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Temperature Gauge good for 2500 deg C 3
- Thread starter richissa
- Start date
JohnRBaker
Mechanical
The only thing that I've ever heard of that can read temps that high are based on spectral analysis, and while there are lots of devices that reads infrared radiation, I suspect that at 2500˚C, we're way past infrared.
John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
EdStainless
Materials
There are many optical units that will measure in this range.
Most of them are 'two color' or ratio instruments that compare the intensity in two discrete wavelength band near each other.
This helps correct for emissivity and partial occlusion issues.
Such as
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
Most of them are 'two color' or ratio instruments that compare the intensity in two discrete wavelength band near each other.
This helps correct for emissivity and partial occlusion issues.
Such as
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
JohnRBaker
Mechanical
Apparently things have changed. Years ago, I was looking at infrared thermometers, and 1000˚C was the limit, although I did find one that it was claimed to be good to 1600˚C (I was not going to use it anywhere near those temps, just that I recall the specs). That being said, I just found a vendor who claims to have infrared devices that will read up to 8000˚C:
John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:
The secret of life is not finding someone to live with
It's finding someone you can't live without
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2
- #7
TugboatEng
Marine/Ocean
Tungsten-rhenium alloy thermocouples, type W can operate in that temperature range.
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1
- #8
EdStainless
Materials
So the emission curve follows a known form, fourth order I believe.
They don't emit anything.
They just measure in two bands.
The software knows that the ratio of these should exactly tell you the temperature.
By using bands that are fairly close you can assume that e is the same for both and that any blockage (occlusion, smoke, fumes) will have equal impact on both.
We used these for melting high temp alloys since the surface of melt was always changing and fumes were an issue.
Much better than old total radiation units.
There is also a very clever unit that uses a sapphire rod with the end cut at 45deg and gold plated.
They then connect it to a fiber optic bundle and do the same ratio math.
The beveled end gives you total internal refection and it follows the Black Body laws almost perfectly.
You could look at type C or D thermocouples, don't use type G.
These require a very low oxygen and low H2O environment.
I have only ever seen then used in pure hydrogen or high vacuum (<0.1 micron).
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
They don't emit anything.
They just measure in two bands.
The software knows that the ratio of these should exactly tell you the temperature.
By using bands that are fairly close you can assume that e is the same for both and that any blockage (occlusion, smoke, fumes) will have equal impact on both.
We used these for melting high temp alloys since the surface of melt was always changing and fumes were an issue.
Much better than old total radiation units.
There is also a very clever unit that uses a sapphire rod with the end cut at 45deg and gold plated.
They then connect it to a fiber optic bundle and do the same ratio math.
The beveled end gives you total internal refection and it follows the Black Body laws almost perfectly.
You could look at type C or D thermocouples, don't use type G.
These require a very low oxygen and low H2O environment.
I have only ever seen then used in pure hydrogen or high vacuum (<0.1 micron).
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
2500 Cis about 2773 K which puts the peak of spectral distribution at about 1.1 um, which is SWIR. So any SWIR (InGaAs) sensor could deal with this temperature
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
richissa,
What is your minimum temperature reading?
There is supposed to be a gadget that runs current through a wire so that it glows. You adjust the current so that it matches whatever is glowing in the background, and you read your temperature off the dial.
--
JHG
What is your minimum temperature reading?
There is supposed to be a gadget that runs current through a wire so that it glows. You adjust the current so that it matches whatever is glowing in the background, and you read your temperature off the dial.
--
JHG
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