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Thermocouples are among the most commonly used types of temperature sensors worldwide. They're widely popular in various fields due to their affordability, durability, and versatility. The applications of thermocouples range from ceramic, gas, oil, metal, glass, and plastic to food and beverage.

You can use them anywhere to monitor or record data regarding temperature accurately. Thermocouples are well-known for generating temperature measurements with fast response and excellent resistance to shock, vibration, and high temperatures.

The common industrial applications for thermocouples are discussed in detail below.

A thermocouple is a sensor tool used to measure temperature in scientific, manufacturing, and machining applications. It's constructed by joining two different metal wires, forming a junction. This junction produces a predictable voltage above a given temperature range. A thermocouple usually utilises a Seebeck or thermoelectric effect to change the voltage to a temperature measurement.

What are the common industrial applications for thermocouples?

Here is an overview of common industrial applications for thermocouples.

1. Thermocouples for the food and beverage industry

There are multiple applications for thermocouples in the food and beverage industry, such as pasteurisation, refrigeration, fermentation, brewing, and bottling. You don't have to worry when using a thermocouple temperature sensor because it offers accurate temperature readings for frying and cooking to ensure your food is well-cooked.

Restaurant appliances like grills, toasters, fryers, warmers, and ovens often use thermocouples. Also, you're likely to find thermocouples in the form of temperature-sensing probes in cooking equipment used in large-scale food processing operations.

Thermocouples are also used in breweries because beer production requires precise temperatures for proper fermentation and prevention of microbial contamination.

Coming up with an accurate temperature measurement for molten metals like steel, zinc, and aluminum can be challenging because of the extremely high temperatures involved. The temperature sensors widely used for molten metals are Types B, S, and R platinum thermocouples and Type K and N base metal thermocouples. Choosing the ideal type would depend on the temperature range of your specific metal-related application.

Base metal thermocouples normally use #8 or #14 American wire gauge (AWG) with metal protection tubes and ceramic insulators. On the other hand, platinum thermocouples often use diametres ranging from #20 to #30 AWG.

3. Thermocouples for the plastic industry

Manufacturing plastic products needs precise temperature control. Thermocouples are usually required in various areas for temperature monitoring during plastic processing. They're used to measure the melting or surface temperature in diecasting molds and injection.

Before you use thermocouples in plastic processing, you must know that thermocouples in the plastic industry are categorised into two. The first category involves measurement. Here, you can use the thermocouple to determine the transfer of plastic heat function depending on their cross-section. Remember, the thermocouple must determine the applied force dissimilarity, primarily for its velocity and orientation.

You can also use thermocouples when designing products in plastic industries. Thus, the second category of thermocouple application in the plastic industry involves product design and engineering. In product engineering, you must use the thermocouple in calculating materials' temperature changes, especially during the product's shelf life.

Engineers may select a thermocouple suitable for the materials they want to use in manufacturing their products. Similarly, they can utilise the thermocouple to examine the design performance. This will allow them to make changes before starting the production process.

The furnace conditions will largely determine the appropriate thermocouple for high-temperature laboratory furnaces. Therefore, to choose the best thermocouple, you need to consider a few factors, such as:

In most cases, extruders require high pressure and temperatures. Thermocouples for extruders are designed with a threaded adapter, which helps you position its sensor tip in molten plastic, usually under high pressure.

You can get these thermocouples either in single or dual elements, incorporating a distinct threaded housing. Bayonet thermocouples (BT) and compression fitting (CF) thermocouples are commonly used on the parts of an extruder with low pressure.

There are different types of thermocouples with multiple applications in various industries. Thus, whether you're engaged in engineering services, steel fabrication, food and beverage, or plastics processing industries, you may find that thermocouples are widely used to measure and monitor temperature.