Flowserve XL Series High-Performance Positioner - Manual (Page 4)

45-4 Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611
positioner. Figures 11 through 16 show the shaft
rotation versus instrument signal of a valve (Valdisk,
ShearStream or MaxFlo). These graphs should be
used when visually checking the valve shaft rotation
versus positioner signal relationship.
Reversing Air-Action of XL Series
Positioners on Rotary Actuators
Reversing the action on rotary actuators is achieved by
mounting the yoke to the opposite side of the transfer
case. Refer to maintenance instructions ‘Spring Cylinder
Rotary Actuators’ for details.
Note: When reversing action on rotary actuators, also
change cam. (See Table I.)
positioner with part identification number facing out to
the right side. Slide the cam shaft through the inner
bearing and then slip flatted hole of the follower arm
over the longer stepped shoulder of the cam shaft.
3. Place a small amount of thread-locking compound
(Loctite No. 222 or equivalent) to the threaded portion
of cam shaft nut. Slide the cam shaft nut through outer
bearing and screw it onto the cam shaft. Tighten the
cam shaft together firmly so that the follower arm is
securely clamped. Also, make sure the cam is tightly
secured to cam shaft. Check to be sure there is no
slippage. Apply a small amount of grease to the bent
end of the return spring and feed it through the hole in
the cam. Loop the other end of the return spring over
the screw and screw it into the positioner base.
NOTE: Screw head will not bottom out.
4. Rotate the zero adjustment arm back into place and
reinstall the feedback spring.
5. If the follower pin is present, insert it into the hole in the
actuator lever arm and drive it firmly into place with a
hammer. (See Figure 5.)
6. Apply grease to the sliding surfaces of the follower
arm before mounting the positioner to the transfer
case. When mounting the positioner to the transfer
case, make sure to guide the follower arm so the pin
slides in the slot on the follower arm. (See Figure 5.)
Fasten the positioner to the transfer case with the
three mounting screws. Push up on the cam to verify
the pin is riding in the follower arm slot or remove
transfer case cover plate to inspect.
CAUTION: Failure to replace the cover plate be-
fore pressurizing or operating the actuator will
cause damage to the shaft since the cover plate
houses a shaft-support bearing.
Depending on the positioner cam side selected, the
valve flow characteristic may be linear or equal per-
cent when compared to the instrument signal to the
Figure 5: XL Series Positioner
Installation on Valtek Rotary Actuator
Figure 6: Cam Return Spring Installation
POSITIONER CALIBRATION
Introduction
Valtek positioners are calibrated at the factory; how-
ever, due to shipping and handling, it may be necessary
to check the calibration before operating the valve. The
XL positioner, for strokes
3 /
4
-inch and above, can be
calibrated to a range of 3-15; two-way split range, 3-9,
or 9-15; and three-way split ranging, 3-7, 7-11, 11-15
psi using the standard feedback spring. An alternate
red colored feedback spring on linear actuators is used
for strokes less than
3 /
4
-inch.
WARNING: When stroking the actuator during cali-
bration, keep hands, hair and clothing away from
moving parts. Failure to do so may cause serious
personal injury.
Note: Positioners and I/Ps are calibrated at the
factory. Use mechanical adjustments in positioner
for calibration. Zero and span on the I/P should not
be used to calibrate valve.
For calibration, proceed as follows:
1. For 3-15 or 3-9 psi range, loosen by hand the zero
adjustment locking knob and adjust the zero adjust-
ment knob until the valve begins to stroke with more
than 3 psi signal (for 9-15 psi range adjust to 9 psi).
2. Loosen the range adjustment locking screw no
more than 1 /
8
turn.
Read Cam
Characteristics
from this side only
Follower
Pin
Follower
Arm
Cam
Actuator Lever Arm
Return Spring
Cam
Grease Here
Cam Shaft
Screw
Lock
Washer
Nut
Read Cam
Characteristics
from this side only