A pyrometer is a device used to measure high temperatures by detecting thermal radiation emitted from an object's surface. The first pyrometer was invented by Josiah Wedgwood to measure temperatures in his kilns. Modern pyrometers work by focusing thermal radiation onto a detector, and the detector's output signal is related to the object's temperature through Stefan-Boltzmann law. There are two main types of pyrometers: optical pyrometers which use manual measurements by comparing an object's brightness to a calibrated lamp, and radiation pyrometers which can measure higher temperatures by detecting infrared wavelengths between 0.7-20 microns.
Radiation pyrometry and temperature sensorYasin Latif
We discuss the working principle and construction of different temperature sensors like
radiation pyrometer ,filled system thermometer and bimetallic thermometer.their advantages
disadvantages and industrial application etc.
Non-intrusive Methods of Temperature Measurement ( Radiation Thermometry )rajguptanitw
A radiation thermometer is an instrument which collects radiation from a target and produces an output signal, usually electrical, related to the radiance, which is used to infer the temperature of the target.
The wavelength of maximum emission varies between 10.6 mm at 0°C and 1.3 mm at 2000C.
For most measurement applications, radiation is emitted predominantly in the visible, near- and middle-infrared regions of the electromagnetic spectrum.
A radiation thermometer is an instrument which collects radiation from a target and produces an output signal, usually electrical, related to the radiance, which is used to infer the temperature of the target.
The basic measurement system for a radiation thermometer comprises the following elements.
(1) The target of measurement.
(2) An optical system which collects and directs the radiation.
Elements of the optical system may also be used to modify the spectral response of the thermometer.
(3) A sensor which produces a signal, usually electrical, related to the incident energy flux.
(4) A reference source which may be physically situated in the instrument itself or located in a calibration laboratory.
(5) A means of signal processing and display.
An optical pyrometer consists basically of an optical system and a power supply.
The optical system includes a microscope, a calibrated lamp and a narrow band Wave filter, all arranged so that the test body and the standard light source can be viewed simultaneously.
The power supply provides an adjustable current to the lamp filament.
Optical pyrometry is based on the fact that the spectral radiance from an incandescent body is a function of its temperature.
For black body radiation, the well-known curves of Plank’s equation describe the energy distribution as a function of temperature and wavelength.
If a non-black body is being viewed ,however, its emissivity ,which is a function of wavelength and temperature, must be taken into consideration.
In general, to obtain the temperature of a test body, the intensity of its radiation at a particular wavelength is compared with that of a standard light source.
The accuracy of a temperature determination by the single-color optical pyrometer just discussed is based on black body furnace sightings or on known emissivities.
A two-color pyrometer, on the other band, is used in an attempt to avoid the need for emissivity corrections.
The principle of operation is that energy radiated at one color increases with temperature at a different rate from that at another color.
The ratio of radiance at two different effective wavelengths is used to deduce the temperature. The two-color temperature will equal the actual temperature whenever the emissivity at the two wavelengths is the same. Unfortunately this is seldom true. All that can be said is that when the emissivity does not change rapidly with wavelength, the two-color temperature may be closer to the actual temperature than the single-color brightness temperature.
If the emissivity change with wavelength is large, however, the converse is true. Kostkowski of the NBS indicates that, in any case, the two-color pyrometer is less precise than the single-color optical pyrometer.
A short study of an Optical Pyrometer- a device which is udsed to measure the temperature of an object by comparing it's luminous intensity with a reference value
Radiation pyrometry and temperature sensorYasin Latif
We discuss the working principle and construction of different temperature sensors like
radiation pyrometer ,filled system thermometer and bimetallic thermometer.their advantages
disadvantages and industrial application etc.
Non-intrusive Methods of Temperature Measurement ( Radiation Thermometry )rajguptanitw
A radiation thermometer is an instrument which collects radiation from a target and produces an output signal, usually electrical, related to the radiance, which is used to infer the temperature of the target.
The wavelength of maximum emission varies between 10.6 mm at 0°C and 1.3 mm at 2000C.
For most measurement applications, radiation is emitted predominantly in the visible, near- and middle-infrared regions of the electromagnetic spectrum.
A radiation thermometer is an instrument which collects radiation from a target and produces an output signal, usually electrical, related to the radiance, which is used to infer the temperature of the target.
The basic measurement system for a radiation thermometer comprises the following elements.
