PI Piezo stack actuators are extremely reliable and have exceeded life time tests of 100 billion cycles. Nevertheless, they should be handled with care because the internal ceramic materials are sensitive to shock, bending and torsion forces. Preloaded Stack Actuators can handle tensile forces.
Flexure Guided Actuators provide the best protection along with increased travel ranges and guiding accuarcy. Mounting and Operating Instructions for Piezo Positioning Stages
1. Piezo stack actuators must only be stressed axially. Tilting and shearing forces must be avoided (by use of ball tips, flexible tips, etc.) because they will damage the actuators.
2. Piezo stack actuators without internal preload are sensitive to pulling forces. An external preload is recommended for applications requiring strong pulling forces (dynamic operation, heavy loads, etc.).
3. Maximum allowable torque the top piece (for encased and preloaded actuators) can be found in the respective data sheets. Proper use of wrench flats to apply a counter torque to the top piece when a mating piece is installed will protect the ceramics from damage.
4. When piezo ceramic actuators are installed between plates, a ball tip is recommended to avoid bending and shear forces.