Baker Hughes Masoneilan 4700P, Инструкция по эксплуатации

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Masoneilan 4700P/E & 4800P/E Positioners Manual | 41 © 2021 Baker Hughes Company. All rights reserved.
forward and will rest on the cam follower. See appropriate table for cam selection. Secure
cam (26) to cam holder (36) with washer (27), lockwasher (51) and screw (28). Tighten
screw (28) while holding the cam (26).
6. With the valve open, place the desired cam lobe’s low signal line on the cam follower (4A).
With the low signal line resting on the cam follower sight across the face of the cam to the
raised reference line on the positioner case and align. (Low signal line and reference line.)
Center cam between the two arms of the lever S/A (3) then tighten set screws (35) to 87
inch-lbs. torque. (See Figure 18 on page 56 for cam mounting.)
7. Slowly reduce pressure applied to actuator in Step 3 to zero. (If handwheel was used to
place valve in open position, back it off completely.) Cam is at high signal line on lobe.
8. Disconnect the independent regulated air line to actuator and connect positioner output
line. Connect supply pressure and signal to positioner.
9. Adjust signal to low end of signal (i.e., 3 psig for a 3-15 psig range 4700P/4800P). Adjust
zero and span. Refer to “Zero Adjustment” and “Span Adjustment” on page 37.
Air to Close / Direct Acting Positioner
See Figure 18 (page 56) and Figure 19 (page 58).
1. Do not connect air supply or signal to the positioner. Valve is now open.
2. Note the valve position. The travel indicator should be approximately aligned with the open
end of the travel scale. If not aligned, consult proper valve instruction for travel adjustment.
3. With valve open, place lever S/A (3) to proper side (left or right) as designated by the
appropriate cam selection table for valve in question.
4. With valve open, place cam holder (36) with truarc ring (37) into cam coupling (34).
5. Place the cam (26) onto the cam holder (36) so that the selected cam lobe is facing
forward and will rest on the cam follower. Secure cam to cam holder with washer (27),
lockwasher (51) and screw (28). Tighten screw (28) while holding the cam (26).
6. With the valve open, place the desired cam lobe’s low signal line on the cam follower.
With the low signal line resting on the cam follower sight across the face of the cam to the
raised reference line on the positioner case and align. (Low signal and reference line.)
Center cam between the two arms of the lever S/A (3), then tighten set screws (35) to 87
inch-lbs. torque. (See Figure 18 on page 56 for cam mounting.)
7. Connect air supply and signal to positioner. Connect positioner output to valve actuator.
Refer to connection diagram for valve in question. Adjust signal to low end of signal (i.e., 3
psig for a 3-15 psig range 4700P/4800P; 4 mA for 4-20 mA 4700E/4800E). Adjust zero and
span. Refer to “Zero Adjustment” and “Span Adjustment” on page 37.