Table of contents
Demagnetisation
Demagnetisation
We have specialised in demagnetisation and offer you a variety of other devices in addition to manual versions, including electronically controlled systems .
But why do some parts need to be demagnetised, what happens during this process and why are our solutions better than those of most of our competitors? These and other questions are answered here and we take you into the fascinating world of demagnetisation.
The demagnetisation process refers to the reduction or removal of magnetism in workpieces that are held or fixed with clamping magnets. This process is important to ensure that the workpieces do not remain magnetised, which could affect their use or accuracy. Demagnetisation can be carried out in various ways, depending on the magnets used.
You can find out more about the exciting topic of demagnetisation in our technical centre.
Product overview - Demagnetising
SERIES 211-15Plate-Demagnetizing-Unit 211 / 15
Cost-effective standalone device for business and industry
SERIES 211-17Plate-Demagnetizing-Unit 211 / 17Robust version with greater effective depth and maximum tightness
SERIES 211-28Plate-Demagnetizing-Unit 211 / 28Extremely low overall height with maximum effective depth
SERIES 211-40Plate-Demagnetizing-Unit 211 / 40The solution for all applications
SERIES 215Plate-Demagnetizing-Unit 215Particularly strong demagnetising effectSERIES 215RPlate-Demagnetizing-Unit 215 RVersion with roller conveyorSERIES 215PPlate-Demagnetizing-Unit 215 PPortal versionWhat happens during demagnetisation?
The physical process of demagnetisation:
Tiny magnetic fields, so-called molecular magnets, are present in magnetisable (ferromagnetic) materials. Without the influence of an external magnetic field, these molecular magnets are arranged completely randomly. When an external magnetic field is applied, the molecular magnets begin to align themselves. The stronger the external magnetic field, the more the molecular magnets are aligned until they reach magnetic saturation. Once the external magnetic field is removed, this forced formation remains in place.
The parts are demagnetised by passing them through a strong alternating magnetic field , which gradually decays. The molecular magnets are constantly remagnetised by the alternating field. If the magnetic field strength is now continuously reduced, fewer and fewer of the elementary magnets are aligned.
The reduction of the magnetic field strength is achieved by slowly and evenly moving the part out of the alternating field.
The reduction of the magnetic field strength is achieved by slowly and evenly moving the part out of the alternating field.
What does the degree of demagnetisation depend on?
The demagnetisation process depends on:
- the size, shape and material of the parts to be demagnetised
- the distance between the parts and the demagnetiser
- the distance between the parts
- the magnetic state before demagnetisation and the permissible limit values after demagnetisation
- the speed at which the workpiece is moved through the demagnetisation area
- the frequency of the alternating magnetic field
Why demagnetise
Many machined parts must not have any residual magnetism due to their intended use.
If materials or tools are magnetised, this leads to undesirable effects, such as
- adhering steel chips or grinding dust
- Assembly problems
- blowing effects that make welding more difficult or lead to faulty weld seams
- Sticking parts in collection containers or on machine parts
- premature wear of components due to adhering microparticles, e.g. in bearings and gears
The magnetisation of materials can be achieved by
- transport with lifting magnets or magnetic roller conveyors
- Magnetic particle testing
- Magnetic clamping devices
- DC welding with high currents
- Induction hardening