高场强永磁磁滤器的设计

Design of High Field Intensity Permanent Magnetic Filter

磁滤器是一种用于弱磁性粉体矿物分选的小型磁选机,其磁系是磁滤器的关键部件,针对国内外磁系磁路设计中的问题,研制了一种磁路独特的永磁磁滤器。把不同结构的轴向磁化和径向磁化的多块NdFeB磁体组合实现聚磁,以轴向充磁环形磁体内径构建分选空间,同时获得了较大的分选空间和高磁场强度。设计了多面挤压装配夹具及装配工艺。在直径29.2mm分选空间上测得最高场强可达1.3T;Magnet数值仿真证明磁滤器磁路设计达到了设计要求,对极弱磁性煤系黄铁矿粉体的直接分选实验表明,该磁滤器用于分选弱磁性粉体效果显著。

Magnetic filter is a small magnetic separator which is used for separating weak magnetic mineral powders, and the magnet assembly is a key component of the magnetic filter. On account of the problems of magnetic circuit design of magnet assembly at home and abroad, a permanent magnetic filter with a unique magnetic circuit was developed. The multi-block NdFeB magnets with axial and radial magnetization were combinated to achieve field concentration. Taking advantage of inner cylinder chamber of axially magnetized magnet ring as working space, high magnetic field intensity is obtained under a larger separating space. Meanwhile the multi-dimensional extrusion assembly jig was designed, along with the assembly process. Maximum field strength up to 1.3T in working chamber with 29.2mm in diameter, and numerical simulation of field distribution proves that magnetic circuit design of the magnetic filter meets the design requirements. The direct separating experiment on weak magnetic pyrite in coal showed an effective separating.