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Types of thermometer

Types of thermometer – post 1

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Types of thermometer

Thermometers design to measure temperatures in industrial and home systems. In this paper, we introduce the standard  Types of thermometer in the industry.

mercury thermometer

The mercury-in-glass or the mercury thermometer designed by physicist Daniel Gabriel Fahrenheit in Amsterdam (1714).

It consists of a bulb containing mercury attached to a glass tube of narrow diameter; the volume of mercury in the tube is much less than the volume in the bulb.

The volume of mercury changes slightly with temperature; the small change in volume drives the narrow mercury column a relatively long way up the tube. The space above the mercury can be filling with nitrogen gas or it may be at less than atmospheric pressure, a partial vacuum.

Alcohol Thermometer

The most common liquid used in common household thermometers used to be mercury, but because of that material’s toxicity, In summary, it replaced by alcohol or ethanol.

Also An alcohol thermometer is a small sealed tube made of glass that has a small hollow bulb on one end and a thin capillary opening running through the length of its center.

The bulb and connected capillary chamber filled partly with ethanol and partly with nitrogen and ethanol vapors.

Enough alcohol places in the bulb so that at normal room temperatures it will extend into the narrow column. Along the length of the column, the tube is graded with several marks showing the temperature of the liquid at certain volumes.

Beckmann Differential Thermometer

The Beckmann differential thermometer used for measuring small differences in temperature, having a readability of around 0.001°C.

This makes it useful for the determination of melting points, boiling points, and calorimetry. Today it is superseded by sensitive digital thermometers using thermocouples, thermistors, etc.

Bimetallic Thermometer

It’s made up of two different metals bonded together, which expand by different amounts as they heat up. As the temperature changes, the bimetallic strip curves more or less tightly (contracts or expands) and the pointer, attached to it, moves up or down the scale.

Galileo thermometer

A Galileo thermometer (or Galilean thermometer) is a thermometer made of a sealed glass cylinder containing a clear liquid and several glass vessels of varying density. As the temperature changes, the individual floats rise or fall in proportion to their respective density and the density of the surrounding liquid.

Galileo thermometer used because he discovered the principle on which this thermometer base—that the density of a liquid changes in proportion to its temperature.

Infrared Thermometer

On its most basic design, an infrared thermometer consists of a lens to focus the infrared (IR) energy on to a detector, which converts the energy to an electrical signal that can display in units of temperature after being compensated for ambient temperature variation.

This configuration facilitates temperature measurement from a distance without contact with the object to measure.

As such, the infrared thermometer is useful for measuring temperature under circumstances where thermocouples or other probe type sensors cannot be used or do not produce accurate data for a variety of reasons.

Some typical circumstances are where the object to measure is moving; where the object surround by an EM field, as in induction heating; where the object contain in a vacuum or other controlled atmosphere; or in applications where a fast response is required.

Liquid crystal thermometers

Thermochromic Liquid Crystals (LCs) can be highly temperature sensitive, change to many colors, and are more expensive than leuco dyes.

LCs start black below their temperature range, go through the colors of a rainbow, and back to black again above the temperature range. LCs are reversible in that they can use over and over again. The picture shows an example of a liquid crystal sheet in response to warming.

Popular liquid crystal applications include medical devices, forehead, aquarium and room thermometers, promotional pieces and advertising applications.

Additionally, functional devices such as a propane tank gas level indicator are achieving much notoriety.

Liquid crystal thermometer strips use for thermal mapping and other industrial applications where custom inexpensive temperature monitoring is warranted.

We offer a wide range of liquid crystal thermometers as stock products, but also offer literally thousands of custom products for your label.

Unit of Temperature

Unit of Temperature

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Unit of Temperature

In this article, we introduce the Unit of Temperature and the method of converting each of these units to each other.

Many devices have been invented to accurately measure temperature. It all started with the establishment of a temperature scale. This scale transformed the measurement of temperature into meaningful numbers.

What is the temperature?

Temperature is a measure of the internal thermal energy state of a substance. It represents how much vibrational energy exists in the molecules of a liquid or solid, or the translational energy (speed of movement) of molecules in a gas.

Fahrenheit

The degree Fahrenheit ( o F) is the unit of temperature used by most people in the United States in describing weather.

The scale derives its name from a German-born physicist, Daniel Gabriel Fahrenheit, who is recognized as having invented it. At standard Earth-atmospheric sea-level pressure, pure water freezes at 32 o F and boils at +212 o F.

