Replacement of Septum

Preparation

First, set the instrument to a state in which it can be serviced (Maintenance Mode).

Required devices

No.
Parts name
Category
Required number
Note
①
Tweezers
Other
1
②
Septum
Inlet Septum
1
Various optional parts are available.
③
Spacer
Parts for Injection Unit
1
Parts for SINJ.

Procedures

Step 1

Open INJ/DET cover (★1).

For GC-2050, do maintenance work without opening the INJ/DET cover. Turn off the power before opening the INJ/DET cover.

Step 2

Turn the septum nut (★2) counterclockwise to remove it.

Note

The appearance depends on the injection port. For SINJ, it is as follows.

Step 3

Remove old septum (★3) with tweezers (①).

Note

For a SINJ, there is a spacer (③) under the septum. When replacing it, make sure that the surface with the slit faces downward.

Step 4

Install a new septum (②).

Hint

Hold down the septum with flat surface of tweezers for easier installation.

Step 5

Turn the septum nut (★2) clockwise, fully tighten it, and return it halfway.

Hint

  • If it is not returned halfway, the septum may become hard and the needle of the syringe may bend when the syringe is inserted.

  • Returning halfway after fixing prevents the septum from excessive compression, which makes it difficult to insert the syringe.

Step 6

Close INJ/DET cover.

Step 7

Exit maintenance mode using the following procedure according to the relevant instrument, and reset the consumable usage counter.

Hint

Type of bleeding depends on the septum, and they appear on chromatogram as different patterns. For high-sensitivity analysis, use a septum of which bleeding does not appear in positions that interfere with the peaks of the target compounds. After extraction with hexane, etc. for a few hours, conditioning for a few hours at about 120 °C to 150 °C (less than about 200 °C for LL/HT septum) may be effective to decrease bleeding.
However, extraction with organic solvent is not required when using a CRS septum (AG3) because it is a low-bleed septum.