YL Instruments YL9100 HPLC, User Manual

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YL9112 Isocratic Pump
change all seals of both head when change seal due to long use. Leaked solvent flows out through
washing port.
Change of high pressure seal
1) Loosen tubing of inlet check valve and outlet check valve of pump head.
2) Loosen two head nut for each head using spanner.
3) Separate pump head assembly from instrument.
At this time, plunger is left at the place where pump head assembly was loosened. When
loosening it, pull it carefully in pump head guide direction and take care not to damage plunger.
4) If backup washer in back side of pump head is pulled out, low pressure seal assembly appears.
Use seal insertion/removal tool to separate low pressure seal assembly. Then, high pressure seal
appears inside of head.
5) Remove worn seal with seal insertion/removal tool and insert new high pressure seal prepared at
that place using seal insertion/removal tool in the same manner. Direction of seal should be such
that the direction to see O-ring is toward front of head. Be careful not to change direction.
6) Insert low pressure seal assembly and backup washer.
7) Arrange pump head so that plunger left at the place where it is loosened be inserted into center
hole of pump head assembly, and then press pump head to main body by inserting pump head by
hand. When pressing it, press it carefully so that pump head may be maintained horizontal.
8) Tighten head nut in pressed condition. Tighten it so that left side and light side may be same, and
tighten it until it is tightened no more by hand while confirming status of tightening finally.
9) Replace high pressure seal by applying the process of 1) to 8) to pump head of opposite side.
[Fig. 14] Replacement of high pressure seal
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