Abstract: A dry-type power transformer has a lower acoustical noise level by inserting sound absorbing pads at predetermined locations in an air gap formed longitudinally between a low voltage coil and its corresponding leg member of the transformer's iron core. The pads function as baffles to lower the acoustical noise caused by magnetostriction and other forces when the transformer is energized. The pads are arranged in alternate patterns between the top and the bottom of the air gap.

Abstract: A magnetic core assembly and method of assembling a magnetic core assembly. The core assembly includes laminated magnetic core tightly clamped together by a pair of unitized flanged clamps. Each unitized flanged clamp has a generally flat surface and a peripheral flange. The generally flat surface defines at least one opening for receiving a coil and a number of holes adjacent the opening for receiving assembly hardware. The core is assembled by placing a first one of the two unitized flanged clamps, flange down on a generally horizontal work surface. Alignment pins are placed in one or more of the assembly hardware apertures adjacent the coil opening. The segments of the first core lamination are slidably placed on the alignment pins such that they lie on the flat surface of the first unitized flange clamp. The segments of each remaining core lamination are slidably placed on the alignment pins until the required number of laminations have been installed.