Hydraulic presses provide precise control of speed, force

Greenerd Press & Machine Co. Inc. has built and delivered three model HPBS-40 bench-type, C-frame, 40-ton hydraulic straightening presses for a U.S. airplane manufacturer. The presses, designed for straightening wing spar cords, feature electronic joystick ram control, made possible via proportional valve technology, which provides precise control of speed and force at any point of the machine's stroke.

The presses feature a compact control panel for digital control over press functions. A touchscreen helps simplify entry of setup parameters. Tonnage and ram position can be viewed at any position during each stroke.

The presses have a 20-in. daylight and a 14-in. stroke. Functions include pressure reversal, distance reversal, top stop, slow down, bottom stop stroke positions, manual speed control, and fixed pendant mounting at the head.

Release of either the joystick or palm button instantly stops the press ram. The user's free hand must actuate and hold the palm button for the joystick to be operated.