Woodward TG-10E, Installation And Operation Manual

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Manual 04045 TG-10E/-13E/-17E Actuator
Woodward 7
Make the required piping connections to the cooler and the actuator. See Figure
3-2 which illustrates piping connections. The cooler must be installed in the line
to the cover filter.
Figure 3-2. Heat Exchanger Piping Connections
Use a pipe size that minimizes pipe pressure losses to less than 15 psi (103
kPa). Oil flow from the oil to cooler inlet tap (.125-27 NPTF) is 1.0 gal/min (3.8
L/min) on an actuator operating at 6000 rpm and using a 0.250 thick Gerotor
pump (0.250 is standard thickness on high rpm actuators). For the TG-17E, it is
1.2 gal/min (4.5 L/min) at 200 psi (1379 kPa).
We recommend that a throttling device be installed to the heat exchanger so that
coolant flow is regulated for optimum oil temperature. Excessive cooling of
actuator oil can cause sluggish operation.
When is a Heat Exchanger Necessary?
Some applications of the TG may require an oil heat exchanger be used to
prevent oil breakdown and subsequent problems due to excessive oil operating
temperatures. TG actuators operating at low and medium speed ranges (1100–
2400 and 2400–4000 rpm) do not normally require a heat exchanger. The high
speed actuator (4000 to 6000 rpm) may require a heat exchanger in some
applications. Factors such as oil viscosity, actuator speed, heat radiation from
surrounding sources, and mounting pad and ambient temperatures affect oil
conditions, necessitating an oil cooler (see Woodward Manual 25071,
Oils for
Hydraulic Controls ). Generally, when oil viscosity at operating temperature is
below 100 SUS (Saybolt Universal Seconds), an oil cooler is required.
A single pass, counter-flow heat exchanger with 1 to 2 ft² (0.09 to 0.19 m²) of
heat transfer area, provides adequate cooling for most high speed TG actuators.
If there is doubt concerning the need for, or size of, a heat exchanger, contact
Woodward. Heat exchangers can be purchased from Woodward.
Oil Supply
Use this information as a guide in the selection of a suitable lubricating/hydraulic
oil (for more information on oils, refer to manual 25071).