A flange fitted around a round cylindrical condenser core of a bushing is described. The flange comprises an annular lower flange part arranged to fit around a radial shoulder of the condenser core such that a lower shoulder chamfer of the shoulder rests against lower flange chamfer of the lower flange part around the circumference of the condenser core; and an annular upper flange part fastened to the lower flange part and fits around the condenser core above an upper shoulder chamfer of the shoulder. An upper flange chamfer of the upper flange part is between an upper sealing element and a lower sealing element, forming an annular chamfer space is formed between the upper flange chamfer and the upper shoulder chamfer between the upper and lower sealing elements. The flange comprises an injection through hole for a filler material to be injected there through to fill the chamfer space.