2 Replies Latest reply on Sep 17, 2016 6:20 AM by daweilmsms

    QTOF Flight Tube - Is It Heated and Why?

      HI All,


      I heard from a friend that the flight tubes on Agilent QTOF instruments are heated a little bit - default being around 40 deg C. It this true? If so, why are they heated? Is this something that people used to do with older systems, but not newer ones for some reason?


      I understand  the flight tubes are made of INVAR metal because it's got the lowest coefficient of thermal expansion of any metal - perfect for maintaining a consistent flight path length. Why would they need to be heated?


      It sounds like there is a story for why this metal is used and why it may be heated. Does anyone know?


      Thanks! - Josh

        • Re: QTOF Flight Tube - Is It Heated and Why?

          Hi Josh,


          Agilent engineers may heat the flight tube with a jacket at installation. This improves the initial pump down times on Agilent TOF and QTOF systems, especially in humid environments. After installation the jacket is removed.


          The INVAR material does have a low thermal coefficient of expansion and in addition to that, the flight tubes also insulated by a vacuum sleeve. This acts like a thermos flask and insulates the flight tube from a lot of lab temperature fluctuations. With these two things combined, there is little need to heat the flight tube above ambient temperature for normal operation.





            • Re: QTOF Flight Tube - Is It Heated and Why?

              Hello Josh


              I wanted to clarify something that you mentioned in the question.  The comment about heating to 40oC is that the high voltage power supply electronics are heated to 40oC separate from the flight tube.


              That is where the 40oC comes into function on the TOF and QTOF product line.




              David A. Weil, Ph.D.

              Senior Applications Scientist Agilent Technologies

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