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Adjustable Shock Absorber
An oil filled shock absorber is incorporated on the backside of the magnet in order to absorb any recoil energy of the
lever. The thinner the material to be lifted the higher the recoil energy to be absorbed. The set screw on the backside
of the magnet makes it possible to adjust the shock absorber variably, so that the upward movement of the lever is
controlled and operates smoothly. This adjustment should be made by using a flat-blade screwdriver.
Basic Information on the Load-bearing Capacity of the Lifting Magnet
The magnetic surface is located on the underside of the lifting magnet incorporating multiple magnetic poles which
generate the magnetic holding force when activated. The maximum holding force that can be achieved depends on
different factors which are explained below:
Material thickness
The magnetic flux of the lifting magnet requires a minimum material thickness to flow completely into the load. Below
this minimum thickness of material, the maximum holding force is reduced subject to material thickness. Conventional
switchable permanent magnets have a deep penetrating magnetic field similar to tree tap roots, and require a large
material thickness to achieve maximum holding force. The compact magnetic field of the TML magnets is similar to
a shallow root and achieves maximum holding force even when used on thin materials (see table 2, chapter "Detailed
Performace Data").
Material
Every material reacts in a different way to penetration of the magnetic field lines. The load-bearing capacity of the
lifting magnets is determined using a low carbon material. Steels with high carbon content or whose structure has
been changed by heat treatment have a lower holding force. Foamed or porous cast components also have a lower
holding force, so that the given load-bearing capacity of the lifting magnet can be downgraded on the basis of the
following table1.
Table 1
Material
Non-alloyed steel (0.1-0.3% C content)
Non-alloyed steel (0.3-0.5% C content)
Cast steel
Grey castiron
Nickel
Most stainless steels, aluminium, brass
Surface quality
The maximum holding force of a lifting magnet can be achieved in case of a closed magnetic circuit in which the
magnetic field lines can connect up freely between the poles, thus creating a high magnetic flux. In contrast to iron,
for example, air has very high resistance to magnetic flux. If a kind of "air gap" is formed between the lifting magnet
and the work piece, the holding force will be reduced. In the same way, paint, rust, scale, surface coatings, grease
or similar substances all constitute a space, or an air gap, between work piece and lifting magnet. An increase in
surface roughness or unevenness also has an adverse effect on the magnetic holding force. Reference values can
be found in the performance table of your lifting magnet.
Magnetic force in %
100
90-95
90
45
11
0
15
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