Standard_Parts_Catalogue

Page 2029 | 3.9 Holding with Magnets 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Magnetic force In addition to their shape and material, the actual achievable magnetic force of the magnets depends on other factors. Retaining Magnets / Raw Magnets Magnetic Force / Influence Factors The nominal magnetic forces stated in the tables in the standards are minimum values, which are achieved at room tem- perature, vertical „pull-off“ and full contact of the magnets with low carbon steel workpieces and a minimum thickness of 10 mm. Influence factors Air gap An air gap or materials, which are not magnetically per- meable between the workpiece and the magnet, have an insulating effect on the magnetic flux. The magnetic force is reduced depending on the distance. Workpiece thickness A minimum thickness of the workpiece should be main- tained in order to not restrict the magnetic flux and therefore the magnetic force. Material Steel and ferrous materials with a low proportion of carbon and alloyed materials promote the magnetic flux. Similarly, non-hardened workpieces conduct the magnetic flux better, which enables greater magnetic forces. 100% technical pure iron  86% C60, X6Cr17  95% St37, C15  84% 42CrMo4  94% St44-2, 34CrNiMo6  75% St50  93% St52-3  72% X155CrMo12  92% 90MnV8  65% X210CrW12  90% C45  50% 20MnCr5  87% Ck45  30% GG Workpiece surface Excessive roughness or unevenness have the same effect as an air gap. They reduce the magnetic force. Displacement force The displacement force corresponds to the frictional force and depends on the coefficient of friction bet- ween the magnet and the workpiece, as well as the magnetic force of the magnet. Due to their higher coefficient of friction, rubberized magnet systems have greater displacement forces.