(1) The target of measurement.
(2) An optical system which collects and directs the radiation.
Elements of the optical system may also be used to modify the spectral response of the thermometer.
(3) A sensor which produces a signal, usually electrical, related to the incident energy flux.
(4) A reference source which may be physically situated in the instrument itself or located in a calibration laboratory.
(5) A means of signal processing and display.
An optical pyrometer consists basically of an optical system and a power supply.
The optical system includes a microscope, a calibrated lamp and a narrow band Wave filter, all arranged so that the test body and the standard light source can be viewed simultaneously.
The power supply provides an adjustable current to the lamp filament.
Optical pyrometry is based on the fact that the spectral radiance from an incandescent body is a function of its temperature.
For black body radiation, the well-known curves of Plank’s equation describe the energy distribution as a function of temperature and wavelength.
If a non-black body is being viewed ,however, its emissivity ,which is a function of wavelength and temperature, must be taken into consideration.
In general, to obtain the temperature of a test body, the intensity of its radiation at a particular wavelength is compared with that of a standard light source.
The accuracy of a temperature determination by the single-color optical pyrometer just discussed is based on black body furnace sightings or on known emissivities.
A two-color pyrometer, on the other band, is used in an attempt to avoid the need for emissivity corrections.
The principle of operation is that energy radiated at one color increases with temperature at a different rate from that at another color.
The ratio of radiance at two different effective wavelengths is used to deduce the temperature. The two-color temperature will equal the actual temperature whenever the emissivity at the two wavelengths is the same. Unfortunately this is seldom true. All that can be said is that when the emissivity does not change rapidly with wavelength, the two-color temperature may be closer to the actual temperature than the single-color brightness temperature.
If the emissivity change with wavelength is large, however, the converse is true. Kostkowski of the NBS indicates that, in any case, the two-color pyrometer is less precise than the single-color optical pyrometer.
A short study of an Optical Pyrometer- a device which is udsed to measure the temperature of an object by comparing it's luminous intensity with a reference value
You can learn about Vital Signs of Patient,Types of Temperature measurement, Systematic body temperature measurement, Mercury Thermometer, Thermometer, Thermocouple, Thermistor, Resistance calculation formula, Surface Temperature / Skin Temperature measurement, Infrared Thermometer, Thermovision, Thermograph, Thermogram, Coding Task
Fluke offers the latest in non-contact infrared (IR) thermometers (sometimes known as infrared pyrometers) and contact thermometers, probes, accessories, and application expertise for a complete range of temperature applications. Fluke backs all of its handheld thermometers with a no-hassle 2-year warranty and the highest level of customer service.
various types of temperature measuring instrument
1.expansion types
i)bimetallic strips
ii)liquid in gas
2.based on electric resistivity
i)thermocouple
ii)thermistors(most sensitivity)
3.pyrometers
i)mirror types
ii)optical
iii)photon types(not exact names:-based on collection of photon)
and one interesting term include in pyrometers is THERMOPILE:A large number of themocouple connected in series.Hopes so you all will enjoy
You can learn about Vital Signs of Patient,Types of Temperature measurement, Systematic body temperature measurement, Mercury Thermometer, Thermometer, Thermocouple, Thermistor, Resistance calculation formula, Surface Temperature / Skin Temperature measurement, Infrared Thermometer, Thermovision, Thermograph, Thermogram, Coding Task
Fluke offers the latest in non-contact infrared (IR) thermometers (sometimes known as infrared pyrometers) and contact thermometers, probes, accessories, and application expertise for a complete range of temperature applications. Fluke backs all of its handheld thermometers with a no-hassle 2-year warranty and the highest level of customer service.
various types of temperature measuring instrument
1.expansion types
i)bimetallic strips
ii)liquid in gas
2.based on electric resistivity
i)thermocouple
ii)thermistors(most sensitivity)
3.pyrometers
i)mirror types
ii)optical
iii)photon types(not exact names:-based on collection of photon)
and one interesting term include in pyrometers is THERMOPILE:A large number of themocouple connected in series.Hopes so you all will enjoy
A thermocouple is a temperature-measuring device consisting of two dissimilar conductors that contact each other at one or more spots. It produces a voltage when the temperature of one of the spots differs from the reference temperature at other parts of the circuit.
