Deformations

Accelerations, velocitys, Deformations, Strains and Temperatures can be measured by using different measuring sensors. The planning and construction of the respective measurement chain can be carried out by SKI together with cooperation partners.

For example, during a welding test at the Institute of steel construction of the der Leibniz University Hanover , two square plates were monitored by measurement during the welding process. With the aid of a tractor arm, the welding nozzle moved at a defined feed rate. In this respect, a fully mechanical welding process was used to achieve a very uniform weld seam quality and weld seam shape over the entire length of the seam.

While for the right plate inductive displacmenet transducer and Strain gages were used, the left plate was coated with a high temperature resistant and stochastic pattern with an airbrush gun. The black-and-white contrast was required for the optical measuring system used to perform the 3D-deformations analysis . In addition, the welding nozzle had to be coated in order to protect the sample from welding spatter and traces of smoke.

The following figure shows the shrinkage path in the longitudinal direction of the seam as a function of time. The results from the welding simulation (HANWELD) were compared with the path measurements from the optical sensor and LVDT. A good agreement can be seen from the curves.

In addition, thermocouples were arranged at points to enable comparison with the temperature field of a welding simulation after the welding test.

Services

SKI Ingenieurges. mbH offers the following services in the field of deformation measurements:

Test accompanying and monitoring activities
Construction and calibration of numerical models for recalculation
Recalculation of test results in the static, dynamic and transient range
Evaluation and interpretation of measurement results, as well as comparison of numerically supported test methods
Creation of measurement concepts, reports and expert opinions