Screws and Fasteners
The test is performed in compression and applied a shear load perpendicluar to the axis of the fastener. The convenient compression space of the Quasar machine allow to easily center the double shear fixture and fastener. A precise load application is important to avoid creating different forces that could alter test results. The fast data sampling rate of the Galdabini electronics provided accurate control during loading.
In order to achieve a steady test rate during yielding, Our software is configured to automatically change from stress to position control at the same relative rate just prior to yielding. This prevented acceleration from occurring at the onset of yielding. The break detection criterion is set at a very sensitive level and allow shear to occur without total failure of the fastener. Labtest software automatically generated the required shear strength and peak load values at the end of the test.