Columns and Fittings
Jet replacement, FIDs or NPDs
Jet replacement, FIDs or NPDs
Depending upon the column type (packed versus capillary) to be used, and/or analyses to be performed, exchanging the jet in an FID or NPD may be necessary. This must be done prior to column installation, and is particularly important in optimizing FID performance.
Exchanging the jet in either an FID or an NPD is described in Chapter 8, Preventive Maintenance.
Metal capillary columns
Most metal capillary columns (0.6 to 1.0 mm od) can be connected directly. Some metal capillaries have a large•diametersleeve soldered on each end; this must be removed. Use a small triangular file to score the tubing behind the sleeve; then bend the sleeve back and forth until it breaks.
It is important to have fresh ends of the column, free of burrs, jagged edges, and/or loose particles of column, stationary phase, and/or material from a sealing ferrule or O•ring.
Therefore, whenever the column must be cut to provide fresh ends, use a suitable file to first score the column at the point at which it is to be broken. This is done normally after installing on the column the column nut and ferrule (or O•ring)required for installation.
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