A lifter with electro-permanent magnets is provided. It has an external bearing structure closed at the bottom by a plate, provided with a heat shield, and pole pieces secured under the respective poles and protruding from the bottom plate. Each of the electro-permanent magnets has a reversible magnet arranged on top of one of the poles, of a fixed polarization magnet formed by a plurality of blocks placed along the lateral faces of the pole and of a coil arranged around the reversible magnet to cause the reversal of the polarization of the latter by means of an electrical pulse. An airtight air gap between 1 and 4 mm high is formed between each pole piece and the respective pole through the interposition of a plate of thermal insulation material that resists high temperatures provided at each pole with a rectangular window slightly smaller in size than the pole itself, with the top sides of the pole pieces and/or the bottom sides of the poles being provided with peripheral recesses suitable to act as seats for the positioning of the plate.