Heat-proof structure of duct oil tank

The utility model discloses a heat insulating structure of a trough-like oil storage tank, which is used for transformers or magnetic-core reactors, and is arranged with an antimagnetic plate made from copper plate or aluminum plate between a winding or a lower magnetic shield and an upper limb plate of the lower section of the trough-like oil storage tank. On the one hand, because the magnetic isolation of the antimagnetic plate facilitates the magnetic resistance between the winding or the lower magnetic shield and the lower section of the trough-like oil storage tank increasing greatly, the leakage flux into the upper limb plate of the trough-like oil storage tank is reduced; on the other hand, due to high conductivity of copper or aluminum, the leakage flux flowing through the copper plate or aluminum plate into the upper limb plate undergoes a strong vortex diamagnetism from the antimagnetic plate, thus preventing the leakage flux flowing into the upper limb plate, reducing loss and increasing reliability despite partial heating. Therefore, common steel plate characterized by lower cost and easy processing is suitable as a lower section of the oil storage tank to greatly reduce raw material cost and processing cost.