MTS Systems SilentFlo 505G2 Series, Руководство пользователя

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Operation
Series 505G2 SilentFlo™ Hydraulic Power Unit 53
6. Hold the HPU Output Pressure Control to prevent it from turning while tightening the nut.
7. Verify that the output pressure remained at the desired level and tighten the nut to secure the
setting.
A. Hold the Auto-Cooling Valve stem to prevent it from turning while tightening the nut.
Adjusting the Auto-Cooling Valve if the HPU shuts down due to an over-temperature
condition or if the HPU fails to deliver the full flow to the external circuit.
Adjust the Auto-Cooling Valve if:
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The HPU shuts down due to an overtemperature condition that has been determined to not be
caused by a fault in the heat exchanger circuit or
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If the HPU fails to deliver the full flow of the HPU to the external circuit.
1. With the HPU running in high and the HPU set for the desired output pressure, loosen the nut
on the Auto-Cooling Valve located on the control manifold.
2. Adjust the Auto-Cooling Valve setting by slowly turning the valve clockwise. If the valve shifts,
a sudden change in pitch will be heard from the pump. Reversing the valve adjustment a
number of times will aid in identifying the proper setting. Make a final counter-clockwise
adjustment. An increase in pump pitch will be heard that corresponds with the opening of the
valve. Stop adjusting at this point. If no valve shift is audibly or visually detected and the valve
has been fully closed go to step 3.
Important:
Adjustment of the Auto-Cooling Valve to a level too close to the desired output pressure
may cause an unstable condition characterized by rapid valve shifting. This condition
will produce an audible flutter and can be seen as an erratic movement of the needle on
the pressure gage.
Adjustment of the Auto-Cooling Valve at or above the desired output pressure may
prevent the valve from shifting and result in the HPU overheating.
Adjustment of the Auto-Cooling Valve that results in the valve shifting at a level
substantially below the desired output pressure may result in reduced flow to the
system.
3. Adjust the Auto-Cooling Valve by slowly turning the valve counter clockwise. When the valve
shifts a sudden change in pitch will be heard from the pump. Reversing the valve adjustment a
number of times will aid in identifying the proper setting. Make a final counter-clockwise
adjustment, an increase in pump pitch will be heard that corresponds with the opening of the
valve. Stop adjusting at this point.
4. Confirm the Auto-Cooling Valve setting by slowly cycling the HPU Output Pressure Control.
Decrease the HPU output pressure and note a decrease in pump pitch when the valve closes.
At the point when the valve closes the pressure on the gage will momentarily hesitate during
the adjustment. Increase the pump output pressure to the desired pressure setting and note
an increase in pump pitch when the valve opens. Once again the pressure gage will show a
momentary hesitation when the valve opens.