This extensometer has been designed as a highly accurate, stable measuring device for high temperature tensile tests in a split furnace. The measuring accuracy meets the requirements of the ISO 9513 class 0.5. 2 initial gauge lengths are offered as standard. GL 25 mm and GL 50 mm can be adjusted quickl. Due to its extremely low operation force, the unit enables the testing of highly sensitive samples which permit only the lowest surface pressures.

This extensometer offers 2 initial gauge lengths (25 and 50 mm). Depending on the desired initial gauge length, the arms either have to be inserted into the extensometer housing through the inner bores (GL 25 mm) or the outer bores (GL 50 mm) of the heat protecting shield. Therefore the clamping screws have to be unlocked approximately one turn, using the 2.5mm screwdriver (standard accessory). The arms have to be inserted into the extensometer housing to their mechanical stop, at the same time, care has to be taken, that the shapes of the arms are in a horizontal position. Finally, the clamping screws have to be fixed tightly.

After the correct mounting of the arms the initial gauge length can be adjusted accurately. Therefore the extensometer has to be in the measuring position and the tuning screw “8” has to be unlocked. The upper arm can now be adjusted. Put now the gauge length pattern with the 90° groove on the feeler arms and tighten the screw “8”. The setting has to be checked again. With the correct setting, the GL should now be 25 mm respectively 50 mm (+/- 0.1 mm).