Woodward TG-10E, Installation And Operation Manual

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TG-10E/-13E/-17E Actuator Manual 04045
20 Woodward
Calibration Procedure with Actuator on a Test Stand
If a TG actuator requiring a customer-supplied hydraulic pressure source is to be
recalibrated, in addition to using the procedure described below, be sure to meet
the following requirements:
•
Supply the filter fitting with the oil filtered to 10 to 30 µm (nominal). This
ensures that the 40 µm filter fitting is not contaminated.
•
The drain flow must be approximately 1 to 2 gal/min (4 to 8 L/min) to ensure
that the accumulator is bypassing. The oil supply pressure must be 160 psi
(1103 kPa) minimum.
Use the following procedure to calibrate the TG actuator:
1.
Mount the actuator vertically on the test stand.
2.
Remove the cover and plug the oil line to the actuator filter.
3.
Connect a test circuit to pins A and B on the pin connector to the actuator.
The test circuit is shown in Figure 4-2.
4.
With no current applied, make sure that there is no travel of the terminal
shaft from the minimum position.
5.
A recalibration is required if any one of the following conditions exists:
(1) With 20 mA current applied, if less than 1-degree movement or more
than 3-degree movement is seen from minimum position
(2) With 160 mA current applied, if less than 37-degree movement or more
than 39-degree movement is seen from minimum position (27 to 29
degrees for TG-10E)
(3) If the terminal shaft does not rotate smoothly from one position to
another, or if it does not take the same position for the same
potentiometer setting when rotated from the increase or decrease
position.
6.
If none of the conditions listed in Step 5 above exists, a recalibration is not
required. Drain actuator oil; fasten the cover with eight cover screws and
torque screws to 100 lb-in (11.3 N
x
m). Reinstall the filter supply tube.
7.
If condition (1) or (2) in Step 5 above exists, skip Step 8 and go to Step 9 to
recalibrate the actuator.
8.
If condition (3) in Step 5 above exists, the transducer assembly must be
disassembled before recalibrating the actuator to make sure that there is no
binding of the feedback lever, spring, transducer assembly, or pilot-valve
plunger.
Disassemble and reassemble the transducer assembly as explained
previously in Step 11 of the previous section.
9.
Install and secure a protractor over the terminal shaft. Use the terminal shaft
as an indicator and rotate the output shaft over its full range of travel. Mark
the minimum and maximum shaft positions on the protractor. The total
terminal shaft travel must be 40 degrees.
10. Use SAE 10 oil at 60 degrees F to 180 F. Fill actuator to within 2 inches of
top. Always use an oil filter with 140 µm maximum rating on the accumulator
bypass during recalibration.