High-power magnets in practical use
Increasing demands for the cleanliness of food products, raw materials and operating equipment, as well as a desire for machines to have a longer service life, are motivating more and more producers to improve their manufacturing processes. In particular the amount of the finest foreign iron particles (from abrasion, introduced by raw materials, etc.) in many areas is still underestimated.<br/> <br/> One cost-effective way of counteracting this problem is to use high-power permanent magnets. When selecting the devices, the customer’s requirements and operating conditions are taken into account.<br/> <br/> The high-power magnets used and the method of construction ensure that particularly high surface flux densities of up to 1.4 Tesla (14,000 Gauss) are achieved, and foreign iron particles of 5 µm and larger are separated out of liquid products and of 25 µm and larger out of powder products.<br/> <br/> The surface flux density is not to be confused with the residual magnetism of the magnetic material used, known as the Br value, but represents the actual measurable size on the surface of the magnetic rod.
The careful choice of materials guarantees the durability of the magnets. No decrease in the surface flux density (demagnetisation) is possible under the specified operating conditions.
In contrast to the standard metal detectors available on the market, only foreign iron particles are removed from the product flow with these high-power magnets, saving the usual extraction. Practical experience has shown that approximately 80-90% of foreign particles are magnetisable, hence they can be removed from the product flow with magnetic filters.<br/> <br/> The use of high-power magnets allows ATEX requirements to be fulfilled in explosion-protected plant areas by minimising particles that trigger sparks.