1. THERMOCOUPLE
∙ Principle of Operation
∙ Materials Used
∙ Advantages
∙ Applications
∙ Comparison with RTD
∙ Limitations
By
AnandBongir
GirjashankarMishra
2. A thermocouple is a junction between two different metals that produces a voltage related to a temperature difference.
3. Principle of Operation
Thermocouples are based on the principle that two wires made of dissimilar materials connected at either end will generate a potential between the two ends that is a function of the materials and temperature difference between the two ends (also called the Seebeck Effect).
4. Seebeck Effect
5.
6. Materials Used
Type K:
Chromel – Alumel
• Range: −200 °C to +1350 °C
• Sensi: 41 µV/°C
Type J:
Iron – Constantan
• −40 to +750 °C
• 55 µV/°C
Type E:
Chromel – Constantan
• 401 to 900° C
• 68 µV/°C
Type N:
Nicrosil – Nisil
• >1200 °C
• 39 µV/°C
7. Advantages
It is rugged in construction
Covers a wide temperature range
Using extension leads and compensating cables, long transmission distances for temperature measurement possible. This is most suitable for temperature measurement of industrial furnaces
Comparatively cheaper in cost
Calibration can be easily checked
Offers good reproducibility
High speed of response
Satisfactory measurement accuracy
8. Limitations
For accurate temperature measurements, cold junction compensation is necessary
The emf induced versus temperature characteristics is somewhat nonlinear
Stray voltage pickup is possible
In many applications, amplification of signal is required
9. Applications
Type B, S, R and K thermocouples are used extensively in the steel and iron industries to monitor temperatures and chemistry throughout the steel making process.
Gas-fed heating appliances such as ovens & water heaters.
In the testing of prototype electrical and mechanical apparatus
The Stroboscope was invented and improved upon by H. E. Edgerton starting in 1931. Weiber's Stroboscope is
ideal equipment for research and general applications in field of study of moving objects. Our Stroboscope is an
optical instrument that makes equipment appear to be slow or still.
We provide you Project Temperature Sensors – Types.You can choose the best of your choice and interest from the list of topics we suggested. All new project ideas that are appearing focuses to improve the knowledge of Engineering students.
https://www.elprocus.com
Visit our page to get more ideas on Project Report Format for Final Year Engineering Students these ideas developed by professionals.
Elprocus provides free verified electronic projects kits around the world with abstracts, circuit diagrams, and free electronic software. We provide guidance manual for Do It Yourself Kits (DIY) with the modules at best price along with free shipping.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Future approaches to cope with spontaneous combustionSujit Surendran
"Many researches have been made to predict and mitigate in spontaneous combustion of coal which have failed at times due improper monitoring and conventional methods of its early detection.
Here is a paper presents methods that shall be the future face of mining industry which is taking avid steps to encourage IT and other technologies to fight against such problems"
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
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2. WHAT IS PYROMETER?
A pyrometer is a type of thermometer used to measure high
temperatures. Various forms of pyrometers have historically existed. In
the modern usage, it is a non-contacting device that intercepts and
measures thermal radiation, a process known as pyrometry. The
thermal radiation can be used to determine the temperature of an
object's surface.
The word pyrometer comes from the Greek word for fire, "πυρ" (pyro),
and meter, meaning to measure. Pyrometer was originally coined to
denote a device capable of measuring temperatures of objects
above incandescence (i.e. objects bright to the human eye).
3. HISTORY/INVENTOR
The potter Josiah Wedgwood invented the first pyrometer to measure
the temperature in his kilns, which first compared the color of clay fired
at known temperatures, but was eventually upgraded to measuring
the shrinkage of pieces of clay, which depended on the heat of the
kiln. Later examples used the expansion of a metal bar.
Modern pyrometers became available when the first disappearing
filament pyrometer was built by L. Holborn and F. Kurlbaum in 1901. This
device superimposed a thin, heated filament over the object to be
measured and relied on the operator’s eye to detect when the
filament vanished. The object temperature was then read from a scale
on the pyrometer.
4. The temperature returned by the vanishing filament pyrometer
and others of its kind, called brightness pyrometers, is
dependent on the emissivity of the object. With greater use of
brightness pyrometers, it became obvious that problems existed
with relying on knowledge of the value of emissivity. Emissivity
was found to change, often drastically, with surface roughness,
bulk and surface composition, and even the temperature itself.
