By absorbing advanced technologies from both home and abroad, 110kV power transformer usescomputer to conduct precise analysis and computation on the static and dynamic impact gradient inthe power field to determine relatively reasonable structure so that the power field and the impactgradient can be reasonably distributed, minimum in mechanical power and lower partially. S18, S20and S22 series oil tank is a square flat and bell jar structure with fiber container being added insidethe coil and quantity of struts being added to enhance mechanical intensity of intensity, high powerintensity and low dielectric loss constants have enough machine press button and studs and the strapat the end adopts special techniques and materials to drastically improve capacity to resist againstshort circuit in the transformer. Special positioning structure is adopted for the transformer and theoil tank to address the relative displacement of the core and winding assembly and the oil tank. Itcan undertake “3g” impact in transformation. This series of product entirely conforms to demands ofhigh supply quality, low loss of noise and long maintenance interval.