Fisher-Rosemount Design CV500, Инструкция по эксплуатации

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Design CV500
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Table 6. Data for Tapped Holes on Valve Shaft
SHAFT DIAMETER
THREAD
VALVE
SIZE
Through
Valve
At Spline
End
Through
Valve
At Spline
End
THREAD
SIZE,
UNC
SIZE
mm Inches
UNC
3
25.4 25.4 1.00 1.00 3/8-16
3
25.4 19.1 1.00 0.75 5/16-18
4 31.8 31.8 1.25 1.25 3/8-16
6
38.1 38.1 1.50 1.50 1/2-13
6
38.1 31.8 1.50 1.25 3/8-16
8 38.1 38.1 1.50 1.50 1/2-13
10 44.5 44.5 1.75 1.75 1/2-13
12
53.8 53.8 2.12 2.12
3/4 10 12
53.8 50.8 2.12 2.00
3/4-10
8. For 3 through 8-inch sizes, Refer to figure 8. The
expansion pin (key 9) and the taper pin (key 10) inside
of it are holding the ball in position on the drive shaft.
Find the larger hole in the ball ear where these pins
enter the ear. On the opposite side of the ear is a
smaller hole where the chamfered end of the
expansion pin rests on the inner lip of the hole.
9. For 10 and 12-inch sizes, drive out the groove pin
that secures the ball to the drive shaft. Remove the
groove pin from the ball ear in the direction shown in
figure 8.
WARNING
To avoid personal injury or damage to
tools, valve parts, or other items
resulting from the ball (key 2) falling
from the valve body, support the ball to
prevent it from falling as the drive shaft
(key 3) is being removed.
10. Pull the drive shaft (key 3) from the valve body. If
the shaft cannot be removed by hand, attach a slide
hammer or similar tool to the spline end of the shaft
that was attached to the actuator. If the shaft has a
tapped hole at the spline end of the shaft; refer to
table 6 for thread sizes.
11. Remove the ball (key 2), and thrust washers
(key 12) from the valve body.
Note
For 3 through 8-inch sizes, two shaft
bearings (key 6) are located inside the
valve body on either side of the ball.
Only one of these two bearings is
identified by key 6. The other bearing is
located along the drive shaft on the
other side of the V-notch ball.
Figure 8. Taper and Expansion Pin Removal from
Ball and Drive Shaft
E0575 IL
DRIVE PINS OUT
FROM THIS END
(SMALLER HOLE)
SLASH MARK ON SPLINED
END OF SHAFT
For 10 and 12-inch sizes, there are two
shaft bearings. One is identified as key
6, and the other is identified as key 42.
12. If the shaft bearings are to be replaced, remove
packing (key 13).
13. If the bearing closest to the packing (key 6 on 3
through 8-inch sizes and key 42 on 10 and 12-inch
sizes) requires replacement and cannot be removed
by hand, press it out using a ram with dimensions as
given in figure 9. The ram has a smaller diameter than
the bearing stop (key 7) so the bearing stop need not
be removed when pressing out the bearing on the
drive shaft. Insert the ram through the packing box and
press the bearing into the valve body cavity. Take care
not to move the bearing stop when pressing out the
bearing.
14. For 3 through 8-inch sizes, if the second bearing
(key 6) requires replacement and cannot be removed
by hand, use one of the following methods:
D
Knock or pry the bearing out, or
D
Use the valve drive shaft as a piston to drive the
bearing from the valve body. To accomplish this, install
the pipe plug (key 29). Fill the bearing bore with a
heavy grease and then insert the end of the shaft back
through the valve body and into the grease-filled
bearing. Protect the splined end of the shaft with, for
example, a block of wood; then strike the protected
end. When the shaft is struck, it will act as a piston,
pushing the grease into the bearing bore. The grease
will then force the bearing out of the bore and farther
along the shaft. Soon, the bearing will be positioned
for easy removal.