Fisher-Rosemount Design CV500, Инструкция по эксплуатации

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Design CV500
11
the shutoff surface of the seat ring, and the face seal
surface in the valve body.
A new retainer gasket (key 11) is required whenever
the retainer (key 5) is removed. Other parts that are in
good condition can be reused.
Disassembly
1. Isolate the control valve from the line pressure,
release pressure from both sides of the valve body,
and drain the process media from both sides of the
valve. If using a power actuator, also shut-off all
pressure lines to the power actuator, release all
pressure from the actuator. Use lock-out procedures to
be sure that the above measures stay in effect while
you work on the equipment.
2. Remove line bolting. Then, remove the control
valve from the pipeline and place the valve on a flat
surface with the retainer (key 5) facing up.
3. Rotate the drive shaft (key 3) to move the ball (key
2) into the open position.
Note
The retainer (key 5) was installed at
the factory using the torque listed in
figure 7.
4. Remove the retainer (key 5) by engaging the
retainer tool, attaching an impact wrench or other
suitable tool, and unscrewing the retainer. Inspect the
retainer. Place it on a protected, flat surface where the
threads and inner surface will not be contaminated or
damaged.
5. Remove the retainer gasket (key 11). Inspect the
gasket surface in the valve body.
6. Lift out the seat ring (key 4) and both face seals
(key 8). Inspect the parts and place them on a flat,
protected surface.
7. Inspect the shutoff surface of the V-notch ball. If it
is worn, nicked, or scratched, proceed to the
Replacing Ball, Shaft, and Bearings procedure. If the
parts are in good condition and do not require
replacement, continue to the Assembly procedure.
Assembly
WARNING
Seat ring installation requires that the
ball (key 2) remain in the open position.
To avoid personal injury or damage to
tools, valve parts, or other items
resulting from ball closing, prevent
against ball travel by using travel stops,
manual actuators, constant supply
pressure to a pneumatic actuator, or
other steps as appropriate. When
installing the seat ring, keep hands,
tools, and other objects out of the valve.
1. Apply enough supply pressure to the actuator to
open the ball, or take other steps to hold the ball open.
2. Clean the valve body, the retainer threads, the
retainer gasket surface, and the seat ring sealing
surface.
3. Using either face seals (key 8) in good condition or
new face seals, place one seal in the seat ring cavity
of the valve body.
Note
The seat ring (key 4) may have one or
two shutoff surfaces. The shutoff
surfaces are the narrow, rounded edges
of the seat ring bore. Inspect the seat
ring and locate the shutoff surfaces
before proceeding.
Make sure the ball (key 2) is open while you install the
seat ring (key 4) and retainer ring (key 5). Before
installing the seat ring, open the ball or plug.
Insert a screw driver, pry bar, or similar tool between
the lower ear of the ball and the valve body. Use the
pry to move the ball tightly against the thrust washer
and bearing stop (key 7) on the actuator side of the
valve. Keep the ball in that position until you finish
installing the seat ring.
4. Insert the seat ring into the seat ring cavity with the
correct shutoff surface facing the V-notch ball and
shaft. The seat ring will cover the face seal installed in
step 3.
5. Place the second face seal (key 8) on the seat ring
(key 4).
6. Apply Never-Seez Pure Nickel Special lubricant or
equivalent to the gasket surface in the valve body.
Install the gasket (key 11), while making certain that
the concave surface of the gasket is up (hump surface
of gasket down).
7. Apply Never-Seez Pure Nickel Special lubricant, or
equivalent, to the threads and bottom of the retainer
(key 5) only in the area that contacts the gasket.
Thread the retainer into the valve body.
8. Refer to figure 7. Find the correct retainer torque for
the valve size. With the appropriate tool, tighten the
retainer to the torque listed in figure 7.
9. A gap between the seat ring (key 4) and retainer
(key 5) allows the seat ring to self-center. Applying the
proper amount of torque during installation should
position the retainer and seat ring properly. Use a