What Is Induction Heating?

What is induction heating is and what can it do?

Induction heating is a method for heating metals or other electrically conductive materials with an electromagnetic field to ‘induce’ a current in that material. This current results in friction, heating the material.

What goes into an induction heating system?

Operating Frequency

The size of the work piece and the heating application dictate the operating frequency of the induction heating equipment. Generally, the larger the work piece the lower the frequency, and the smaller the work piece the higher the frequency. The operating frequency is determined by the capacitance of the tank circuit, the inductance of the induction coil and the material properties of the work piece.

 

Magnetic Materials & Depth of Penetration

If your work piece material is magnetic, such as carbon steel, it will be heated easily by induction’s two heating methods, eddy current and hysteretic heating. Hysteretic heating is very efficient up to the Curie temperature (for steel 600°C (1100°F)) when the magnetic permeability reduces to 1 and the eddy current is left to do the heating. Induced current in the work piece will flow at the surface where 80% of the heat produced in the part is generated in the outer layer (skin effect). Higher operating frequencies have a shallow skin depth, while lower operating frequencies have a thicker skin depth and greater depth of penetration.

Coupling Efficiency

The relationship of the current flow in the work piece and the distance between the work piece and the induction coil is key; the closer the coil, the more current in the work piece. But the distance between the coil and the work piece must first be optimized for the heating required and for practical work piece handling. Many factors in the induction system can be adjusted to match to the induction coil and optimize the coupling efficiency.

Importance of Coil Design

Induction heating efficiency is maximized if your work piece can be placed inside the induction coil. If your process won’t allow your work piece to be placed inside the coil, the coil can be placed inside the work piece. The size and shape of the water-cooled copper induction coil will follow the shape of your work piece and be designed to apply the heat to the correct place on the work piece.

Coil design blog posts

Power Requirements

The power required for an induction machine (or induction oven) to heat your work piece depends on:

• The mass of your work piece
• The material properties of your work piece
• The temperature increase you require
• The heating time required to meet your process needs
• The effectiveness of the field owing to the induction coil design
• Any heat losses during the heating process

After we determine the power needed to heat your work piece we can select the best induction heater taking the induction coil coupling efficiency into consideration.

Can induction heating improve your process heating?

If your process is a good fit, induction can improve your process efficiency, throughput and safety. But not every application is appropriate for induction. Consideration of any heating process that does not take advantages of induction heating’s primary benefits of precision and repeatability should be discouraged. For example, some materials don’t respond well to rapid heating. Brazing two materials with very different thicknesses or metallurgical properties can have sub-optimal results. Heating water can be accomplished much more efficiently and economically with resistance or flame.

Solution

To begin, there are many videos on YouTube and on our website that demonstrate induction heating’s capabilities. You can get an idea from these if the technology is a good fit for your process. To fully answer this question, an evaluation of your materials, process and production requirements should be done to see if induction heating can benefit your process.

Consideration of any heating process that does not take advantages of induction heating’s primary benefits of precision and repeatability should be discouraged. For example, some materials don’t respond well to rapid heating. Brazing two materials with very different thicknesses or metallurgical properties can have sub-optimal results. Heating water can be accomplished much more efficiently and economically with resistance or flame.

How Ambrell can help you determine if induction is a good fit for your process

Yes. In order to deliver the right solution for the right process, we offer free lab service where we design and test the optimal induction heating solution for your application. Send us your parts and process requirements. Our engineers will analyze your process and heat your parts to develop the right solution for your specific application. You will receive your parts back for inspection as well as a video of the heating process of your parts, and a laboratory report with a system recommendation.

Does your heating process cost too much and waste too much energy?

Heat losses and uneven, inconsistent application of heat result in increased scrap and diminished product quality, driving up per-unit costs and consuming profits. Best economies are seen when the application of energy is controlled.

To bring a batch oven up to temperature and to hold the entire chamber at the required temperature for the process time demands much more energy than is required to process the parts. Flame-driven processes are inherently inefficient, losing heat to the surroundings. Electrical resistance heating can also result in the wasteful heating of surrounding materials. Applying only the energy needed to process your parts is ideal.

The precision and repeatability that are inherent to induction heating help you to reduce your process scrap rate and to improve throughput. The selective application of heat to the targeted area of your part enables very tight control of the heating process, cuts the heating time and limits energy requirements.

Solution

For a new system, induction heating can be a much more efficient and economical heating process than a batch-type approach. The precision and repeatability of a well-designed induction process are unmatched.

For an existing batch process, induction can improve throughput if deployed in a pre-heat stage. Flame-driven processes are inherently inefficient, losing heat to the surroundings and to human variability.

Induction selectively focuses energy only on the area of the part that you want to heat. Each part in your process enjoys the same efficient application of energy. Since the energy is transferred directly from the coil to your part, there is no intervening media like flame or air to skew your process. The process is repeatable by design.

Can Ambrell help you control the costs of your process?

