6
Intended use
Intended use
HPLC
High-pressure liquid chromatography (HPLC) is a method
for separating substance mixtures, determining substances,
and measuring their concentration.
The device or system is suitable for high-pressure liquid chroma-
tography. It is suitable for laboratory use, for analyzing sub-
stance mixtures that can be dissolved in a solvent or solvent
mixture.
Injection valves,
multiposition valves,
and
electrical
valve drives
Injection valves or multiposition valves are used in the HPLC to
bring in the sample from the sample loop in the pump's high
pressure flow, so that the sample is transported to the column.
The sample is fed in at atmospheric pressure in the sample loop
by a syringe or via feed pump from a sample reservoir.
Injection valves can have 2 or 3 channels, which depends on
the rotor seal. Multiposition valves are 1-channel valves.
Overview valves and valve drives
Valves and valve drives are always completely assembled and
tested when they leave the factory. The following components
may be included:
Fig. 1
Overview valves and valve drives
Main areas of
application
Main areas of application for multichannel valves are the injec-
tion or column switching, the column backflushing, sample
accumulation, or the alternating sample accumulation. Multi-
channel valves are used for example to select different solvents
(solvent selection valve) without having to reestablish the con-
nections anew or laying out the capillaries again.
Single-channel valves are employed for fractioning if the form
and the size of the fraction containers should be freely select-
able. By combining a maximum of eight single-channel valve,
up to 120 positions can be used for fractioning in applications
in preparative HPLC.
Legend
A. Mounting plate
B. Valve drive
C. Mounted, electrical
injection valve
D. Valve holder for
pumps or detectors
E. Electrical injection
valve
F. Hand injection valve
A
B
C
D
E
F
