Answer
The Framo pump performance is assessed by checking the relationship between hydraulic system pressure, cargo discharge pressure, and pump RPM.
Performance Test: Run the pump against a closed or throttled discharge valve while monitoring the hydraulic pressure drop across the pump motor and comparing it with the shop test curve.
Min & Max Spool Angle: Framo hydraulic power packs utilize axial piston pumps where the displacement is controlled by changing the swashplate or spool angle.
Minimum Spool Angle ($0^\circ$ to $5^\circ$): Occurs during "Standby" or zero-load conditions. The pump maintains minimum system pressure (approx. 15-20 bar) just to keep the system lubricated and responsive without delivering volume.
Maximum Spool Angle ($18^\circ$ to $21^\circ$): Occurs under full discharge load demand. The pump shifts to maximum geometric displacement to deliver the rated hydraulic oil flow rate at maximum working pressure (typically 250-280 bar).