Probably. In order to deliver the right solution for the right process, we offer free lab service where we design and test the optimal induction heating solution for your application. Send us your parts and process requirements. Our engineers will analyze your process and heat your parts to develop an economical solution for your application. You will receive your parts back for inspection as well as a video of the heating process of your parts, and a laboratory report with a system recommendation.

Can you improve your heating process efficiency and produce more in less time?

Delivering the highest quality parts for the least expense in the least time is accomplished with an efficient process, in which the input elements of materials and energy are tightly and precisely controlled. Targeted application of heat to the part or an area of the part provides the most uniform results for the least cost.

Batch heating in an oven requires an investment in time and energy that serves only the process, not the product. Throughput and efficiency are increased by the careful application of energy (heat) in amounts no more than required by the product.

Solution

Repeatability and throughput are two things that can be greatly improved with induction compared to resistance or flame heating. Induction delivers savings primarily from significant reductions in process scrap rates, improved throughput and from the thrifty use of energy. There is no need for process ramp-up; heat is applied and stopped instantly.

Can Ambrell help you improve the efficiency of your process?

Our applications lab will recommend the optimal induction heating solution for your application, based on the parts, needs and information you provide. The selective application of induction heat and the instant-on/instant-off nature of the technology work together to boost your process efficiency. You can learn more in our blog post 'Advantages of Induction Heating: Increased Production Efficiency'.

Want more consistent results in your heating process?

Hot-spots or cold-spots in your process depress the quality of your work. Inconsistent heat application by hand or by poor control of applied energy adds variance to your process. Monitoring and controlling material, time and energy inputs to your process drives quality.

Solution

Repeatability and throughput are two things that can be greatly improved with induction compared to resistance or flame heating.

Do Ambrell's heating systems deliver consistent heating results?

The precision and repeatability that are inherent to our heating technology help you to reduce your process scrap rate and to improve throughput. The selective application of heat to the targeted area of your part enables very tight control of the heating process, cuts the heating time and limits energy requirements.

Induction selectively focuses energy only on the area of the part that you want to heat. Each part in your process enjoys the same efficient application of energy. Since the energy is transferred directly from the coil to your part, there is no intervening media like flame or air to skew your process. The process is repeatable by design.

Want to reduce the energy use in your heating process?

Delivering the highest quality parts for the least expense in the least time is goal of an efficient process, in which the input elements of materials and energy are tightly and precisely controlled. Targeted application of heat to the part or an area of the part provides the most uniform results for the least cost.

Solution

The precision and repeatability that’s inherent to induction heating help you to reduce your process scrap rate and to improve throughput. The selective application of heat to the targeted area of your part enables very tight control of the heating process, cuts the heating time and limits energy requirements.

How can induction heating help you control your energy costs?

For a new system, induction heating can be a much more efficient and economical heating process than a batch-type approach. The precision and repeatability of a well-designed induction process are unmatched. For an existing batch process, induction can improve throughput if deployed in a pre-heat stage. Flame-driven processes are inherently inefficient, losing heat to the surroundings and to human variability.

Savings that induction delivers arise primarily from significant reductions in process scrap rates, improved throughput and from the thrifty use of energy. There is no need for process ramp-up; heat is applied and stopped instantly.

Want to make your heating process safer?

Any heating process carries a risk of operator contact with the heated materials.

Solution

A technology that limits the extent of operator-contacted surfaces reduces the overall risk. If heating can be limited to only the part and further limited to a zone of the part, safety is improved even more.

Are our induction systems safe?

Once established and proven, an induction heating process does not require highly-trained personnel to operate. Compared to a flame or hand-held heating operation, each induction heat process cycle is identical, and the process requires no running adjustment.

Where else is induction heating being used?

Industries

We have a collection of materials that showcase industries that make effective and economical use of this technology. See how companies like yours benefit from induction heating.

Processes

Induction is used very effectively in many processes like brazing, soldering, shrink fitting. Anywhere metal is heated, induction can be used. From something as small as a hypodermic needle to a large wheel on a tank. Many companies in the automotive industry, medical industry as well as aeronautics make efficient use of induction heating in their processes.

Why are different induction heating models used for different processes?

Models differ by power and frequency outputs. These have been designed for different sized parts as well as for different heating patterns and requirements. Models with lower the frequency outputs deliver heating deeper into the the part. Models outputting higher frequencies concentrate heat closer to the surface of the part.

Can Ambrell help you set up and maintain an induction heating system?

Most definitely! With any EKOHEAT system, we highly recommend that you purchase a Start-Up assistance. One of our highly-trained staff will come to your facility, teach your operators how to run the machine, and ensure that the process runs as promised. We will also train your maintenance personnel on how it works and how to troubleshoot it if you wish.

Our SmartCARE service department proudly provides the most responsive and supportive program in the industry. We dispatch our team wherever and whenever our customers need our help.

We can help

We are dedicated to the whole customer experience. Our mission begins in THE LAB, where we solve our customers’ most challenging heating applications, identifying processes that can benefit from our remarkably reliable systems. Our SmartCARE service personnel are trained to get and keep our customers up-and-running.