Diploma thesis deals with issues of banding magnetic cores of transformer. The main issue of banding is to guarantee enough force, through whole length of tightening strip, which affects on activity of transformer. Core, banded with bigger force in strips, has smaller dynamics response during operation and consequently minor losses. Measurements were done with 0.5, 1.5 and 2.5 wrap of strips, tighten from one side and with 2.5 wrap of strip tighten from both sides. With tightening device we tighten the beginning of strip with demanded force, while we measure the force at the end of strip. That helps us to find out how much tightening force is preserved in strip on certain length. We came to the conclusion that with tightening we lose a lot of force because of friction. Based on measurements with 0.5 wrap of strip we measured that in strip we can preserve 60 % of force guaranteed at the beginning of the strip. When we measuring with 1.5 and 2.5 wrap straps, this value represents only 15% banding force. Process of tightening we improved with tighten from both sides, which carried up to 20 % higher force in strip than tightening from one side.
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