The winding is the circuit part of the transformer, which is wound with a paper-wrapped insulated flat wire or round wire.

O elemento condutor do transformador bobina é feito de fio de cobre com seção retangular e alta condutividade, e a parte externa é envolvida com duas camadas de papel kraft para fins de isolamento. Para almofadas isolantes do mesmo material, o número de fios de cobre depende da tensão de trabalho, de modo que o bobina elements have sufficient insulating strength between layers. Using glue on the outermost layer of insulating paper, each wrapping layer is glued together to form a tight coil. To reduce eddy current losses, line crossings are made at predetermined positions of the conductor elements. The coil of the shell-type transformer is fixed vertically. In order to prevent misalignment, a wooden wedge is inserted between the coil and the iron core. All ends of the coil are fixed by the wire core and the oil tank. The external force is distributed in a large area, which greatly improves the mechanical strength. .