Skip to content Skip to main navigation Skip to search
Preheating with induction heating

Induction preheating

Induction preheating is a process where materials or workpieces are heated by induction prior to further processing.
Close

What is induction preheating?

Induction preheating is a process where materials or workpieces are heated by induction prior to further processing. The reasons for preheating vary. In the cable and wire industry, cable cores are preheated before insulation extrusion. Steels strips are preheated prior to pickling and zinc coating. Induction preheating also softens metals before bending, and prepares tubes and pipes for welding. Mobile preheating solutions facilitate onsite repairs of bearing assemblies.


What are the benefits?

EFD Induction preheating systems are extremely efficient, resulting in major energy savings. When preheating steel strips and cable and wire, diode rectifiers ensure a constant power factor of 0.95, thus eliminating reactive power costs. Cycle times are short, and continuous automatic matching means a single coil can handle wide production ranges. Induction preheating systems are compact and easy to integrate into existing or planned production lines.


Where is it used?

Induction preheating is employed in the automotive, mechanical, aeronautical, electrotechnical, white goods and shipbuilding industries. A major area of use is preheating for welding. Our mobile Minac systems are used in the offshore sector for onsite weld preheating. Minac units are also frequently flown to oil platforms and airports to perform repairs and maintenance.

 

Images

Preheating with induction heating

An operator replaces a bearing that has been heated with an EFD Induction mobile Minac system.

Preheating with induction heating

EFD Induction systems have been used for hot tap welding on the bed of the North Sea. Photo :Technip Norge AS

Preheating with induction heating

Hot tap welding. Most of the equipment needed for the preheating was housed in this skid and a container on the ship’s deck. Only the coils and the thermocouples were brought into the subsea habitat. Photo :Technip Norge AS

Preheating with induction heating

Specialist coils being tested for the Tampen subsea hot tapping project. See pp. 12-14 for more details about this technically advanced use of induction heating in the offshore industry. Photo :Technip Norge AS

Preheating with induction heating

A medium-frequency EFD Induction Sinac pre-heats seamless offshore pipe prior to coating.

Preheating with induction heating

No dust, no fumes, no noise. An EFD Induction heater gets to grip with 170mm anode stubs.

Bolt expansion with induction heating

Induction heating is increasingly used to remove the giant nuts and bolts in power stations' turbines.

Induction heating of wire and cable

EFD Induction designs and builds specialized systems for steel strip and wire and cable pre-heating.

Induction heating in the oil and gas industry

Minac units are frequenctly flown to oil platforms to perform repairs and maintenance.

Preheating with induction heating

Welding the branch pipe onto the live, pressurized main pipe. The induction coil is wrapped in white insulating material. Photo :Technip Norge AS

Preheating with induction heating

The ‘Safe Concordia’ accommodation and support platform. A mobile EFD Induction Minac system was used to pre-heat the weld area during the welding of a patch onto a crane tower.

Induction heating equipment

An example of induction pre-heating: the pipe is being heated prior to receiving an anti-corrosive coating.

An induction coil specially designed and built for offshore industry requirements. Once heated by the coil (in red), the pipe can receive an anti-corrosion covering.

News