7 Uses for an Induction Heating Machine + How to Make One

In this video I show you how to cryogenically case harden your low carbon steel parts with the induction heater. What you end up with is a material that has a ductile inner core with a hard outer shell. Parts that require impact resistance as well as abrasion resistance are great candidates for case hardening. Low carbon steel does not harden well on its own. When heating the part up and submerging it in a carbon compound, carbon gets impregnated into the surface of the material. This results in a hard outer surface.

Goto Duolin to know more.

Gears, Firing pins, Engine Camshafts, Lock Shackles, Security Fasteners, and Self Drilling Screws are all commonly case hardened. The method of case hardening used in the video is also known as carburizing with a cryogenic treatment. Liquid nitrogen is usually used but I used a isopropyl alcohol dry ice bath. Liquid nitrogen would provide even more benefits by converting even more retained austenite to martensite. Also, if you don't mind the darkness of the part after the hardening process, it's best not to polish it for even more rust protection. The method used in the video can be repeated multiple times until the desired hardness is achieved.

Induction is particularly good at case hardening. This is because of the skin effect discussed in the next step. The same high frequency skin depth that is seen in the working coil is also seen in the part being heated. The higher the frequency, the more the current is flowing on the outside of the material. For steel in this case, the current is only flowing about 6 thousandths of an inch deep. This is perfect for case hardening.

This process should only be used with low carbon steel so I'll show you a way to determine what type of steel you have.

In this video, I'll show you an easy way to determine the carbon content of your steel parts by observing the spark profiles. You can use this technique to find which of your parts would benefit from the case hardening method used in my last video. This is not the most accurate way of determining the composition of the steel, but many welders use this technique when welding unknown materials and is a good test for most non-critical jobs. This technique is known as spark testing.

In this video, I make a pancake coil attachment and boil water in about 10 seconds. It works by pulsing the DC at a high frequency(about 160kHz). This creates a constantly changing magnetic field that induces eddy currents in the cast iron skillet. Induction heating is more efficient than many other methods because there is less wasted heat. For example, induction cooktops are more efficient than electric and gas stoves.

The use of my wire choice is quite important here. I used what is known as Litz wire. Litz wire consists of many individually insulated wires. It is the preferred wire for use in high frequency application due to the skin effect.

The skin effect is the tendency of current to flow on the outside of a conductor at high frequencies. The higher the frequency, the shallower the skin depth will be. Using Litz wire will result in much more efficient working coils for your system. Not only does it transfer the energy more efficiently, it also generates less heat of its own. If you have 10amps flowing through 260 strand Litz wire, that's only 38mA of current in each wire. 10amps through a single conductor will generate substantial heat depending on the size.

The company is the world’s best Custom Induction Heating Equipment supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

If you do not want to use Litz wire, the next best thing is copper tubing. It has more surface area for the current to flow so it is more efficient than an equivalently sized solid core wire.

This induction heater works by pulsing the DC at a high frequency(about 160kHz). This creates a constantly changing magnetic field that induces eddy currents in conductive materials near the coil. Ferromagnetic materials will also heat up due to hysteresis. This is the heat produced from rapidly changing magnetic fields in the material. Induction heating is more efficient than many other methods because there is less wasted heat. For example, induction cooktops are more efficient than electric and gas stoves. I'll be making more attachments and demonstrating more practical uses for inductive heat.

It's a common misconception that induction heaters don't work for aluminum and other non-ferrous metals. This is not true. This induction heater will heat up aluminum and copper just fine, but not as fast as ferrous metals. This is mainly due to their lower resistivity. The higher the resistivity of the conductive material, the more it generates heat when current is passed through it. The higher resistivity of most ferrous metals coupled with the heating due to hysteresis makes them ideal for induction heating, but they are not the only metals affected by induction.

The three main components of the machine are the power supply, the ZVS driver, and the working coil. The ZVS driver,(Zero Voltage Switching) was invented by Vladmiro Mazilli. It uses resonant zero voltage switching (also know as ZVS) to pulse the power supply very rapidly. This means the MOSFET's are designed to switch (on or off) when the voltage across them becomes zero. Since the MOSFET's switch when there is no voltage across them, they generate very little heat. The main source of heat is caused by the MOSFET's internal resistance and the capacitors constantly charging and discharging. The circuit is fairly simple consists of just two MOSFETs, 6 capacitors, and a few resistors and diodes. You can build the circuit yourself, but it is cheaper to buy a premade board.

The induction heating coil (or inductor) is a very important part of every induction heating system.  An induction heating coil is so much more than meets the eye.  This coil is not just a piece of copper pipe, but a tuned solution to optimize your equipment performance and save on energy used. The coil transfers high-frequency electromagnetic energy from the induction system’s output into the work piece (load).

A typical coil consists of:

• Coil leads (or bus bars)
• Terminals – to connect to the induction system output
• Coil turns – windings of the copper pipe or wire

Coil electrical parameters – coil inductance, resistance, and number of turns all play a very important role for the optimal performance of the coil. The coil must be designed so these parameters match well with the output parameters of the induction power supply. This way the energy can be efficiently transferred from the power source into the heated work piece.

Cooling requirements – The coil is usually made from a copper tube, but can be also made from any conductive material or dry cable. Usually water cooling is required to dissipate the energy lost in the coil. For this reason, the water cooling requirements need to be carefully calculated – water flow, water pressure, cooling liquid type, etc.

For more Induction Forging Machineinformation, please contact us. We will provide professional answers.