Preventive Maintenance

(Re)Packing columns

(Re)Packing columns

In packing columns (particularly 1/4•inchglass columns), one must consider the type of packing, column bore, and type (metal or glass), the method of sample introduction (flash vaporization or on•column),inlet or detector base requirements.

The method of sample introduction and/or the inlet/detector configuration determines the distance from the column end at which packing should start. Only general guidelines can be given here.

1.For FIDs and NPDs, at the detector end of the column, make sure neither packing nor a glass wool plug retaining the packing comes in contact with the bottom of the detector jet.

2.For 1/8•inchcolumns, where flash volatilization is used, packing should be as close to the inlet end of the column as feasible, leaving room for a glass wool plug to retain packing material.

Figure 8-1

Inlet End Flash

Detector

Vaporization

End

45 mm (1 3/4 in)

75 mm (3 in)

Glass Wool

Packing Limits for 1/4-inch Glass Columns

3.For 1/4•inchglass columns, since the inlet end serves as a liner, room must be provided to ensure flash volatilization and to ensure the syringe needle does not directly contact the glass wool plug and/or packing material. See Figure 8•1for recommended packing limits.

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