Val-Matic 30 and Larger Butterfly Valve With LSA Actuator and External Stops - Manual (Page 7)

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CAUTION: Opening and Closing of the valve
should be done slowly to prevent
water hammer.
A traveling nut actuator (Figure 7) has a threaded rod
(16) that drives a threaded crosshead (14) from one
end of the housing to another. The crosshead in turn
drives a slotted lever (9) through 90 degrees of
rotation. Traveling nut actuators provide slower
rotation and greater torque multiplication at the ends of
travel. A bevel gear mounted on the input side of the
actuator provides additional torque.
Both worm gear and traveling-nut actuators are self-
locking and multiply the turning force on the handwheel
or nut so that valves can be operated with ease. A
clamp-on chainwheel kit can also be used for
installations high above the floor. An indicator on the
top of the actuator housing indicates the position of the
valve plug. The handwheel or nut must be rotated
through 35-290 turns (depending on model) to open or
close the butterfly valve. The direction of rotation to
open the valve is indicated on the 2" square actuator
nut and handwheel. The standard direction of rotation
is open left or counter-clockwise to open. Nuts with
opposite rotation (open right) will be painted red to
indicate their special rotation.
GEAR ACTUATOR ADJUSTMENT: The standard
gear actuator is provided with factory-set open and
closed position stops to properly center the closed disc
seal in the body seat. No field adjustment is
necessary. If adjustment is needed over time, the
external closed stop nut (19B) can be turned to change
the closed position of the valve.
VALVE SEAT ADJUSTMENT: If the valve is found to
leak in service, the rubber seat can be adjusted. With
the valve in the closed position, tighten the three seat
bolts in the area of the leak 1/4 turn at a time until the
leak stops.
The factory settings for the seat bolts are given in
Table 4 for reference in case the valve cannot be
tested while under pressure. These torques are for
use with the disc in the closed position. Torques
greater than 150% of these will make the valve difficult
to operate.
TABLE 4. SEAT BOLT TORQUES
MAINTENANCE
The Series 2000 Butterfly Valve requires no scheduled
lubrication or maintenance other than regular
exercising. The exercising is achieved by fully opening
and closing the valve to verify smooth operation. If
operation is difficult, it may be necessary to flush
sediment from the valve by opening and closing the
valve several times under flowing conditions or
checking the lubricant in the gear actuator.
The recommended interval for exercising is every six
months or annually if the valve is regularly operated.
Over the life of the valve, inspection and some regular
adjustments may be needed as given below.
PACKING ADJUSTMENT: The shaft is equipped with
a set of V-shaped packing, which is factory-set for
drop-tight service. The packing is pressure assisted
and does not normally require adjustment. Should
leakage occur, the packing can be replaced.
PACKING REPLACEMENT: To replace the packing, it
is recommended that the line be drained and the
actuator removed. The valve can remain in the line.
1. To replace the packing, first open the valve and
drain the line.
2. Close the valve to hold the plug in position. For
power actuators, turn off and lock out electrical and
hydraulic supplies before proceeding.
3. Remove small round cover on actuator to expose
shaft and key.
4. Remove actuator mounting bolts and adapter plate
or packing retainer plate.
5. Lift actuator and plates from valve taking care not to
lose square key.
6. Remove old packing (13) with packing hook.
7. Lubricate new packing with FDA grease and set in
place one ring at a time taking care not to bend
over the lips of the packing rings.
WARNING: Drain Line and close valve
before removing actuator or
valve may rotate suddenly
causing bodily injury or damage
to property.
SIZES CLASS 150B CLASS 250B
30”-48” 20-25 25-30 ft-lbs
54”-108” 25-30 30-35 ft-lbs