What is a lifting magnet and how does it work? What are the types of magnets used for lifting? To answer the above questions, first, we need to find out and understand what lifting magnets are.
Lifting magnets are what they sound like, magnets that use magnetic force generated to lift objects, referred here as ferrous materials, like steel plates, sheets, coils, ballets, etc.
Basically, there are 3 main types of magnets used for lifting application, in terms of magnet characteristics: permanent lifting magnets, electro lifting magnets, and electro-permanent lifting magnets. Yeah, the latter sounds like a hybrid of the former two magnets.
Magnets are applied in industrial lifting applications due to their magnetic clamping force that attracts steel material or parts. The generation of magnetic force varies for each magnet type.
Permanent lifting magnet – Has a block with the main body and a rotor. It contains 2 magnets in the main body and rotor each. These 2 magnets, when positioned in the same direction, produce magnetic flux that reaches the metallic objects to be lifted.
Electro lifting magnet – Electromagnets are different from permanent magnets. They are made of coils of wire with electricity passing through them. Moving charges create magnetic fields, so when the coils of wire in an electromagnet have an electric current passing through them, the coils behave like a magnet.
Electro-permanent lifting magnet – Composed of 2 magnetic power sources. One is a set of high intrinsic coercive force (Hci) magnets and another is a set of low Hci magnets. The low Hci magnets are wrapped in electrical wire coils. Changing the direction of current pulse in the coils can change the direction of its magnetic orientation. When the 2 sets of the magnets have same magnetic direction, the permanent-electro lifting magnet gains attractive force to ferromagnetic work piece. If with opposite magnetic directions which absorb each other’s energy, no magnetic force existed for clamping.
electric & magnetic fields – magnetic force
Knowing the exact differences of lifting magnets between electro-permanent type, electro type and permanent type, can help us gain a better understanding of their possible applications in industry.