Baker Hughes Masoneilan 4700P, Инструкция по эксплуатации

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Masoneilan 4700P/E & 4800P/E Positioners Manual | 39 © 2021 Baker Hughes Company. All rights reserved.
4. Select the desired cam lobe and replace cam (26) on cam shaft with low signal line of
desired lobe against cam follower. Ensure that the newly selected cam lobe is in the same
relative position as the lobe in Step 3.
5. Replace washer (27), lockwasher (51) and screw (28). Reduce pressure applied in Step
2 to zero (back off the handwheel if handwheel was used). Disconnect the independent
regulated air line to actuator and connect positioner output line. Connect supply pressure
and signal to positioner. Check zero and span adjustment. Refer to and “Span Adjustment”
on page 37.
Air to Close / Direct Acting Positioner
See Figure 18 (page 56) and Figure 19 (page 58).
1. Shut off supply pressure and signal to positioner. Valve is now open and cam (26) is at low
signal line on lobe.
2. With cam at low signal line remove screw (28), lockwasher (51) and washer (27). Note the
relative position of the cam lobe being changed and then remove the cam (26).
3. Select the desired cam lobe and replace cam (26) on cam shaft with low signal line of
desired lobe against cam follower. Ensure the newly selected cam lobe is in the same
relative position as the lobe noted in Step 2.
4. Replace washer (27), lockwasher (51) and screw (28). Check zero and span adjustment.
Refer to “Zero Adjustment” and “Span Adjustment” on page 37.
Air to Close / Reverse Acting Positioner
See Figure 18 .
1. Shut off supply pressure and signal to positioner. Valve is now open and cam (26) is at
high signal line on lobe. Do not remove.
2. Run an independent regulated air line to the valve actuator in place of positioner output
line. Slowly apply proper air pressure through the regulator to shut the valve. Do not
exceed designated supply pressure. (Handwheel may be used to close the valve in place
of regulated air line.) Align the travel indicator with the closed end of travel scale. Cam is
now at low signal line on lobe.
3. With cam at low signal line remove screw (28), lockwasher (51) and washer (27). Note the
relative position of the cam lobe being changed and then remove the cam (26).
4. Select the desired cam lobe and replace cam (26) on cam shaft with low signal line of
desired lobe against cam follower (4A). Ensure the newly selected cam lobe is in the same
relative position as the lobe noted in Step 3.
5. Replace washer (27), lockwasher (51) and screw (28). Reduce pressure applied in Step
2 to zero (back off the handwheel if handwheel was used). Disconnect the independent
regulated air line to actuator and connect positioner output line. Connect supply pressure
and signal to positioner. Check zero and span adjustment. Refer to “Zero Adjustment” and
“Span Adjustment” on page 37.