Solvent delivery systems reciprocating-piston pumps

Although several systems are available that meet these requirements, the most common is the reciprocating or piston pump. The choice of solvent delivery system depends on the type of separation to be performed ... 

There are three main designs of solvent delivery system (a) the reciprocating piston pump which may be of the single, dual or triple head design (b) the syringe or displacement design which delivers constant non-pulsating flow (c) the constant pressure or pneumatic pump. 

Figure 5.3. An example of the proportioning accuracy of a reciprocating-piston pump in the composition range 0-10% B in 1% increments (A). The influence of the design of the solvent delivery system on gradient shape (B). The Broken line describes the set gradient and the solid line the gradient delivered to the column inlet. The dwell time is marked as tp.

SolV6nt Delivery. The function of the solvent delivery system is to deliver the mobile phase (eluent) through the chromatograph, accurately and re-producibly. The most popular are reciprocating-piston pumps, usually with two... 

The most important parts of the instruments are the pumps for maintaining constant, pulseless rates of flow, the column types for the molecular weight range of analysis, and the detector system see Table 3.12. Some of the popular types of solvent delivery pumps include syringe pumps, the plunger of which is actuated by a screw-fed stepper motor, and the dual piston reciprocating pumps, which may have the pistons in either series or parallel see Figure 3.19 (79). 

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