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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal">Have any of you with older machines ever replaced your rotors? Our AN60 is 20 years old, and our AN50 is 14. Beckman recommends replacement after 12 years or 6000 runs. Are there any signs of a declining rotor short of catastrophic failure?
Do you think Beckman considers the length of AUC runs when specifying 6000 runs? A previous post suggested de-rating the maximum speed of the rotor by 10% and then staring the lifetime count anew. Obviously, replacement expenses would be nice to avoid, but
I want to make sure we are not risking compromising the instrument.<o:p></o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Debbie<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Debbie Eckert, Ph.D.<o:p></o:p></p>
<p class="MsoNormal">Research Assistant Professor<o:p></o:p></p>
<p class="MsoNormal">University of Utah School of Medicine<o:p></o:p></p>
<p class="MsoNormal">Dept of Biochemistry<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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