Re: MFC's
Posted: Thu Mar 09, 2006 12:34 pm
For MFCs of high flow rate, (most often encountered surplus from old, torn down fab lines), you might not be able to get a slow enough DC controlled flow rate. Electronically "bumping" an MFC is possible rather than hoping the thing responds well or linearly to a .003 volt dc signal. Where there is a will, there is usually a way.
The great thing about a formal MFC is that they are made to come out of the chute metering gases and are not gas kludges.
Some MFCs can be had very inexpensively, as mentioned above, from old fab lines at surplus, but you have to watch out for what gas they passed in a former life and check for possible massive residues which might have reacted with internal components and lines.
Richard Hull
The great thing about a formal MFC is that they are made to come out of the chute metering gases and are not gas kludges.
Some MFCs can be had very inexpensively, as mentioned above, from old fab lines at surplus, but you have to watch out for what gas they passed in a former life and check for possible massive residues which might have reacted with internal components and lines.
Richard Hull