MTS Systems SilentFlo 505G2 Series, Руководство пользователя

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Operation
52 Series 505G2 SilentFlo™ Hydraulic Power Unit
The following procedure assumes that Steps 1 through 3 of “Adjusting the HPU output pressure level”
have already been completed.
1. With the HPU running in high, loosen the nut on the Auto-Cooling Valve located on the control
manifold (see the previous figure).
2. Adjust the Auto-Cooling Valve to shift at the desired level.
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When increasing the output pressure, adjust the Auto-Cooling Valve clockwise to the
desired shift level.
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When decreasing the output pressure, adjust the Auto-Cooling Valve
counterclockwise to the desired shift level.
Note: The number of turns required to reach the transition level will depend on the how
much the output pressure is changed. For example, going from an output pressure of
21 MPa (3000 psi) to 14 MPa (2000 psi) may require as much as three full turns on the
Auto-Cooling Valve before you approach the transition level.
While adjusting the Auto-Cooling Valve, listen to the pump. 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.
An alternative to listening for a change in pump pitch is to hold the return line hose at the
manifold while making the valve adjustment to feel when the resultant flow stops or starts.
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. 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.
4. If necessary, repeat Steps 2 and 3 until the Auto-Cooling Valve is stable and the HPU cools
properly.
5. After the final adjustment tighten the nut to secure the setting.