All,
We have been having a sample breakage problem the last couple of weeks. Its
very intermittent and occurs with different students/different tube brands,
etc. For instance, a student inserts a sample, has trouble
locking/shimming/spinning, and then ejects the sample. They find that their
sample has broken. When I get on the scence I remove the probe and take a
look. In each case the tube breaks at the top of the probe. The tube
remains intact inside the probe. In the past 2 weeks we've had 4 of these
breakages. No changes were made to air/spinner/probe/etc prior to these
occurances.
I marked a tube with black ink and checked for scoring marks. A scoring
mark appeared around the same place where the breakage occurs with repeated
spin on/spin off, as I suspected. I realigned the probe and the upper
barrel, however, samples are still breaking.
It seems to me it has to be an air problem. The sample must break when the
spinning begins rather than hit the bottom too hard. Anyone have a
suggestion to trouble-shoot this problem?
Thanks in advance,
Tanya
--------------------------------
Tanya L. Young, Ph.D.
Senior Scientist
Department of Chemistry
Kansas State University
Manhattan, KS 66506
office: CB 126
phone: 785-532-6477
email: tyoung_at_ksu.edu
Received on Tue Jun 24 2003 - 13:53:50 MST