GC INJECTORS Model 8640 20-Vial Integrated Liquid Autosampler Overview The SRI Model 8640 20-vial liquid autosampler is installed on the left-hand side of the SRI 8610C GC. The 8640 connects to an additional injector on the left side of the column oven. This additional injector may be on-column, heated, or split/splitless. It uses a sample tray to hold up to twenty 2mL vials, a sample probe to transfer the sample from the vials into the syringe barrel, and an injection mechanism to deliver the sample from the syringe barrel, through the needle, into the injector in the GC column oven wall. The 8640 uses 60psi of air or nitrogen to actuate its moving parts. The 8640 functions are assigned relays so that the autosampler may be operated automatically using a PeakSimple event table. The 8640 is shipped with 100 screw-top vials and septa, replacements for which are available from a variety of suppliers. Extra sample trays and cooled sample trays are available. The cooled sample trays require an external refrigerated lab circulator. Sample probe assembly TeflonTM waste line Protective cover Sample tray Waste bottle Pneumatic lines (bundle of six) 8640 with the protective cover removed Sample probe piston Waste bottle Knurled thumbscrew Needle Syringe barrel Split/splitless injector in GC column oven wall Injection mechanism Needle guide with waste diverter valve Injection piston Syringe piston Sample tray Additional vials are available from Alltech Associates, Inc. 15x45mm Clear Vial Kit: 100 clear vials with TFE/Silicone liners Alltech part # 98008 800-255-8324 www.alltechweb.com

GC INJECTORS Model 8640 20-Vial Integrated Liquid Autosampler Theory of Operation Liquid sample is sealed into vapor-tight vials which are inserted into the sample tray. The tray is then inserted into the Model 8640 assembly and positioned for the sampling sequence. The 8640 uses 60psi of air or nitrogen to actuate its moving parts. Sampling Probe Sequence The sampling probe, a concentric needle, is moved down by a piston to pressurize the vial with helium or other gas, causing sample to flow through the injection syringe and out the TeflonTM tubing into the waste bottle. The sample probe pressurizes...

GC INJECTORS Model 8640 20-Vial Integrated Liquid Autosampler 1. Fill each 2mL vial at least 75% full with liquid sample. Close the vials so that they are vapor-tight, with the Teflon side of the vial septa facing downward into the vial. 2. The sample tray is inserted and removed from the 8640 in one direction only. To remove the sample vial tray, push it away from you, toward the back of the GC, until it is free of the autosampler assembly. Place the filled sample vials in the tray. Reinsert the sample tray into the 8640 assembly from the front. Push it gently toward the back of the GC until...

GC INJECTORS Model 8640 20-Vial Integrated Liquid Autosampler Changing the Needle In the course of normal operation, the 8640 sample injection needle may become bent or otherwise damaged and require Sample probe replacing. Make sure the Needle guide with assembly syringe mechanism is fully waste diverter valve and knurled thumbscrew retracted before starting; Waste bottle this is the default position to which it should return after a sample injection sequence. Replacement needles Needle TeflonTM are available from Central bushings Instruments under part number 502743. Syringe barrel and needle...