Fisher-Rosemount 3024S, Инструкция по эксплуатации

Страница: 5 / 20

Design 3024S
5
b. Tighten the valve bonnet lock nut.
c. Adjust the travel: rotate the connector halves (key 53
and 50) so that the distance between them (with the plug
on the seat and the travel indicator key 51 between the
connectors) is equal to the valve travel.
d. Exhaust the actuator slowly and adjust the stem con-
nector half (key 50) so the connecting bolts will line up.
e. Completely exhaust the actuator and tighten all bolts
(key 55/56) and nuts (key 56/57).
f. Apply approximately 0.5 bar above the heighestbench
set pressure to the top of the diaphragm and check the
valve stem travel.
g. Tighten the valve stem hex nut (key 54/52) against the
stem connector (key 50).
For a Type 3024S Air-To-Open & Air-To-Close
actuators:
5. Cycle the actuator several times to check for proper
operation.
6. Adjust the travel indicator scale (key 26) up or down to
correspond with the travel indicator.
Travel Adjustments
Although making travel adjustments should not be neces-
sary if previous section on Actuator Mounting has been
followed, use the following procedure when the actuator
travel is different from that stamped on the actuator name-
plate (figure 2).
When adjusting the travel of a push-down-to-close valve air-
to-open actuator combination, slightly pressurise the ac-
tuator. This moves the valve plug off the seat, reducing the
chance of damaging the valve plug or seat during adjust-
ment.
1. Back off the stem hex nut (key 54/52) from the valve
stem connector, and slightly loosen both/all 4 cap
screws (key 55/56) from the connectors.
2. Screw the connector (key 50) clockwise (to lengthen
travel) or counter-clockwise (to shorten travel).
3. Tighten the stem connector cap screw (key 55/56).
4. Cycle the actuator to check for the specified travel. If the
travel is not equal to the specified travel, adjust and
check it until it is correct. Tighten the stem hex nut (key
54/52) against the stem connector.
Maintenance
Actuator parts are subject to normal wear and must be
inspected and replaced as necessary. The frequency of
inspection and replacement depends upon the severity of
the service conditions. Due to the care Fisher takes in
meeting all manufacturing requirements (heat treating,
dimensional tolerances, etc.), use only replacement parts
manufactured or furnished by Fisher.
This section describes how the actuator can be completely
disassembled and assembled. When inspection or repairs
are required, disassemble only those parts necessary to
accomplish the job; then start the assembly at the appro-
priate step.
Key numbers refer to figure 6 for a Size 1.21/1.31 Air-To-
Close actuator, to figure 7 for a 1.21/1.31 Air-To-Open
actuator, figure 9 for a Size 1.41 Air-To-Close actuator, to
figure 10 for a 1.41 Air-To-Open actuator.
Disassembly
Avoid personal injury or damage to prop-
erty from sudden release of pressure, un-
controlled process fluid, or precompressed
spring force. Before starting disassembly:
· Isolate the valve from the process,
· Release process pressure,
· Vent all internal pressure from the actua-
tor,
· Release all spring preloading force,
· Use lock-out procedures to be sure that
the above measures stay in effect while
you work on the equipment.
1. For complete disassembly, the positioner and all ac-
cessories (if attached) must be removed from the
actuator. Follow the appropriate removal procedures in
the instruction manuals supplied with the positioner and
accessories.
2. Bypass the control valve. Reduce the loading pres-
sure to atmospheric, and for a bottom-loaded Type
3024S Air-To-Open actuator, remove the tubing or
piping from the connection in the lower diaphragm
casing (key 1).
For a top-loaded Type 3024S Air-To-Close actuator,
remove the piping or tubing from the connection in the
upper diaphragm casing (key 16).
3. Slightly loosen all diaphragm casing cap screws (key 19
and 21). Remove the plastic hose (key 22). Unscrew the
short and long diaphragm casing cap screws and nuts
(key 19,20 and 21) alternately, until only the long casing
cap screws (key 21) remain engaged. Then allow the
remaining spring compression to be slowly and evenly
released by alternately unscrewing the long casing cap
screws.
!
W A R N I N G W A R N I N G
W A R N I N G W A R N I N G W A R N I N G