Solar Collector Tube Industry
In the field of solar thermal energy, vacuum tube collectors are very frequently used. High internal pressure is required for high efficiency and service life of the tube. In order to avoid damage to the heat exchangers, the residual moisture has to be removed as completely as possible from the tubes. Due to the high quality requirements and long guarantee periods, sampling tests are increasingly replaced by 100% tests.
GNT systems test the existence of the required vacuum and enable the detection of foreign gases, e.g. the harmful hydrogen, which can be identified by a clear red color.
The examination of solar thermal components is usually carried out visually or by an evaluation by means of image processing, due to the extremely low luminous intensity.
The picture shows the test of a solar thermal vacuum tube which contains residual hydrogen. The easily visible reddish coloration is an indication of the presence of hydrogen.