Flowserve WRG Series Standard Actuator - Manual (Page 4)

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User Instructions WRG Series Standard Actuator - WCENIM0123-00 12/12
2 Heavy Duty Jackscrew Overrides
Jackscrew overrides on Worchester Controls heavy duty ac-
tuators provide economical, durable method for manually
operating the actuator. The jackscrews are either direct oper-
ating or bevel gearbox driven, to reduce operation effort. The
direct operation consists of a rotating screw, threading into
the nut which is fitted on the Torque module/ Spring module,
and the hand wheel directly turns the screw.
The bevel gearbox driven jackscrew, has an arrangement of
rotating nut and a rising screw. The higher thrust require-
ments for models bigger than 4000 Nm and for the stiffer
springs are met with this type of jackscrew design.
Jackscrews are available on models WRG1 through WRG5.
2.1 Installation
worchester Controls standard jackscrew overrides are pro-
vided as a complete integral component of the heavy duty
actuator. Override units are shipped with the jackscrew as-
sembly mounted to the actuator and vent valves installed on
the pressure module. No additional customer installation is
required. Refer Worchester Controls Heavy Duty IOM (FCD
AXENIM0121) for instructions on installing Heavy Duty ac-
tuator into service.
2.2 Install jackscrew override onto heavy duty DA
actuator (see Fig.: 1)
2.2.1 Disconnect air pressure and electrical power from ac-
tuator.
2.2.2 Remove the DA end cover plate.
2.2.3 Back off the jackscrew fully in the assembly and
mount the jackscrew assembly on the torque module
end flange, locating the spigot in the Torque module.
2.2.4 Use the jackscrew mounting kit and the O-ring from
the DA cover.
2.2.5 Tighten the mounting stud nuts fully, with lock wash-
ers from the kit.
2.2.6 Fix the 3 way vent valves supplied in the kit, to both
ports of the pressure module and connect air supply
pressure lines to these valves.
2.2.7 Installation of pressure module side jackscrew re-
quires replacement of std end plate of the pressure
module. Remove tie rod nuts and end plate, and fit in
the jackscrew assembly, supplied preassembled with
the suitable thrust base End Plate. Tighten the tie rod
nuts back on the pressure module. Fix the 3way valve
on the ports.
2.3 Install jackscrew override onto existing heavy
duty SR actuator (see Fig.: 2)
2.3.1 Disconnect air pressure and electrical power from ac-
tuator.
2.3.2 Remove the end cover plate on the Spring module, re-
taining the cover O-ring.
2.3.3 Tighten the mounting studs from the mounting kit with
thread lock compound into the spring module end
plate.
2.3.4 Back off the jackscrew fully in the assembly and mount
the jackscrew assembly on the spring module end
plate’s thrust base, locating the spigot in the spring
Fig.: 1 Install Jackscrew Override (DA)