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Why implementing sensors is important?
Understanding the importance of implementing sensors in surface conditioning industry is one way to
enhance digitalization in this industry. What kind of sensors are the most valuable?

Thinking of surface conditioning, we usually talk about heating and cooling treatment of metallic parts.
Indeed, temperature sensors are probably the most valuable sensor in this industry. It monitors
heating and cooling circuit variations, checks at any time the inside temperature of the furnace. In
addition, it can reduce energy consumption by monitoring temperature variations.

Another useful sensor is the pressure sensor. Indeed, this sensor can help identify any leakage or
breakage into the furnace. Consequently, it turns into energy and money savings for industries. For
example, during vacuum carburization, monitoring pressure allows operators to determine the
amount of gas injected and thus, the amount of carbon diffused into the metal depending on the
duration of carburization.

Which type of sensors must be used?
Many actual sensors operate as hardware sensors. The principle of these sensors is based on the
measurements of environmental properties such as position, acceleration, temperature, or pressure.
Thermometers and barometers belong to this category of sensors. This type of sensor is the most
common used in industries.

Other sensors are developed, and the benefits provided for industries are greater than hardware
sensors. These sensors are called soft sensors or virtual sensors. Like hardware sensors, soft sensors
create signals which transmit measurements data. However, the signal is produced by a software
which can proceed a significant number of measurements at the same time. As soft sensors provide a
lot of data, they can also be used to calculate quantities that are not measured using data of hardware
sensors installed. This type of sensor is of real interest when a significant number of measurements of
different characteristics are analysed. Consequently, it can easily prevent possible machines failures
and thus, generate savings for companies.

Fig. 6. 21 Process of soft sensor technology

Fig. 6. 21 describes the process of soft sensor technology. Based on hardware sensors measurements
and application of numerical models using filtering techniques, soft sensors provide estimates of
quantities not measurable with hardware sensors.

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