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seal calibration passed!!!! But suspicious about numbers

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

4 posts Page 1 of 1
up seal-360

down seal-70

seal width-40



the up seal numbers don't seem right, but the test passed (717 plus autosampler Waters LC) , do higher numbers indicate a better seal or a worse off seal? Should I move the needle platform more upwards or downwards?
as far as I remeber:
The numbers are steps of the needle motor, so in fact give the position of the upper and lower seal.
Nothing to do with sealing quality. For this, use the compression check (>purge injector, use a column for backpressure when purging injector and compression check).

The seal width is the space between the seals, where the needle is in place for injection and during the whole run.

If compression check is ok, you should be fine.
as far as I remeber:
The numbers are steps of the needle motor, so in fact give the position of the upper and lower seal.
Nothing to do with sealing quality. For this, use the compression check (>purge injector, use a column for backpressure when purging injector and compression check).

The seal width is the space between the seals, where the needle is in place for injection and during the whole run.

If compression check is ok, you should be fine.
the compressibility test did not pass, got the message "compressibility exceeds limit", tried the valve tests and all of them seem to work out just fine.
btw, with all due respect, the "up seal count" still seems a bit skewy to me, compared to the numbers that I see online....
4 posts Page 1 of 1

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