YL Instruments YL9100 HPLC, User Manual

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YL9112 Isocratic Pump
Conditioning of high pressure seal
1) Prepare organic solvent such as iso-propanol or methanol necessary. In order to conditioning it,
use organic solvent only and do not use buffer solution and base solution.
2) Mix iso-propanol or methanol with water by 50:50, and fill instrument with it using the prime/purge
valve. And plug the outlet of pump.
3) Set the high pressure limit to 2000psi and make flow rate be 0.2ml/min at isocratic mode, and do
not make air bubble be present inside using prime/purge valve.
4) Start pump. The pressure will increase upto 2000psi and then the pump will be stopped with a
high pressure limit message. Repeat this procedure 2-3 times and then conditioning of seal is
completed.
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L9112
5-3. Replacement of plunger
If piston plunger is used for long time, it should be replaced due to wear.
The worn piston causes leakage of liquid as well as shortens life of high pressure seal. Piston wear is not
well observed visually, so care should be taken when observing it.
1) Loosen tubing of inlet check valve and outlet check valve of pump head.
2) Press pump head to main body of instrument by hand, and loosen head nut.
3) Separate pump head assembly from instrument. Then, plunger is left in the place where pump
head assembly is loosened. When loosening it, pull it carefully to the direction of pump head
guide so that high pressure seal may not be damaged due to eccentricity.
4) Pull plunger, replace it with new one at same location, and insert it.
5) If there are contaminants on surface of plunger, remove contaminant by applying methanol on
cloth without dust.
6) Arrange plunger in the manner that plunger may enter the center hole of loosened pump head
assembly, and then press pump head by hand so that head may be pressed into body. When
pressing it, press it carefully and take care so that pump head may be maintained vertical.
7) Tighten head nut with it pressed. Tighten it so that left and right sides may be same in turn, and
tighten it until it may be tightened no more by hand while confirming tightening status finally.
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