we want to measure pressure. It involves following proc cond.

press: 1 mm HgA.

Bp: 144 deg @1 mmHga

Solidification: 139 deg c

Rseal may not be able to meas 1 mmHgA & have to us 1/2" APT , temp 0 -120 limit

How to meas press @xtr end w/o choking.

Thanks
iconcnl [at] vsnl.net

 

Sounds like you have a real problem there, I assume it's something like molten sulfur. A remote seal won't work, can you purge the impulse tube with air? If you connect your impulse line to the top of the process line and bleed in a little air it should keep the line clear.

Regards,
Roy

 

Do you have calculations for amount of little air flow rate required & pressure we want to measure.

 

No, not with the little bit of information you have given me. Since your system is running under a vacuum. I would think provided the impulse tubing is kept hot where it joins the process pipe any small flow at all should keep the product out of the impulse line. As I said the impulse line should be on top of the process line so any product tends to run back into line. Send me a PM at roy_matson at yahoo dot ca if you don't want to post details here.

Regards
Roy

 

Dear Roy,

At this pressure , non-condensible load estimated is only 2 Kg/Hr. We can provide only N2 to the system , we can not provide even the liquid seal.

Height is required 10 mt, if use water. but it will evaporate immediately at this pressure/Temp.

we can not use mercury for liquid seal.

Do you know any rotameter manufacturer with DP REGULATOR with lowest range of flow capacity.

We are allowed to purge N2 only 0.1 kg/Hr [ 3.5Kg/cm2g]. I have to also Kill this pressure from 3.5 kg/cm2 to lowest possible with 1.2 mm
restriction orifice plates [ adds to joint ].

Any calculations available for leakage estimate?
Any manufacturer give regulator with such low capacity flow?

We could not get through your email , if you can give me the email again ?