Katalog Produk

Keterangan

Mechanical loading on a component by a force leads to a mechanical tension, Formula: Ã = F–A , and to a strain, Formula: µ = �—l lo. As strain is a relative change in length of the loaded component, it is dimensionless. In most applications, strain measurement is used as a means of measuring the force on a component indirectly. The advantage of this is that the component undergoes practically no change as a result of the installation of the sensor, which is very small in size compared with the sensors used for direct measurement. In contrast to direct measurement of force, the strain measuring signal is dependent on the
force application point.

The strain is measured either at the surface or directly inside the structure.

The piezoelectric surface strain sensor is secured to a suitable point on the surface of the component with a single screw.

The mounting screw transmits the force between the two contact surfaces of the sensor and the component by stiction. A change in the longitudinal measurement of the component is transferred to the elastic element of the sensor, where it acts as a shear force on a piezoelectric sensor element. In complex structures, the right mounting point for the surface sensor must be determined by trial and error.

Strain sensors installed inside the structure require a cylindrical bore for mounting purposes. The advantage of this is that the measuring element can be placed where conditions are optimal. Since strains occur in different directions, Kistler offers sensors which measure strains which act lengthwise or crosswise in relation to the mounting bore. To enable these sensors to measure both tensile and compression strains, they are mechanically preloaded in the mounting bore.

Compared with conventional strain measurement technology, piezoelectric strain sensors are extremely sensitive.