Pressure measurement at a very high Temperature

Hello Guest,

1. How much does the pressure fluctuate?
2. How often does your system need to know what the pressure is?

A non-insulated tube with sufficient ID and far enough away from the process would give you good pressure measurement as long as pressures are not wildly fluctuating quickly. If the process vessel is insulated, a 2-foot section of 1/4" tubing should be enough to keep the PT below its max temp constraints in STP conditions.

Mike

is there any volatile in the process stream that will condense/solidify in the cool loop? If so, make the loop uphill, so it will drain back. Even a capillary tube will suffice if the process stream is gaseous.

Beware of condensation, this is a common problem in my experience when dealing with hot lines. We had it happen in flue gas applications and steam applications where we would either condense liquid in the impulse lines or precipitate solids. We had to modify our standard instrumentation installation to deal with these problems.

PT we are using cann' withstand temp more than 85 deg cen.?? Do you mean Thermocoule? what type are you using?

I believe here you use an "R" Type with ceremic well to withstand such high temperature.

I believe by PT Sushant Chanana you mean Pressure Transducer.

Brad

From the information provided, my take is that if you are interested in slowly changing pressures, you can use a coil of stainless steel tubing to connect the transducer to the process (as long as the coils don't touch each other). If pressure transients are to be measured, or rapid dynamic response is required, the nature of the problem changes and you will need to do some engineering.

Alternate solutions.

1) Instead of using impulse tube, utilize know metal with calculated thermal expansion.

http://www.engineeringtoolbox.com/thermal-expansion-metals-d_859.html

Measure thermal expansion. Here's an example solution site.

http://www.flexial.com/sensors.html

then calculate pressure from expansion rate.

When looking at these types of problems, from a management and maintenance view, look into simple solutions requiring minimum maintenance.

2)Use infrared camera to calculate pressure.

http://www.dias-infrared.de/index.php/index.php?lang=en