Flowserve WRG Series Standard Actuator - Manual (Page 6)

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User Instructions WRG Series Standard Actuator - WCENIM0123-00 12/12
3 Heavy Duty Gear Overrides
Gear overrides on Worchester Controls WRG series heavy duty
actuators are available for models WRG1 through WRG5 provid-
ing a convenient and safe method for manually operating the
actuator, in event of supply failure. These are declutchable for
efficient, automatic operation. The gear override consists of a
declutchable gearbox mounted below the actuator, and is posi-
tioned between the WRG series actuator and the valve/damper
to be actuated.
Any accessories, such as limit switches and positioners, are not
disturbed and continue to be mounted on the NAMUR mounting
drive, on top side of the actuator.
The gear override is designed for the full rated torque of the
actuator and has an identical ISO base and bolting patterned, as
the actuator.
NOTE: In the event that needs the actuator to be removed
from the valve for maintenance or repair, the gearbox
can be left mounted on the valve, to allow manual op-
eration.
3.1 Installation
Worchester Controls standard sandwich gear overrides are pro-
vided as a modular component of the heavy duty actuator. Gear
override units are shipped with the gear mounted to the actua-
tor. The vent valves are installed on the pressure cylinder. No
additional customer installation is required. Refer Worchester
Controls Heavy Duty WRG series IOM (FCD WCENIM0121) for
instructions on installing Heavy Duty actuator into service.
3.2 Retrofit gear override onto existing WRG actua-
tor installation
3.2.1 Disconnect air pressure and electrical power from ac-
tuator and dismount the actuator from valve/mounting
bracket.
3.2.2 Thread in fully, the studs from the Gear Override Mount-
ing Kit, into the mounting base of the removed actuator.
3.2.3 Orient the manual override gear to the fail safe position
of the actuator, if actuator is spring return model, or else
bring both the actuator and the gear to the same posi-
tion, say Clockwise end. Back off the gearbox’s travel
stops.
3.2.4 The coupler shaft is fitted into and supplied with the
gearbox. The coupler shaft bottoms out on the step/
circlip inside the gear bore, preventing it from sliding
through the gear bore.
3.2.5 Mount the actuator on to the coupler shaft, into the yoke
bore of the actuator, aligning the keys on the shaft to the
keyways in the Yoke bore. Declutch the manual gearbox
(see instructions on gear box to disengage lock pin and
disengage the worm shaft).
3.2.6 Seat the actuator fully on the override gearbox flange and
thread in the Nuts with Lock washers from the Mounting
Kit, from below the mounting flange. Torque the Nuts to
rated torque for the Nut size.
3.2.7 Now this assembly is mounted on the valve stem or on
the bracket and coupler shaft, the way the actuator was
seated.
3.2.8 Bolt up the Gear drive mounting with the fasteners re-
moved from the actuator-valve mounting.
3.2.9 Fit the 3 way valves to pressure module, per schematic
(see Figs. on page 5).
NOTE: After mounting actuator to valve, the gear over-
ride travel stops must be set. First make sure that the
actuator travel stops are set correctly. Then set the
gear override travel stops to the same position.
3.3 Mount a preassembled actuator- gear override
assembly on the valve, a mounting bracket and
a Coupler/ Adaptor shaft is required with the
mounting kit.
3.3.1 Fix the mounting bracket on to the valve with the fasten-
ers from the mounting kit.
3.3.2 Locate the Coupler/Adaptor shaft supplied, on the valve
stem and lock to the stem.
3.3.3 Orient the actuator and the valve to same position, usu-
ally the fail safe condition of the actuator for SR/SO mod-
els and full clockwise end, for DA models.
3.3.4 Disengage the worm shaft from the worm wheel of the
override gearbox (see declutching instructions on the
override gearbox).Back off the override gearbox’s travel
stops.
3.3.5 Now mount the actuator-override gearbox assembly on
the coupler shaft, aligning the keys into the keyways in
the gear bore. Seat the actuator assembly on the bracket
and fasten with the mounting bolts.
3.3.6 Set the Actuator’s travel stops to the position required by
the valve.
3.3.7 Set the override gearbox’s travel stops to the same posi-
tion as the actuator, and lock the setting.