The medium to be measured is a process gas containing hydrogen, nitrogen, coke oven gas, and other gases, at a temperature of approximately 350°C and a pressure of 3.5 bar gauge at the measurement point. I can't give the detailed description of the gas composition, as it varies during different process phases. It's also a moist gas, and the humidity level can also vary during the individual process phases. Does this Pitot Tube flow meter works for me?

Mod Note: Product link removed.

 

Since the item says that it's for the range -40°C to +150°C, what would your guess be?

Aside from that, you don't give any indication of what the flow rate that you are wanting to measure, nor does the item say what range of flows it can handle. So how can you expect someone here to know if it would work for you.

Have you requested a data sheet from the manufacturer?

 

The medium to be measured is a process gas containing hydrogen, nitrogen, coke oven gas, and other gases, at a temperature of approximately 350°C and a pressure of 3.5 bar gauge at the measurement point. I can't give the detailed description of the gas composition, as it varies during different process phases. It's also a moist gas, and the humidity level can also vary during the individual process phases. Does this Pitot Tube flow meter works for me?

Mod Note: Product link removed.

Thank you! I included a link and it was removed. It's this product https://metlaninst.com/p/pitot-tube-gas-flow-meter-mtkb-201x/

 

The page stated -40 TO 150 °C and the sales told me they can customize the meter to 350°C. I‘ll request the datasheet. Thank you!

 

To monitor the flow of a hot product a common approach is to use an orifice and a differential pressure sensor to measure the pressure drop across that orifice. The differential pressure sensor lines can be a suitable length to allow cooler gas at the sensor location. Caution is needed because there is a time delay in the sensor response with this scheme, AND the sensor is not really protected from any corrosive effects of the gas.
Adding some clarification, this would be an alternative to the Pitot tube method, and is probably a bit more accurate. A Pitot Tube depends on the velocity at that point, not mass flow. Of course, all mass flow measurements depend on the density of the fluid being measured.

(30 November Addition) An adequate description of the process gas would have been: "HOT 350 °C , humid, and possibly a bit toxic." That tells us what is needed to handle, and the caution level required, without giving away any secrets.

 

You might want to look at a (here’s the only datasheet I could find) differential pressure transmitters (DP) flow setup instead of a pitot tube, especially for 350 °C gas. DP transmitters are often used for hot gases like COG because the primary element stays in the hot line while the transmitter can be mounted remotely in a cooler area. They also handle mixed-gas density changes more reliably when temperature and pressure compensation is applied.

It’s always a good idea to compare datasheets to make sure the transmitter meets your specific requirements.

Hope this helps with your setup!

 

You might want to look at a (here’s the only datasheet I could find) differential pressure transmitters (DP) flow setup instead of a pitot tube, especially for 350 °C gas. DP transmitters are often used for hot gases like COG because the primary element stays in the hot line while the transmitter can be mounted remotely in a cooler area. They also handle mixed-gas density changes more reliably when temperature and pressure compensation is applied.

It’s always a good idea to compare datasheets to make sure the transmitter meets your specific requirements.

Hope this helps with your setup!

The TS ABSOLUTELY needs to look at the data sheets before selecting a differential pressure measuring device.!!!!!
One additional comment is that within my part of the industry, a "Transmitter" device was describing a CURRENT LOOP mode sensor ONLY. So the selection of output modes will depend on what sort of data connection is in use in the attached, or proposed, control or monitoring system. The three common sensor output formats I have used are: "Full strain gage bridge 4-wire", 4-20 mA current loop, and "internal amplifier 0 to 10volt output". ALL of these schemes require additional power source and signal processing interface hardware.
And a second comment is that the pressure connections between the orifice and the DP sensor must be long enough to assure that the DP sensor temperature range is not exceeded. That requirement must be supplied to those actually assembling the system.