If entire valve was removed from line and if facili- 2.
ties area available, test the ball valve to appropri-
ate specifications.
Troubleshooting
A. Stem Leakage
Leakage in the stem packing area may be eliminat- 1.
ed by increasing the torque on the stem nut (16) in
one-quarter turn increments. Some size valves may
require a thin wall socket (or turned down equiva-
lent). If leakage persists, replace stem packing
(13) and stem o-ring (17).
B. Body Seal Leakage
Check the torque of the body bolts (10) according 1.
to Torque Table. Replace body seals (6 & 7) if leak-
age persists.
C. In Line or Seat Leakage
Check to be sure valve is in fully closed position. If 1.
leakage persists, the valve must be disassembled
and damaged parts replaced.
12
4
7
13
6
17
Spare Parts List
Item # Quantity Part Name
13 2 Packing
12 2 Thrust Washer
17 1 O-Ring Stem
4 2 Seat
6 2 Body Seal
7 2 Secondary Body Seal
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