Celsius scale

The Celsius scale, previously known as the centigrade scale, is a temperature scale used by the International System of Units (SI).

As an SI derived unit, it is used by all countries except the United States, the Bahamas, Belize, the Cayman Islands, and Liberia.

It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale.

The degree Celsius (°C) can refer to a specific temperature on the Celsius scale or a unit to indicate a difference between two temperatures or uncertainty.

Before being renamed to honor Anders Celsius in 1948, the unit was called centigrade, from the Latin centum, which means 100, and grades, which means steps.

Kelvin Scale

The Kelvin Scale is a thermometric scale used in physical science to describe the absolute temperature of an object, substance, or area.

While Fahrenheit and Celsius scales measure temperature, the Kelvin Scale defines temperatures relative to an object’s thermodynamic movement.

As a result, the Kelvin Scale does not use degrees, but simply a number followed by “K” for Kelvin.

The Kelvin Scale begins at absolute zero (equivalent to -273.15° C), which is the temperature at which all objects stop moving, and ends at the triple point of water (equivalent to 0.01°C), which is the temperature at which water exists in all three states of matter simultaneously.

temperature unit conversion

 From Celsius to Fahrenheit

  • [°F] = [°C] ×9/5   + 32

From Fahrenheit to Celsius

  • [°C] = ([°F] − 32) ×5/9

From Celsius to Kelvin

  • [K] = [°C] + 273.15

From Kelvin to Celsius

  • [°C] = [K] − 273.15

From Kelvin to Fahrenheit

  • [°F] = [K] × 9/5   − 459.67

From Fahrenheit to Kelvin

  • [K] = ([°F] + 459.67) *5/9

Here you can to use temperature unit converter.

Also, you can see what you can find the store of Saba Dejlah to buy thermometer product.

You can buy the thermometer from UAE and we can send it to all of the worlds.

Temperature

Temperature

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Temperature

Temperature measurement in today’s industrial environment encompasses a wide variety of needs and applications.

To meet this wide array of needs the process controls industry has developed a large number of sensors and devices to handle this demand.

Many methods have been developed for measuring temperature.

Temperature measurement can be classified into a few general categories:

  • Thermometers
  • Probes
  • Non-contact

Thermometers are the oldest of the group.

Thermometers

A thermometer is an instrument that measures temperature. It can measure the temperature of a solid such as food, a liquid such as water, or a gas such as air.

The three most common units of measurement for temperature are Celsius, Fahrenheit, and kelvin.

Bimetal Thermometer

Bimetallic thermometers are made up of bimetallic strips formed by joining two different metals having different thermal expansion coefficients.

Basically, bimetallic strip is a mechanical element which can sense temperature and transform it into a mechanical displacement.

This mechanical action from the bimetallic strip can be used to activate a switching mechanism for getting electronic output. Also it can be attached to the pointer of a measuring instrument or a position indicator.

Various techniques such as riveting, bolting, fastening can be used to bond two layers of diverse metals in a bimetallic strip.

How ever the most commonly used method is welding. Since two metals are employed to construct a bimetallic strip, hence the name.

Probes

Following the development of the thermometer, the next step in the evolution of temperature measurement was the development of the temperature probe. In 1826 an inventor named Becquerel used the first platinum-vs-palladium thermocouple.

Prior to this time all temperature measurement was done with liquid or gas filled thermometers. The invention of the thermocouple ushered in a whole new wave of development, culminating in what we know today as practical thermometry.

This resistance element was the first in a series of devices that are not classified as probes or transducers. These fall into three general categories:

  • Resistance elements
  • Thermopiles
  • Semiconductor

Resistance elements

Resistance elements were the first probes that came into being. Early inventors understood the relationship between temperature and the resistance of different elements. This gave rise to a series of elements called thermistors.

Thermistors

The thermistor is a device that changes its electrical resistance with temperature. In particular materials with predictable values of change are most desirable. The original thermistors were made of loops of resistance wire, but the typical thermistor in use today is a sintered semiconductor material that is capable of large changes in resistance for a small change in temperature.

RTD

The Resistance Temperature Detector (RTD) technically includes thermistor devices, however the term ‘RTD’ has come to stand for the specialized pure metal detector rather than the more generic semiconductor resistance element. These pure metal devices are highly accurate and stable over long periods of time.

Here many kinds of temperature products from the best brands at the whole of the world.
All the temperature products have made from the best materials that fit with your process and varios of media.
So Saba Dejlah can help you to choose the best thermometer.

You can choose from WIKA,Ashcroft ,….and any brand that you want.