Industrial heating – furnace and kiln features

Industrial furnaces, kilns, ovens, and dryers play a significant role in different processes to modify the properties of parts and materials by applying controlled heat.

With higher capacity and power than their domestic counterparts, these systems can handle large production volumes and reach higher temperatures.

This article will delve into the main characteristics that distinguish them. We will also touch on the differences between furnaces and kilns, as well as low-temperature ovens and dryers.

In addition, we will explain this equipment's most common classification categories according to process, heat source, and temperature range.

Fig. 1 Elevator Kiln for Ceramics

Industrial Furnaces and Kilns – Definition and Characteristics

Industrial furnaces and kilns are pieces of equipment designed to heat, dry, melt, and harden, among other processes, on an industrial scale.

They are used in various industries such as metallurgical, foundry, ceramics, automotive, aerospace, construction, refractories, and electronics, among many others.

To choose the most suitable furnace or kiln, consider the following beforehand:

• Heating process. Which involves knowing the type of heat treatment required according to the industry.
  
• Temperature range. Because depending on the material, the application, and the process temperature, the type of furnace or kiln may vary. Knowing the required minimum or maximum ranges is essential as one of the first selection criteria.
  
• Heat source. Furnaces and kilns can work with natural or LP Gas, electricity, or other fuel types, each with advantages and disadvantages.
  
• Control systems: Having control over temperature and other variables for consistency throughout the process is necessary.
  
• Size of the equipment. Dimensions must be considered since it is necessary to know beforehand the amount of material to be processed per load, in order that the most efficient design is achieved.
  
• Energy efficiency. This will save on operating costs and reduce environmental impact.
  
• Safety in line with standards. Finally, this set of regulations intends to minimize risks near or around industrial furnaces and kilns. An example is the NFPA 86 standard, among others.

At NUTEC Bickley, we have a wide variety of furnaces and kilns customized according to the needs of users. In addition, we offer the service of project development with engineering for our clients. Request a quote from our advisors today.

Differences Between Furnaces, Kilns, Ovens, and Dryers

Each has unique characteristics that differentiate them. For example:

• Furnaces. They are designed to heat treat ferrous and non-ferrous metals.
• Kilns. They are designed for ceramic products, glass, and other materials.
  
  

Both furnaces and kilns handle temperature processes above 930°F (500°C).

Ovens & Dryers work for both metallurgy and ceramics. However, they can only handle lower temperatures, below 930°F (500°C), and are used during heat treatment and drying.

Fig. 2 Low temperature ovens and dryers

Types of Industrial Furnaces and Kilns

Although there are a variety of classification categories for industrial furnaces and kilns, we will focus on the most commonly used ones.

According to Thermal Process

From ceramic firing to metal heat treatment, one of the most important factors to consider when choosing a furnace or a kiln is the thermal process to be carried out.

Some of the most common thermal processes in furnaces are:

• Heat treatment: aims to improve the hardness, strength, and other properties of materials, from ferrous (steel, alloy steels, iron) to non-ferrous (aluminum, titanium, copper, zinc) metals.
• Foundry: furnaces can melt metals, glass, and other materials for further processing.
  
  

The most common thermal processes in kilns are:

• Ceramic firing. This process involves heating the material at a high temperature until it vitrifies (hardening) and becomes durable.
• Glass melting: Glass is heated and held to a specific temperature until reaching its melting point.
  
  

The thermal processes that are usually carried out in Ovens and Dryers are:

• Curing and drying. For composite materials and polymers manufacturing. Low temperature ovens and dryers can provide the proper temperature and humidity for these processes.

Discover the variety of furnaces, kilns, ovens, and dryers that we offer at NUTEC Bickley.

According to Temperature Range

Another important factor to consider when choosing a furnace, kiln, oven, or dryer is the required temperature range. This variable will determine the insulation capacity and the type of energy source to carry out specific processes.

Two subcategories within this main one are "high" and "low" temperatures.

• High Temperature Furnaces and Kilns. Designed to operate above 1830°F (1000°C). They are mainly used for forging and heat treatment.
  
  We can mention forging and foundry among the industries that usually use this furnace or kiln type.
  
• Low Temperature Ovens and Dryers. Designed to operate typically below 1200°F (650°C). They are mainly used for heat treatment, curing, and drying processes.
  
  We find foundry, steel, aluminum, refractories, sanitaryware, abrasives, and technical ceramics within the industries that most benefit from this equipment.
  
  

Fig 3. Forging Car Bottom Furnace

Furnace and Kiln Types According to Application

In addition to the previously mentioned categories, we list the most common types of furnaces and kilns depending on their industry and application.

1. Box Furnace. This equipment has a system of one or multiple doors, which can be vertically operated or be of the swing type.
2. Tunnel Kiln. The product is transferred inside a hot tunnel, and the kiln’s temperature varies across its different sections.
3. Shuttle Kiln. Batch firing in the ceramic industry. That is, it allows the loading and unloading of material when cold or when the heating process has yet to start.
4. Car Bottom Furnace. Typically for processes involving the handling of large and heavy, unusual parts, or multiple configuration loads.
5. Bell Furnace. The load is heated inside a mobile cover or dome, which can be removed using a traveling hoist.
6. Continuous Furnace with Conveyor. Either with rollers, mesh belts, walking beams, pushers, etc., within.

Conclusion

Furnaces, kilns, and ovens are crucial in different industrial heating processes. Each industry has particular needs, so considering factors such as the type of material and its handling, the required temperature, and the process to be executed, is necessary when choosing the right one.

Companies must consider all of the above to achieve consistent, high quality results while minimizing costs and any environmental impact.

About NUTEC Bickley

At NUTEC Bickley, we have more than 45 years of experience designing and manufacturing highly specialized kilns for ceramics, industrial furnaces for metals, plus combustion systems and thermal insulation solutions.

We have a presence in more than 50 countries and have worked with clients from various sectors, including automotive, aerospace, food, ceramics, metallurgical, and many more industries.

Are you interested in learning about the equipment and heat treatment systems we handle at NUTEC Bickley? Contact us for personalized advice.


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