Selection of the outer protective tube for thermal resistors
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Our factory is constructing a new project for the vaporization of liquid chlorine; there are pipes carrying chlorine gas and liquid chlorine that require temperature monitoring, with temperatures typically ranging from 50 to 60 degrees. The drawings specify the use of HC material, but I think it’s a bit wasteful – 304 steel lined with PTFE would be a better choice F4？ Or just introduce one.) That will do. I’m not sure if it’s feasible. Of course, setting aside the issue of whether it’s my responsibility if something goes wrong after installation and design. Just a technical discussion – experts, please share some experience
PTFE-lined ones should work; those made of chlor-alkali materials might also work, and Monel could be an option as well.
It should be lined with PTFE; F4 has poor welding properties.
What is the pressure? Generally, it’s possible. For a new factory, it’s best to consult with a design institute and make some adjustments; if the quantity isn’t too large, changes aren’t recommended
50-60 degrees, positive pressure; fluorinated lining can be used
For the liquid chlorine vaporization process, it is recommended to use PTFE-lined materials, as they are cost-effective and have a long service life.
I’m particularly interested in knowing the type and material of the chlorine flow meter used on your end; could you share that information?
Without a flow meter, the entire system doesn’t require one
We initially used E+H vortex flow meters for measuring chlorine flow; the sensors in these meters were made of 316L material, while the components related to them were made of Hastelloy. After being in use for some time, the meters had to be shut down for maintenance for a few days, and a substance seeped out from the sensor area (it wasn’t chlorine, but a brown-colored unknown substance). Upon disassembly and inspection, a green layer was found on the interior of the sensor as well as on its surrounding parts. The sensor didn’t show significant signs of corrosion. Our technical team said that the green substance was nickel chloride. Later, as the required flow measurement range increased, we replaced those flow meters with ones featuring rotors coated with PTFE.
Even for F4 lining, the casing material should preferably be resistant to chlorine corrosion