| 摘要 |
A device for controlled withdrawal of samples of fluid substances, in particular of liquids from a process, comprises a pump (10) which is connected on the inlet side with a suction line (11) for intake of the fluid substance and on the outlet side with a pressure line (12) connected through a three-way valve (13) to a sampling tube (15). The other end of the sampling tube (15) is connected through a second three-way valve (14) to a discharge line (16), so that the test substance can be withdrawn continuously throughout the process, conveyed through the sampling tube (15) and returned to the process. The third inlet of the first valve (13) is connected to a compressed gas source (18), and the third inlet of the second valve (14) is connected to a withdrawal line (19). If the valves (13, 14) are reversed so that the pump (10) can no longer deliver the substance to be sampled through the sampling tube (15), the volume in the sampling tube (15) is acted on directly by compressed gas and conveyed to an analytical device (23). |
