Marwin Valve CV3000 Series Characterized Insert Control Valve - Manual (Page 3)

However, when necessary, ball or seats can be
replaced by qualified personnel following the
instructions of this manual.
3. For further information, please refer to SPARE
PARTS LIST .
Valve Disassembly
A. To inspect and/or Replace Body Seals, Seats,
Packing & Ball
Reference cross section for part identification
1. Valve must be in the open position.
2. Remove valve from line (with end caps if possible).
3. Remove bolts (12) securing the end caps (2) from
body (1).
4. If end caps (2) have not been removed from pipe-
line, it will be necessary to spread the pipe slightly
to remove body (1).
5. Close the valve and remove ball (3), seats (4),
body seals (6), secondary body seals (7), charac-
terized plate (24), and index pin (25).
6. Remove nut (22), lockwasher (8), second nut (22),
Belleville washers (21), stem gland (20), and pack-
ing (18).
7. Push the stem (5) into the body (1). Remove o-ring
(23) and thrust washer (17) from stem.
B. Inspection and Replacement
With the valve completely disassembled, clean and
examine all components.
1. The surface of the ball should be free from any de-
fect. If any are found, the ball should be replaced.
Using a defective ball will be extremely detrimental
to valve performance.
2. Seats. Replacement of seats is recommended.
3. Stem seals and body seals. Should be discarded
and replaced.
4. Remaining components of the valve. After clean-
ing, carefully examine for wear, corrosion and
mechanical damage. Replace all defective parts.
5. Clean inside of body and stem housing. Light
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
1. Replace thrust washer (17) and O-Ring (23) lubri-
cate, then insert the stem from inside of body.
2. Install stem packing (18), gland (20), Belleville
washers (21), and stem nut (22) and tighten until
snug, then one-half turn. Install lockwasher (8) and
second stem nut (22). To avoid rotation of stem,
insert a non-marking object thru the ID of the ball.
B. Ball, Seats, and Seals
1. Place the stem (5) in closed position and insert the
ball (3), aligning groove in ball with bottom of stem.
2. Position the ball in the open position.
Note: For steps 3 through 6, the downstream
(DS) end of the body is indicated by the head
of the flow arrow on the body, and the upstream
(US) end by the tail.
3. Insert a body seal (6) and secondary body seal (7)
on the downstream (DS) end of the body. Insert a
seat (4) in the DS end cap (2A), and insert the DS
cap on the DS end of the body (1).
4. Install and hand tighten the DS body bolts (12).
5. With the ball still in the open position, insert a
body seal (6) and secondary body seal (7) on the
upstream (US) end of the body. Insert the index pin
(25) in the locating hole in the US end cap (2B),
and insert the characterized plate (24) in the US
end cap, so the hole or slot of the plate locates on
the pin. Insert a seat (4) into the US end cap over
the plate, and insert the US cap on the US end of
the body (1).
6. Install and hand tighten the US body bolts (12).
7. Tighten bolts to recommended torque values using
an alternating / opposing pattern with no more than
1/4 turn on each bolt before alternating.
Testing
1. After completing the reassembly, check that valve
operates smoothly by opening and closing valve
several times.
2. If entire valve was removed from line and if facili-
ties area available, test the ball valve to appropri-
ate specifications.
17
4
23 18
6
Spare Parts List
Item # Quantity Part Name
18 2 Packing Ring
17 1 Thrust Washer
23 1 "O"-Ring Stem
4 2 Seat
6 2 Body Seal
7 2 Secondary Body Seal
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