To get around these difficulties, the ratio or two-color pyrometer was
developed. They rely on the fact that Planck's law, which relates
temperature to the intensity of radiation emitted at individual
wavelengths, can be solved for temperature if Planck's statement of
the intensities at two different wavelengths is divided. This solution
assumes that the emissivity is the same at both wavelengths and
cancels out in the division. This is known as the gray body assumption.
Ratio pyrometers are essentially two brightness pyrometers in a single
instrument. The operational principles of the ratio pyrometers were
developed in the 1920s and 1930s, and they were commercially
available in 1939.
5. As the ratio pyrometer came into popular use, it was
determined that many materials, of which metals are an
example, do not have the same emissivity at two wavelengths.
For these materials, the emissivity does not cancel out and the
temperature measurement is in error. The amount of error
depends on the emissivity's and the wavelengths where the
measurements are taken. Two-color ratio pyrometers cannot
measure whether a material’s emissivity is wavelength
dependent.
6. PRINCIPLE OF OPERATION
A modern pyrometer has an optical system and a detector. The
optical system focuses the thermal radiation onto the detector. The
output signal of the detector (temperature T) is related to the thermal
radiation or irradiance j* of the target object through the Stefan–
Boltzmann law, theconstant of proportionality σ, called the Stefan-
Boltzmann constant and the emissivity ε of the object.
This output is used to infer the object's temperature. Thus, there is no
need for direct contact between the pyrometer and the object, as
there is with thermocouples and resistance temperature detectors
(RTDs).
7. WORKING OF A PYROMETER
There are two basic kinds of pyrometers: optical pyrometers, where
you look at a heat source through a mini-telescope and make a
manual measurement, and electronic, digital pyrometers that
measure completely automatically. Some devices described as
pyrometers actually have to be touching the hot object they're
measuring. Strictly speaking, instruments like this are really just high-temperature
thermometers based on thermocouples .Since they
don't measure temperature at a distance, they're not really
pyrometers at all.
8. A Pyrometer, or radiation thermometer, is a non-contact
instrument that detects an object's surface temperature by
measuring the temperature of the electromagnetic radiation
(infrared or visible) emitted from the object.
The wavelength of thermal
radiation ranges from 0.1 to
100 μm (4 ~ 4,000 μin), i.e.,
from the deep ultraviolet (UV)
across the visible spectrum to
the middle of the infrared
region (IR).
9. Pyrometers are essentially photodetectors which are capable of
absorbing energy, or measuring the EM wave intensity, at a
particular wavelength or within a certain range of wavelengths.
10. TYPES OF PYROMETERS
The following are some of the most commonly and widely used pyrometers
OPTICAL PYROMETER
RADIATION PYROMETER
11. OPTICAL PYROMETER
The Optical Pyrometer is a highly-developed and well accepted
noncontact temperature measurement device with a long and varied
past from its origins more than 100 years ago. In spite of the fact that more
modern, automatic devices have nearly displaced it, several makers still
produce and sell profitable quantities each year.
In general, opticals, as they are often called, can be described as fitting
into two seperate types, according to the two USA companies that
produce them. However, there are actually several different types that
vary in compexity and cost. A quick review of the descriptions below will
provide some of the differences and a check of the web sites of the two
companies will yield even more information. We suspect that there are
other makers overseas and we are looking to find more details about
them and their web presence.
12.
13. WORKING OF A OPTICAL PYROMETER
Optical Pyrometers work on the basic principle of using the human eye
to match the brightness of the hot object to the brightness of a
calibrated lamp filament inside the instrument. The optical system
contains filters that restrict the wavelength-sensitivity of the devices to
a narrow wavelength band around 0.65 to 0.66 microns (the red region
of the visible spectrum).
Other filters reduce the intensity so that one instrument can have a
relatively wide temperature range capability. Needless to say, by
restricting the wavelength response of the device to the red region of
the visible, it can only be used to measure objects that are hot enough
to be incandescent, or glowing. This limits the lower end of the
temperature measurement range of these devices to about 700 °.
Some experimental devices have been built using light amplifiers to
extend the range downwards, but the devices become quite
cumbersome, fragile and expensive.
14. Modern radiation thermometers provide the capability to measure
within and below the range of the optical pyrometer with equal or
better measurement precision plus faster time response, precise
emissivity correction capability, better calibration stability,
enhanced ruggedness and relatively modest cost.
