Agilent Technologies G3180B - Manual (Page 48)

48 Installation and Operation Guide
4 Operation
The restrictor to the MSD was 0.824 m of 0.18-mm id tubing. The backflushing
temperature used here is the hold temperature at the end of the run in the
original method (280 °C). The flow calculator (
Figure 23 ) shows that the
makeup pressure can be programmed to 17.4 psig at 280 °C.
The time required for complete backflushing of heavy materials is then
determined empirically. Blank runs after samples with different backflush
hold times are used to determine the minimum time to remove all heavy
material.
Figure 23 Column backflush flow calculation