Specimen Holders and Adaptors
In order to achieve the lowest possible measuring error and to maximize reproducibility in material testing, the correct point transmission of force is essential. Minute deviation in regard to the force axis and lateral forces will lead to measuring errors exceeding the given measuring uncertainty of an universal testing machine by far.
Therefore the specimen holders and grips have a substantial influence for the total uncertainty of measuring values. Many standard refer directly or in their attachment to the design properties of adapters, grips and specimen holders.
The load cell as well as the fixed traverse (specimen stage) provides threaded holes or shaft ends with cross hole to adapt grips and holders. Rotation symmetrically constructed grips (e.g. intruders) can be adapted onto a thread. If two grips must be reference to a specific position or have to be aligned, an adaption with shaft and crossbar is recommended.