15.
16. ADVANTAGES
Simple assembling of the device enables easy use of it.
Provides a very high accuracy with +/-5 degree Celsius.
There is no need of any direct body contact between the optical
pyrometer and the object. Thus, it can be used in a wide variety of
applications.
As long as the size of the object, whose temperature is to measured fits
with the size of the optical pyrometer, the distance between both of
them is not at all a problem. Thus, the device can be used for remote
sensing.
This device can not only be used to measure the temperature, but can
also be used to see the heat produced by the object/source. Thus,
optical pyrometers can be used to measure and view wavelengths less
than or equal to 0.65 microns. But, a Radiation Pyrometer can be used
for high heat applications and can measure wavelengths between
0.70 microns to 20 microns.
17. DISADVANTAGES
As the measurement is based on the light intensity, the device can
be used only in applications with a minimum temperature of 700
degree Celsius.
The device is not useful for obtaining continuous values of
temperatures at small intervals.
18. RADIATION PYROMETER
As discussed earlier, an Optical Pyrometer can be not only be used
for temperature measurement, but also can be used to see the heat
that is measured. The observer is actually able to calculate the
infrared wavelength of the heat produced and also see the heat
patterns by the object. But the amount of heat that the device can
sense is limited to 0.65 microns. This is why the radiation pyrometer is
more useful, as it can be used to measure all temperatures of
wavelengths between 0.70 microns and 20 microns.
19. The wavelengths measured by the device are known to be pure
radiation wavelengths, that is, the common range for radioactive
heat. This device is used in places where physical contact temperature
sensors likeThermocouple, RTD, and Thermistors would fail because of
the high temperature of the source.
The main theory behind a radiation pyrometer is that the temperature
is measured through the naturally emitted heat radiation by the body.
This heat is known to be a function of its temperature. According to the
application of the device, the way in which the heat is measured can
be summarized into two:
Total Radiation Pyrometer – In this method, the total heat emitted
from the hot source is measured at all wavelengths.
Selective Radiation Pyrometer – In this method, the heat radiated
from the hot source is measured at a given wavelength.
20.
21. WORKING OF A RADIATION PTROMETER
the radiation pyrometer has an optical system, including a lens, a
mirror and an adjustable eye piece. The heat energy emitted from
the hot body is passed on to the optical lens, which collects it and is
focused on to the detector with the help of the mirror and eye
piece arrangement. The detector may either be a thermistor or
photomultiplier tubes. Though the latter is known for faster detection
of fast moving objects, the former may be used for small scale
applications. Thus, the heat energy is converted to its corresponding
electrical signal by the detector and is sent to the output
temperature display device.
22. ADVANTAGES
The device can be used to measure very high temperatures without
direct contact with the hot source (Molten metal).
The biggest advantage is that the optical lens can be adjusted to
measure temperature of objects that are even 1/15 inch in
diameter and that too kept at a long s=distance from the
measuring device.
The sight path of the device is maintained by the construction of
the instrument components, such as the lens and curved mirrors.
23. APPLICATION
Pyrometers are suited especially to the measurement of moving
objects or any surfaces that can not be reached or can not be
touched.
Smelter Industry
Temperature is a fundamental parameter in metallurgical furnace
operations. Reliable and continuous measurement of the melt
temperature is essential for effective control of the operation.
Smelting rates can be maximized, slag can be produced at the
optimum temperature, fuel consumption is minimized and refractory
life may also be lengthened. Thermocouples were the traditional
devices used for this purpose, but they are unsuitable for continuous
measurement because they melt and degrade.
24. Over-the-bath Pyrometer
Salt bath furnaces operate at temperatures up to 1300 °C and are
used for heat treatment. At very high working temperatures with
intense heat transfer between the molten salt and the steel being
treated, precision is maintained by measuring the temperature of
the molten salt. Most errors are caused by slag on the surface which
is cooler than the salt bath.
Tuyère Pyrometer
The Tuyère Pyrometer is an optical instrument for temperature
measurement through the tuyeres which are normally used for
feeding air or reactants into the bath of the furnace.
25. Steam boilers
A steam boiler may be fitted with a pyrometer to measure the
steam temperature in the superheater.
Hot Air Balloons
A hot air balloon is equipped with a pyrometer for measuring the
temperature at the top of the envelope in order to prevent
overheating of the fabric.