Sampling of gases
The sampling of gases occurs via gas extraction stations with nitrogen purging which are controlled by a multi-port ball valve. The sample cylinder (150 ml) is then filled with nitrogen in order to obtain a representative sample. Subsequently the cylinder can be filled with the gas sample. In doing so it must be ensured that there is adequate through flow as non-representative initial flow must be discharged. The through flow can be set with the help of a regulating valve and a flow meter in the range from 0.4 to 6.0 l/min.
After the gas cylinder has been filled with a representative sample in this way, switching to the bypass cylinder occurs via two multi-port ball valves and the sample is thus separated at the same time. In order to purge the pipe system it is possible to discharge the residual gas phase via the nitrogen pathway (purging system).
After this the sample cylinder must be separated from the station without danger and taken from the cabinet.
The sampling system is provided with a safety valve. Sufficient differential pressure for through flow must be guaranteed. The system to the outflow can be shut off via a ball valve.