What are the pressure forces generated by the calibration device that are introduced as equal magnitude tensile forces into the calibration object?

The English translation of "Welche die durch die Kalibriereinrichtung erzeugten Druckkräfte als betragsgleiche Zugkräfte in den Kalibriergegenstand einleitet." is: "Which introduces the pressure forces generated by the calibration device as equal magnitude tensile forces into the calibration object."