Woodward UG-Actuator Type A8251-766

Woodward UGActuator Type A8251-766

Rolls-Royce Marine part no. : 702447

• Proportional
  electrohydraulic
  actuator simplifies
  transfer from
  mechanical
  governing
• Economical
  installation using
  UG-8 case and
  drive
• Works with all
  Woodward
  20–160 mA output
  electronic control
  systems

The UG-A CTUATOR offers the advantages
of electronic control and load sharing
systems while using the convenient,
existing UG-8 type drives and linkages.
The actuator provides the muscle for
Woodward analog controls such as the
2301, as well as Woodward digital
controls such as the 500-series and 700-
series. The UG-ACTUATOR can be used
with diesel, gasoline, or natural gas
engines, and with steam and industrial
gas turbines. The UG-A CTUATOR has a
self-contained oil sump, so a separate oil
supply is not required.

The actuator operates with a low speed
pump for drive speeds from 375 to 1100
rpm, and with a high speed pump for 600
to 1500 rpm. An optional cooler is
available for applications with a higher
drive speed or high ambient temperature.
The UG-A CTUATOR is ideal for installations
involving unattended starts.
The optional self-contained MPU
simplifies the conversion of a UG-8
controlled engine or turbine to an
electronically controlled engine. A gear
which has been specifically designed to
operate the MPU means that the
electronic control will receive sharp, clean
speed signals. Low speed applications
may require override of the control’s
fail-safe during start-up.

The UG-A CTUATOR uses the same cast-
iron case as the UG-8 governor. The oil
pump is the proven high-output Gerotor,
designed to provide long life with minimal
maintenance. The actuator uses standard
UG-8 output shafts, power levers, power
pistons, and piston links. The base is
designed to precisely fit any drive
designed for a UG-8 governor, and
maintenance procedures are similar to
those of the UG-8 governor.
The actuator’s electric-to-hydraulic
transducer uses a Woodward-built torque
motor which converts the 20–160 mA
control signal to a given output position.