Teflon plunger

XI.4.2 Syringes, 2S0 pL, 500 pL, and 1 mL capacities and accurate to e nearest 1 pJL, 1 pL, and 0.01 mL, respectively. A quality, gas tigh glass syringe with teflon plunger and LEUR fittings is recommended. 

Two graduated dropping funnels of 500-ml. capacity equipped with pressure-equalizing tubes and small diameter tips to allow two solutions to be added in fine streams were used. They were also equipped with screw-in type plungers with Teflon fluorocarbon tips to allow fine adjustment of the flow rates. The checkers utilized standard 500-ml. dropping funnels and two needle valve adapters shown in Figure 1. 

S. H. Langer and P. Pantages, Anal. ( hem., 30 1889 (1958). Teflon-tipped gaslight syringes are manufactured by the Hamilton Company, Whittier, CA. "Disposable syringes with rubber-tipped plungers are manufactured by Becton, Dickinson, Co., Rutherford, NJ. 

Pumps are basically devices for pulling in solvent, pressurizing it, and driving it out through the injector, column, and detector. As described earlier, it does this with a plunger driven through a Teflon seal into a pumping chamber (Fig. 9.2). 

The first step in the wetted path in the HPLC is the solvent reservoir holding freshly filtered (and possibly degassed or deoxygenated) solvent. Most systems use a porous fritted stone (5-30-/an filter) as a solvent line sinker. The tubing to the solvent inlet is wide-diameter Teflon . In the solvent inlet line we may have another frit and a sapphire ball/stainless steel check valve. The wetted surfaces in the pumping chamber are all stainless steel except for the plunger... 

Spare parts that are needed are compression fittings and ferrules, plunger and injector rotor seals, an extra plunger and seals, column filters, and injector needle port seals. If you do not use pacification, you might want to keep a set of check valves on hand. I always have one coil each of 0.01- and 0.02-in tubing in addition to my column blank. A replacement solvent inlet line with a porous stone is useful in case of corrosion. If you filter solvents, you need cellulose, nylon, and Teflon filters. You also need a back-up lamp for your detector. 

Fig. 10 Plunger-type ultramicro buret. 1, micrometer head 2, packing gland (Teflon) 3, plunger (Kel-F, stainless steel, ruby) 4, glass reservoir 5, capillary tip (polyethylene).

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