These illustrations show basic sample injection techniques using Cheminert two position valves. With rare exceptions, there is no difference between switching valves and external volume sampling valves, so the same valve can be used for either function.
The unique advantage of 8 and 10 port valves is that they reduce extra column volume by combining sampling and switching functins in a single valve. This minimizes expense, maintenance, service, and risk of leaks as compared to multiple 6 port valve systems.
Applications, listed alphabetically
|Alternate column regeneration||10 port|
|Detector selection from two columns, or one column and auxiliary carrier||4 port|
|Loop sampling with backflush to detector||8 port|
|Microvolume sample injection||4 port|
|Sample injection||6 port|