Transformer Noise Abatement Using Tuned Sound Enclosure Panels

This report covers work performed by the Allis-Chalmers Corporation (A-C) on transformer noise shells under contract to the Electric Power Research Institute (EPRI). The program is directed at reducing noise emitted from power transformers using a close-fitting, integrally-mounted noise shell technique. The noise shell consists of a series of panels attached to the tank by means of isolators. Sound absorptive materials are not required and reductions in excess of 20 dBA can be achieved by proper design of the panels. The program is divided into two phases 1) Phase 1 for development, and 2) Phase 2 for commercial production design and demonstration. The approach requires no state-of-the-art breakthroughs. However, the concept is considered new and as a result the primary objectives of Phase 1 of the program are to establish if it is practical and economical. The follow-on Phase 2 would take the concepts into full product design. This document reports the work performed under two related contracts, covering a period from October 1, 1975 through September 30, 1978.