Dear Swapnil: Just to inform you that, installation used and mentioned in this thread works very well & temperature at pressure transmitter end is less than the permissible limits of transmitters. Even the temp is 1500 DEG C, should not matter much with this limits, unless Catch pot can not withstand this high temp. use the same MOC of your reactor.


Dear Richard: Just to know one point for NAK filled transmitters. what is solidification point for this fill? what additional arrangement is required to avoid solidification of this fill fluid?

I would really appreciate your feedback , we tried to locate this datasheets of transmitter[taylor Instruments], but this was long ago.

Regards
Jari
iconcnl [at] vsnl.net

 

To measure the desired pressure through PT we must keep the Tx enough away in atmosphere (ambient temp) with a condensate pot with cooling water jacket. U shall get the desired pressure.

 

hi,

May i know that which formulae you're used to infer this 3M length?

 

The Kulite paper cited above, that provides calculations for using impulse tubing to isolate pressure transmitters has a new URL:
http://www.kulite.com/docs/technical_papers/AN8401HeatTube.pdf
(take out any spaces the forum inserts into the URL)

 

The Kulite paper is a good start for a conservative estimate for external fittings.

If you include radiation effects, etc. and require that the measured fluid contain no condensibles, the 0.50" od / 0.035" wall, stainless tubing with a 2000F source will drop the temperature to 120F in 6", but that is impractically short, would recommend at least twice the Kulite rec for safety...

The more important issue is the temperature of the connection where it penetrates the equipment wall. Typically the shell temp is a lot less that the interior of the furnace.

 

Can we go in for alternate method like measuring back pressure of an inert fluid. Say instead of measuring the vessel pressure directly, we inject air at specified pressure. With the increase in vessel pressure back pressure will also increase proportionately thus giving the true pressure. Its just a raw idea. We can refine it and implement it.