Tuesday 27 May 2014

Evolution Of Overband Magnetic Separators

The basic concept of magnetic separators lies in their use of magnetic properties of one material to separate ferrous impurities from other materials. The concept was first innovated by Orange F. Merwin, who used a plain magnetic plate for separation of ferrous impurities. This was particularly popular amongst farmers in the 1940s, as it proved very useful for eliminating metallic impurities from grains.

Magnetic separators work on the basic principle of varying magnetic properties of different constituents. The way a ferrous material reacts to the magnetic field around it, is different from the way plastic, wood, or glass would react to the same. This simple, yet useful, functionality of magnetic separators led to a good amount of research and development of their functionalists. In addition, this has made them an essential component of many large, as well as small-scale, industries.

Magnetic separators can also be used to sort various types of metals, by employing a series of separators, varying in intensity, to pull out strong and weak magnetic materials, at different times. There are different types of magnetic separators available in the market, such as:
  • Permanent magnetic separators
  • Overband magnetic separators
  • Single and double drum type magnetic separators
  • Magnetic ferrous traps
  • Plate and hump magnetic separators
  • Magnetic coolant filters
  • Magnetic pulleys and grids
  • Suspension magnetic separators

Overband magnetic separators, also known as cross-belt magnetic separators, are one of the most useful and common types of magnetic separators, used in various industries, related to cement, food, fertilizers, chemicals, plastics, coal handling, thermal power etc. They are also employed in various recycling plants to separate metal scrap from the clutter, in the most efficient manner.

Cross belt magnetic separators are easy to use, and can be suspended conveniently, either parallel or perpendicular to the material flow over the conveyor belts and feeders, through eye bolts. These magnetic separators automatically discard the tramp iron from the rest of the material, being carried over conveyor belts, vibratory feeders or inclined planes, and discharge it to a collection bin by the cleated belts.

Cross type magnetic separators are available with both permanent magnets and electromagnets, depending on their applications and requirements of the user. While electromagnetic separators use more power to operate, compared to permanent magnet separators, they also provide the advantage of the operation being turned off at any instance, when it becomes dangerous to keep the separator running. Besides, they don’t require maintenance frequently.